Thomas Gleixner | 457c899 | 2019-05-19 13:08:55 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | /* |
| 3 | * linux/fs/exec.c |
| 4 | * |
| 5 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 6 | */ |
| 7 | |
| 8 | /* |
| 9 | * #!-checking implemented by tytso. |
| 10 | */ |
| 11 | /* |
| 12 | * Demand-loading implemented 01.12.91 - no need to read anything but |
| 13 | * the header into memory. The inode of the executable is put into |
| 14 | * "current->executable", and page faults do the actual loading. Clean. |
| 15 | * |
| 16 | * Once more I can proudly say that linux stood up to being changed: it |
| 17 | * was less than 2 hours work to get demand-loading completely implemented. |
| 18 | * |
| 19 | * Demand loading changed July 1993 by Eric Youngdale. Use mmap instead, |
| 20 | * current->executable is only used by the procfs. This allows a dispatch |
| 21 | * table to check for several different types of binary formats. We keep |
| 22 | * trying until we recognize the file or we run out of supported binary |
Aleksa Sarai | 613cc2b | 2016-12-21 16:26:24 +1100 | [diff] [blame] | 23 | * formats. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | */ |
| 25 | |
Scott Branden | b89999d0 | 2020-10-02 10:38:15 -0700 | [diff] [blame] | 26 | #include <linux/kernel_read_file.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | #include <linux/slab.h> |
| 28 | #include <linux/file.h> |
Al Viro | 9f3acc3 | 2008-04-24 07:44:08 -0400 | [diff] [blame] | 29 | #include <linux/fdtable.h> |
Hugh Dickins | ba92a43 | 2008-07-25 01:45:43 -0700 | [diff] [blame] | 30 | #include <linux/mm.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 31 | #include <linux/stat.h> |
| 32 | #include <linux/fcntl.h> |
Hugh Dickins | ba92a43 | 2008-07-25 01:45:43 -0700 | [diff] [blame] | 33 | #include <linux/swap.h> |
Neil Horman | 74aadce | 2007-10-16 23:26:35 -0700 | [diff] [blame] | 34 | #include <linux/string.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | #include <linux/init.h> |
Ingo Molnar | 6e84f31 | 2017-02-08 18:51:29 +0100 | [diff] [blame] | 36 | #include <linux/sched/mm.h> |
Ingo Molnar | f7ccbae | 2017-02-08 18:51:30 +0100 | [diff] [blame] | 37 | #include <linux/sched/coredump.h> |
Ingo Molnar | 3f07c01 | 2017-02-08 18:51:30 +0100 | [diff] [blame] | 38 | #include <linux/sched/signal.h> |
Ingo Molnar | 6a3827d | 2017-02-08 18:51:31 +0100 | [diff] [blame] | 39 | #include <linux/sched/numa_balancing.h> |
Ingo Molnar | 2993002 | 2017-02-08 18:51:36 +0100 | [diff] [blame] | 40 | #include <linux/sched/task.h> |
Hugh Dickins | ca5b172 | 2008-07-28 15:46:18 -0700 | [diff] [blame] | 41 | #include <linux/pagemap.h> |
Ingo Molnar | cdd6c48 | 2009-09-21 12:02:48 +0200 | [diff] [blame] | 42 | #include <linux/perf_event.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | #include <linux/highmem.h> |
| 44 | #include <linux/spinlock.h> |
| 45 | #include <linux/key.h> |
| 46 | #include <linux/personality.h> |
| 47 | #include <linux/binfmts.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | #include <linux/utsname.h> |
Sukadev Bhattiprolu | 84d7378 | 2006-12-08 02:38:01 -0800 | [diff] [blame] | 49 | #include <linux/pid_namespace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | #include <linux/module.h> |
| 51 | #include <linux/namei.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | #include <linux/mount.h> |
| 53 | #include <linux/security.h> |
| 54 | #include <linux/syscalls.h> |
Jay Lan | 8f0ab51 | 2006-09-30 23:28:59 -0700 | [diff] [blame] | 55 | #include <linux/tsacct_kern.h> |
Matt Helsley | 9f46080 | 2005-11-07 00:59:16 -0800 | [diff] [blame] | 56 | #include <linux/cn_proc.h> |
Al Viro | 473ae30 | 2006-04-26 14:04:08 -0400 | [diff] [blame] | 57 | #include <linux/audit.h> |
Johannes Berg | 5f4123b | 2008-07-09 10:28:40 +0200 | [diff] [blame] | 58 | #include <linux/kmod.h> |
Eric Paris | 6110e3a | 2008-12-17 13:53:20 -0500 | [diff] [blame] | 59 | #include <linux/fsnotify.h> |
Al Viro | 5ad4e53 | 2009-03-29 19:50:06 -0400 | [diff] [blame] | 60 | #include <linux/fs_struct.h> |
Ying Han | 3d5992d | 2010-10-26 14:21:23 -0700 | [diff] [blame] | 61 | #include <linux/oom.h> |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 62 | #include <linux/compat.h> |
Mimi Zohar | b44a7df | 2015-12-28 16:02:29 -0500 | [diff] [blame] | 63 | #include <linux/vmalloc.h> |
Jens Axboe | 0f21220 | 2020-09-13 13:09:39 -0600 | [diff] [blame] | 64 | #include <linux/io_uring.h> |
Gabriel Krisman Bertazi | 1446e1d | 2020-11-27 14:32:34 -0500 | [diff] [blame] | 65 | #include <linux/syscall_user_dispatch.h> |
Luis Chamberlain | 66ad398 | 2022-01-21 22:13:17 -0800 | [diff] [blame] | 66 | #include <linux/coredump.h> |
Andrei Vagin | 2b5f9da | 2022-09-20 17:31:19 -0700 | [diff] [blame] | 67 | #include <linux/time_namespace.h> |
Beau Belgrave | fd59351 | 2023-03-28 16:52:09 -0700 | [diff] [blame] | 68 | #include <linux/user_events.h> |
Kent Overstreet | 932562a | 2023-12-15 15:58:20 -0500 | [diff] [blame] | 69 | #include <linux/rseq.h> |
Jinjiang Tu | 3a9e567 | 2024-03-28 19:10:08 +0800 | [diff] [blame] | 70 | #include <linux/ksm.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | |
Linus Torvalds | 7c0f6ba | 2016-12-24 11:46:01 -0800 | [diff] [blame] | 72 | #include <linux/uaccess.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | #include <asm/mmu_context.h> |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 74 | #include <asm/tlb.h> |
KAMEZAWA Hiroyuki | 43d2b11 | 2012-01-10 15:08:09 -0800 | [diff] [blame] | 75 | |
| 76 | #include <trace/events/task.h> |
David Howells | a6f76f2 | 2008-11-14 10:39:24 +1100 | [diff] [blame] | 77 | #include "internal.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | |
David Smith | 4ff16c2 | 2012-02-07 10:11:05 -0600 | [diff] [blame] | 79 | #include <trace/events/sched.h> |
| 80 | |
Eric W. Biederman | 56305aa | 2020-05-29 22:00:54 -0500 | [diff] [blame] | 81 | static int bprm_creds_from_file(struct linux_binprm *bprm); |
| 82 | |
Alan Cox | d6e7114 | 2005-06-23 00:09:43 -0700 | [diff] [blame] | 83 | int suid_dumpable = 0; |
| 84 | |
Alexey Dobriyan | e4dc1b1 | 2007-10-16 23:26:03 -0700 | [diff] [blame] | 85 | static LIST_HEAD(formats); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | static DEFINE_RWLOCK(binfmt_lock); |
| 87 | |
Al Viro | 8fc3dc5 | 2012-03-17 03:05:16 -0400 | [diff] [blame] | 88 | void __register_binfmt(struct linux_binfmt * fmt, int insert) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | write_lock(&binfmt_lock); |
Ivan Kokshaysky | 74641f5 | 2009-04-30 15:08:49 -0700 | [diff] [blame] | 91 | insert ? list_add(&fmt->lh, &formats) : |
| 92 | list_add_tail(&fmt->lh, &formats); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | write_unlock(&binfmt_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | } |
| 95 | |
Ivan Kokshaysky | 74641f5 | 2009-04-30 15:08:49 -0700 | [diff] [blame] | 96 | EXPORT_SYMBOL(__register_binfmt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | |
Alexey Dobriyan | f6b450d | 2007-10-16 23:26:04 -0700 | [diff] [blame] | 98 | void unregister_binfmt(struct linux_binfmt * fmt) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 100 | write_lock(&binfmt_lock); |
Alexey Dobriyan | e4dc1b1 | 2007-10-16 23:26:03 -0700 | [diff] [blame] | 101 | list_del(&fmt->lh); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 102 | write_unlock(&binfmt_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 103 | } |
| 104 | |
| 105 | EXPORT_SYMBOL(unregister_binfmt); |
| 106 | |
| 107 | static inline void put_binfmt(struct linux_binfmt * fmt) |
| 108 | { |
| 109 | module_put(fmt->module); |
| 110 | } |
| 111 | |
Eric W. Biederman | 90f8572 | 2015-06-29 14:42:03 -0500 | [diff] [blame] | 112 | bool path_noexec(const struct path *path) |
| 113 | { |
| 114 | return (path->mnt->mnt_flags & MNT_NOEXEC) || |
| 115 | (path->mnt->mnt_sb->s_iflags & SB_I_NOEXEC); |
| 116 | } |
| 117 | |
Josh Triplett | 69369a7 | 2014-04-03 14:48:27 -0700 | [diff] [blame] | 118 | #ifdef CONFIG_USELIB |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | /* |
| 120 | * Note that a shared library must be both readable and executable due to |
| 121 | * security reasons. |
| 122 | * |
Tom Rix | b452722 | 2022-02-11 08:09:40 -0800 | [diff] [blame] | 123 | * Also note that we take the address to load from the file itself. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 124 | */ |
Heiko Carstens | 1e7bfb2 | 2009-01-14 14:14:29 +0100 | [diff] [blame] | 125 | SYSCALL_DEFINE1(uselib, const char __user *, library) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | { |
Al Viro | 72c2d53 | 2013-09-22 16:27:52 -0400 | [diff] [blame] | 127 | struct linux_binfmt *fmt; |
Al Viro | 964bd18 | 2008-07-26 03:33:14 -0400 | [diff] [blame] | 128 | struct file *file; |
Jeff Layton | 91a27b2 | 2012-10-10 15:25:28 -0400 | [diff] [blame] | 129 | struct filename *tmp = getname(library); |
Al Viro | 964bd18 | 2008-07-26 03:33:14 -0400 | [diff] [blame] | 130 | int error = PTR_ERR(tmp); |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 131 | static const struct open_flags uselib_flags = { |
Linus Torvalds | 3eab830 | 2024-01-24 13:12:20 -0800 | [diff] [blame] | 132 | .open_flag = O_LARGEFILE | O_RDONLY, |
Al Viro | 62fb4a1 | 2015-12-26 22:33:24 -0500 | [diff] [blame] | 133 | .acc_mode = MAY_READ | MAY_EXEC, |
Al Viro | f9652e1 | 2013-06-11 08:23:01 +0400 | [diff] [blame] | 134 | .intent = LOOKUP_OPEN, |
| 135 | .lookup_flags = LOOKUP_FOLLOW, |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 136 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | |
Al Viro | 6e8341a | 2009-04-06 11:16:22 -0400 | [diff] [blame] | 138 | if (IS_ERR(tmp)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | goto out; |
| 140 | |
Al Viro | f9652e1 | 2013-06-11 08:23:01 +0400 | [diff] [blame] | 141 | file = do_filp_open(AT_FDCWD, tmp, &uselib_flags); |
Al Viro | 6e8341a | 2009-04-06 11:16:22 -0400 | [diff] [blame] | 142 | putname(tmp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | error = PTR_ERR(file); |
| 144 | if (IS_ERR(file)) |
| 145 | goto out; |
| 146 | |
Kees Cook | 633fb6a | 2020-08-11 18:36:26 -0700 | [diff] [blame] | 147 | /* |
| 148 | * may_open() has already checked for this, so it should be |
| 149 | * impossible to trip now. But we need to be extra cautious |
| 150 | * and check again at the very end too. |
| 151 | */ |
Kees Cook | db19c91 | 2020-08-11 18:36:23 -0700 | [diff] [blame] | 152 | error = -EACCES; |
Kees Cook | 0fd338b | 2020-08-11 18:36:30 -0700 | [diff] [blame] | 153 | if (WARN_ON_ONCE(!S_ISREG(file_inode(file)->i_mode) || |
| 154 | path_noexec(&file->f_path))) |
Al Viro | 6e8341a | 2009-04-06 11:16:22 -0400 | [diff] [blame] | 155 | goto exit; |
| 156 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | error = -ENOEXEC; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | |
Al Viro | 72c2d53 | 2013-09-22 16:27:52 -0400 | [diff] [blame] | 159 | read_lock(&binfmt_lock); |
| 160 | list_for_each_entry(fmt, &formats, lh) { |
| 161 | if (!fmt->load_shlib) |
| 162 | continue; |
| 163 | if (!try_module_get(fmt->module)) |
| 164 | continue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | read_unlock(&binfmt_lock); |
Al Viro | 72c2d53 | 2013-09-22 16:27:52 -0400 | [diff] [blame] | 166 | error = fmt->load_shlib(file); |
| 167 | read_lock(&binfmt_lock); |
| 168 | put_binfmt(fmt); |
| 169 | if (error != -ENOEXEC) |
| 170 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | } |
Al Viro | 72c2d53 | 2013-09-22 16:27:52 -0400 | [diff] [blame] | 172 | read_unlock(&binfmt_lock); |
Al Viro | 6e8341a | 2009-04-06 11:16:22 -0400 | [diff] [blame] | 173 | exit: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | fput(file); |
| 175 | out: |
Kees Cook | 8f6e3f9 | 2022-10-18 00:14:20 -0700 | [diff] [blame] | 176 | return error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 177 | } |
Josh Triplett | 69369a7 | 2014-04-03 14:48:27 -0700 | [diff] [blame] | 178 | #endif /* #ifdef CONFIG_USELIB */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 179 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 180 | #ifdef CONFIG_MMU |
Oleg Nesterov | ae6b585 | 2011-03-06 18:03:11 +0100 | [diff] [blame] | 181 | /* |
| 182 | * The nascent bprm->mm is not visible until exec_mmap() but it can |
| 183 | * use a lot of memory, account these pages in current->mm temporary |
| 184 | * for oom_badness()->get_mm_rss(). Once exec succeeds or fails, we |
| 185 | * change the counter back via acct_arg_size(0). |
| 186 | */ |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 187 | static void acct_arg_size(struct linux_binprm *bprm, unsigned long pages) |
Oleg Nesterov | 3c77f84 | 2010-11-30 20:55:34 +0100 | [diff] [blame] | 188 | { |
| 189 | struct mm_struct *mm = current->mm; |
| 190 | long diff = (long)(pages - bprm->vma_pages); |
| 191 | |
| 192 | if (!mm || !diff) |
| 193 | return; |
| 194 | |
| 195 | bprm->vma_pages = pages; |
Oleg Nesterov | 3c77f84 | 2010-11-30 20:55:34 +0100 | [diff] [blame] | 196 | add_mm_counter(mm, MM_ANONPAGES, diff); |
Oleg Nesterov | 3c77f84 | 2010-11-30 20:55:34 +0100 | [diff] [blame] | 197 | } |
| 198 | |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 199 | static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos, |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 200 | int write) |
| 201 | { |
| 202 | struct page *page; |
Linus Torvalds | f313c51 | 2023-06-19 11:34:15 -0700 | [diff] [blame] | 203 | struct vm_area_struct *vma = bprm->vma; |
| 204 | struct mm_struct *mm = bprm->mm; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 205 | int ret; |
| 206 | |
Linus Torvalds | f313c51 | 2023-06-19 11:34:15 -0700 | [diff] [blame] | 207 | /* |
| 208 | * Avoid relying on expanding the stack down in GUP (which |
| 209 | * does not work for STACK_GROWSUP anyway), and just do it |
| 210 | * by hand ahead of time. |
| 211 | */ |
| 212 | if (write && pos < vma->vm_start) { |
| 213 | mmap_write_lock(mm); |
Linus Torvalds | 8d7071a | 2023-06-24 13:45:51 -0700 | [diff] [blame] | 214 | ret = expand_downwards(vma, pos); |
Linus Torvalds | f313c51 | 2023-06-19 11:34:15 -0700 | [diff] [blame] | 215 | if (unlikely(ret < 0)) { |
| 216 | mmap_write_unlock(mm); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 217 | return NULL; |
Linus Torvalds | f313c51 | 2023-06-19 11:34:15 -0700 | [diff] [blame] | 218 | } |
| 219 | mmap_write_downgrade(mm); |
| 220 | } else |
| 221 | mmap_read_lock(mm); |
Lorenzo Stoakes | 9beae1e | 2016-10-13 01:20:17 +0100 | [diff] [blame] | 222 | |
Dave Hansen | 1e98779 | 2016-02-12 13:01:54 -0800 | [diff] [blame] | 223 | /* |
| 224 | * We are doing an exec(). 'current' is the process |
Linus Torvalds | f313c51 | 2023-06-19 11:34:15 -0700 | [diff] [blame] | 225 | * doing the exec and 'mm' is the new process's mm. |
Dave Hansen | 1e98779 | 2016-02-12 13:01:54 -0800 | [diff] [blame] | 226 | */ |
Linus Torvalds | f313c51 | 2023-06-19 11:34:15 -0700 | [diff] [blame] | 227 | ret = get_user_pages_remote(mm, pos, 1, |
| 228 | write ? FOLL_WRITE : 0, |
Lorenzo Stoakes | ca5e863 | 2023-05-17 20:25:39 +0100 | [diff] [blame] | 229 | &page, NULL); |
Linus Torvalds | f313c51 | 2023-06-19 11:34:15 -0700 | [diff] [blame] | 230 | mmap_read_unlock(mm); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 231 | if (ret <= 0) |
| 232 | return NULL; |
| 233 | |
Oleg Nesterov | 655c16a | 2019-01-03 15:28:11 -0800 | [diff] [blame] | 234 | if (write) |
Linus Torvalds | f313c51 | 2023-06-19 11:34:15 -0700 | [diff] [blame] | 235 | acct_arg_size(bprm, vma_pages(vma)); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 236 | |
| 237 | return page; |
| 238 | } |
| 239 | |
| 240 | static void put_arg_page(struct page *page) |
| 241 | { |
| 242 | put_page(page); |
| 243 | } |
| 244 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 245 | static void free_arg_pages(struct linux_binprm *bprm) |
| 246 | { |
| 247 | } |
| 248 | |
| 249 | static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos, |
| 250 | struct page *page) |
| 251 | { |
| 252 | flush_cache_page(bprm->vma, pos, page_to_pfn(page)); |
| 253 | } |
| 254 | |
| 255 | static int __bprm_mm_init(struct linux_binprm *bprm) |
| 256 | { |
Luiz Fernando N. Capitulino | eaccbfa | 2009-01-06 14:40:44 -0800 | [diff] [blame] | 257 | int err; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 258 | struct vm_area_struct *vma = NULL; |
| 259 | struct mm_struct *mm = bprm->mm; |
| 260 | |
Linus Torvalds | 490fc05 | 2018-07-21 15:24:03 -0700 | [diff] [blame] | 261 | bprm->vma = vma = vm_area_alloc(mm); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 262 | if (!vma) |
Luiz Fernando N. Capitulino | eaccbfa | 2009-01-06 14:40:44 -0800 | [diff] [blame] | 263 | return -ENOMEM; |
Kirill A. Shutemov | bfd40ea | 2018-07-26 16:37:35 -0700 | [diff] [blame] | 264 | vma_set_anonymous(vma); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 265 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 266 | if (mmap_write_lock_killable(mm)) { |
Michal Hocko | f268dfe | 2016-05-23 16:26:02 -0700 | [diff] [blame] | 267 | err = -EINTR; |
| 268 | goto err_free; |
| 269 | } |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 270 | |
| 271 | /* |
Jinjiang Tu | 3a9e567 | 2024-03-28 19:10:08 +0800 | [diff] [blame] | 272 | * Need to be called with mmap write lock |
| 273 | * held, to avoid race with ksmd. |
| 274 | */ |
| 275 | err = ksm_execve(mm); |
| 276 | if (err) |
| 277 | goto err_ksm; |
| 278 | |
| 279 | /* |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 280 | * Place the stack at the largest stack address the architecture |
| 281 | * supports. Later, we'll move this to an appropriate place. We don't |
| 282 | * use STACK_TOP because that can depend on attributes which aren't |
| 283 | * configured yet. |
| 284 | */ |
Michal Hocko | aacb3d1 | 2011-07-26 16:08:40 -0700 | [diff] [blame] | 285 | BUILD_BUG_ON(VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 286 | vma->vm_end = STACK_TOP_MAX; |
| 287 | vma->vm_start = vma->vm_end - PAGE_SIZE; |
Suren Baghdasaryan | 1c71222 | 2023-01-26 11:37:49 -0800 | [diff] [blame] | 288 | vm_flags_init(vma, VM_SOFTDIRTY | VM_STACK_FLAGS | VM_STACK_INCOMPLETE_SETUP); |
Coly Li | 3ed75eb | 2007-10-18 23:39:15 -0700 | [diff] [blame] | 289 | vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); |
Tavis Ormandy | 462e635e | 2010-12-09 15:29:42 +0100 | [diff] [blame] | 290 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 291 | err = insert_vm_struct(mm, vma); |
Luiz Fernando N. Capitulino | eaccbfa | 2009-01-06 14:40:44 -0800 | [diff] [blame] | 292 | if (err) |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 293 | goto err; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 294 | |
| 295 | mm->stack_vm = mm->total_vm = 1; |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 296 | mmap_write_unlock(mm); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 297 | bprm->p = vma->vm_end - sizeof(void *); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 298 | return 0; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 299 | err: |
Jinjiang Tu | 3a9e567 | 2024-03-28 19:10:08 +0800 | [diff] [blame] | 300 | ksm_exit(mm); |
| 301 | err_ksm: |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 302 | mmap_write_unlock(mm); |
Michal Hocko | f268dfe | 2016-05-23 16:26:02 -0700 | [diff] [blame] | 303 | err_free: |
Luiz Fernando N. Capitulino | eaccbfa | 2009-01-06 14:40:44 -0800 | [diff] [blame] | 304 | bprm->vma = NULL; |
Linus Torvalds | 3928d4f | 2018-07-21 13:48:51 -0700 | [diff] [blame] | 305 | vm_area_free(vma); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 306 | return err; |
| 307 | } |
| 308 | |
| 309 | static bool valid_arg_len(struct linux_binprm *bprm, long len) |
| 310 | { |
| 311 | return len <= MAX_ARG_STRLEN; |
| 312 | } |
| 313 | |
| 314 | #else |
| 315 | |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 316 | static inline void acct_arg_size(struct linux_binprm *bprm, unsigned long pages) |
Oleg Nesterov | 3c77f84 | 2010-11-30 20:55:34 +0100 | [diff] [blame] | 317 | { |
| 318 | } |
| 319 | |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 320 | static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos, |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 321 | int write) |
| 322 | { |
| 323 | struct page *page; |
| 324 | |
| 325 | page = bprm->page[pos / PAGE_SIZE]; |
| 326 | if (!page && write) { |
| 327 | page = alloc_page(GFP_HIGHUSER|__GFP_ZERO); |
| 328 | if (!page) |
| 329 | return NULL; |
| 330 | bprm->page[pos / PAGE_SIZE] = page; |
| 331 | } |
| 332 | |
| 333 | return page; |
| 334 | } |
| 335 | |
| 336 | static void put_arg_page(struct page *page) |
| 337 | { |
| 338 | } |
| 339 | |
| 340 | static void free_arg_page(struct linux_binprm *bprm, int i) |
| 341 | { |
| 342 | if (bprm->page[i]) { |
| 343 | __free_page(bprm->page[i]); |
| 344 | bprm->page[i] = NULL; |
| 345 | } |
| 346 | } |
| 347 | |
| 348 | static void free_arg_pages(struct linux_binprm *bprm) |
| 349 | { |
| 350 | int i; |
| 351 | |
| 352 | for (i = 0; i < MAX_ARG_PAGES; i++) |
| 353 | free_arg_page(bprm, i); |
| 354 | } |
| 355 | |
| 356 | static void flush_arg_page(struct linux_binprm *bprm, unsigned long pos, |
| 357 | struct page *page) |
| 358 | { |
| 359 | } |
| 360 | |
| 361 | static int __bprm_mm_init(struct linux_binprm *bprm) |
| 362 | { |
| 363 | bprm->p = PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *); |
| 364 | return 0; |
| 365 | } |
| 366 | |
| 367 | static bool valid_arg_len(struct linux_binprm *bprm, long len) |
| 368 | { |
| 369 | return len <= bprm->p; |
| 370 | } |
| 371 | |
| 372 | #endif /* CONFIG_MMU */ |
| 373 | |
| 374 | /* |
| 375 | * Create a new mm_struct and populate it with a temporary stack |
| 376 | * vm_area_struct. We don't have enough context at this point to set the stack |
| 377 | * flags, permissions, and offset, so we use temporary values. We'll update |
| 378 | * them later in setup_arg_pages(). |
| 379 | */ |
Yuanhan Liu | 9cc64ce | 2013-02-20 13:16:01 +1100 | [diff] [blame] | 380 | static int bprm_mm_init(struct linux_binprm *bprm) |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 381 | { |
| 382 | int err; |
| 383 | struct mm_struct *mm = NULL; |
| 384 | |
| 385 | bprm->mm = mm = mm_alloc(); |
| 386 | err = -ENOMEM; |
| 387 | if (!mm) |
| 388 | goto err; |
| 389 | |
Kees Cook | c31dbb14 | 2018-04-10 16:35:01 -0700 | [diff] [blame] | 390 | /* Save current stack limit for all calculations made during exec. */ |
| 391 | task_lock(current->group_leader); |
| 392 | bprm->rlim_stack = current->signal->rlim[RLIMIT_STACK]; |
| 393 | task_unlock(current->group_leader); |
| 394 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 395 | err = __bprm_mm_init(bprm); |
| 396 | if (err) |
| 397 | goto err; |
| 398 | |
| 399 | return 0; |
| 400 | |
| 401 | err: |
| 402 | if (mm) { |
| 403 | bprm->mm = NULL; |
| 404 | mmdrop(mm); |
| 405 | } |
| 406 | |
| 407 | return err; |
| 408 | } |
| 409 | |
Oleg Nesterov | ba2d0162 | 2011-03-06 18:02:37 +0100 | [diff] [blame] | 410 | struct user_arg_ptr { |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 411 | #ifdef CONFIG_COMPAT |
| 412 | bool is_compat; |
| 413 | #endif |
| 414 | union { |
| 415 | const char __user *const __user *native; |
| 416 | #ifdef CONFIG_COMPAT |
Al Viro | 38b983b | 2012-09-30 13:38:55 -0400 | [diff] [blame] | 417 | const compat_uptr_t __user *compat; |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 418 | #endif |
| 419 | } ptr; |
Oleg Nesterov | ba2d0162 | 2011-03-06 18:02:37 +0100 | [diff] [blame] | 420 | }; |
| 421 | |
| 422 | static const char __user *get_user_arg_ptr(struct user_arg_ptr argv, int nr) |
Oleg Nesterov | 1d1dbf8 | 2011-03-06 18:02:21 +0100 | [diff] [blame] | 423 | { |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 424 | const char __user *native; |
Oleg Nesterov | 1d1dbf8 | 2011-03-06 18:02:21 +0100 | [diff] [blame] | 425 | |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 426 | #ifdef CONFIG_COMPAT |
| 427 | if (unlikely(argv.is_compat)) { |
| 428 | compat_uptr_t compat; |
| 429 | |
| 430 | if (get_user(compat, argv.ptr.compat + nr)) |
| 431 | return ERR_PTR(-EFAULT); |
| 432 | |
| 433 | return compat_ptr(compat); |
| 434 | } |
| 435 | #endif |
| 436 | |
| 437 | if (get_user(native, argv.ptr.native + nr)) |
Oleg Nesterov | 1d1dbf8 | 2011-03-06 18:02:21 +0100 | [diff] [blame] | 438 | return ERR_PTR(-EFAULT); |
| 439 | |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 440 | return native; |
Oleg Nesterov | 1d1dbf8 | 2011-03-06 18:02:21 +0100 | [diff] [blame] | 441 | } |
| 442 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 443 | /* |
| 444 | * count() counts the number of strings in array ARGV. |
| 445 | */ |
Oleg Nesterov | ba2d0162 | 2011-03-06 18:02:37 +0100 | [diff] [blame] | 446 | static int count(struct user_arg_ptr argv, int max) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 447 | { |
| 448 | int i = 0; |
| 449 | |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 450 | if (argv.ptr.native != NULL) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 451 | for (;;) { |
Oleg Nesterov | 1d1dbf8 | 2011-03-06 18:02:21 +0100 | [diff] [blame] | 452 | const char __user *p = get_user_arg_ptr(argv, i); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 453 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | if (!p) |
| 455 | break; |
Oleg Nesterov | 1d1dbf8 | 2011-03-06 18:02:21 +0100 | [diff] [blame] | 456 | |
| 457 | if (IS_ERR(p)) |
| 458 | return -EFAULT; |
| 459 | |
Xi Wang | 6d92d4f | 2013-01-11 14:31:48 -0800 | [diff] [blame] | 460 | if (i >= max) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 461 | return -E2BIG; |
Xi Wang | 6d92d4f | 2013-01-11 14:31:48 -0800 | [diff] [blame] | 462 | ++i; |
Roland McGrath | 9aea5a6 | 2010-09-07 19:37:06 -0700 | [diff] [blame] | 463 | |
| 464 | if (fatal_signal_pending(current)) |
| 465 | return -ERESTARTNOHAND; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | cond_resched(); |
| 467 | } |
| 468 | } |
| 469 | return i; |
| 470 | } |
| 471 | |
Eric W. Biederman | be619f7 | 2020-07-13 12:06:48 -0500 | [diff] [blame] | 472 | static int count_strings_kernel(const char *const *argv) |
| 473 | { |
| 474 | int i; |
| 475 | |
| 476 | if (!argv) |
| 477 | return 0; |
| 478 | |
| 479 | for (i = 0; argv[i]; ++i) { |
| 480 | if (i >= MAX_ARG_STRINGS) |
| 481 | return -E2BIG; |
| 482 | if (fatal_signal_pending(current)) |
| 483 | return -ERESTARTNOHAND; |
| 484 | cond_resched(); |
| 485 | } |
| 486 | return i; |
| 487 | } |
| 488 | |
Kees Cook | 084ebf7 | 2024-06-21 13:50:43 -0700 | [diff] [blame] | 489 | static inline int bprm_set_stack_limit(struct linux_binprm *bprm, |
| 490 | unsigned long limit) |
| 491 | { |
| 492 | #ifdef CONFIG_MMU |
Kees Cook | 21f9310 | 2024-06-21 13:50:44 -0700 | [diff] [blame] | 493 | /* Avoid a pathological bprm->p. */ |
| 494 | if (bprm->p < limit) |
| 495 | return -E2BIG; |
Kees Cook | 084ebf7 | 2024-06-21 13:50:43 -0700 | [diff] [blame] | 496 | bprm->argmin = bprm->p - limit; |
| 497 | #endif |
| 498 | return 0; |
| 499 | } |
| 500 | static inline bool bprm_hit_stack_limit(struct linux_binprm *bprm) |
| 501 | { |
| 502 | #ifdef CONFIG_MMU |
| 503 | return bprm->p < bprm->argmin; |
| 504 | #else |
| 505 | return false; |
| 506 | #endif |
| 507 | } |
| 508 | |
Kees Cook | 60371f4 | 2024-05-19 17:17:59 -0700 | [diff] [blame] | 509 | /* |
| 510 | * Calculate bprm->argmin from: |
| 511 | * - _STK_LIM |
| 512 | * - ARG_MAX |
| 513 | * - bprm->rlim_stack.rlim_cur |
| 514 | * - bprm->argc |
| 515 | * - bprm->envc |
| 516 | * - bprm->p |
| 517 | */ |
Eric W. Biederman | d8b9cd5 | 2020-07-12 08:23:54 -0500 | [diff] [blame] | 518 | static int bprm_stack_limits(struct linux_binprm *bprm) |
Oleg Nesterov | 655c16a | 2019-01-03 15:28:11 -0800 | [diff] [blame] | 519 | { |
| 520 | unsigned long limit, ptr_size; |
| 521 | |
Oleg Nesterov | 655c16a | 2019-01-03 15:28:11 -0800 | [diff] [blame] | 522 | /* |
| 523 | * Limit to 1/4 of the max stack size or 3/4 of _STK_LIM |
| 524 | * (whichever is smaller) for the argv+env strings. |
| 525 | * This ensures that: |
| 526 | * - the remaining binfmt code will not run out of stack space, |
| 527 | * - the program will have a reasonable amount of stack left |
| 528 | * to work from. |
| 529 | */ |
| 530 | limit = _STK_LIM / 4 * 3; |
| 531 | limit = min(limit, bprm->rlim_stack.rlim_cur / 4); |
| 532 | /* |
| 533 | * We've historically supported up to 32 pages (ARG_MAX) |
| 534 | * of argument strings even with small stacks |
| 535 | */ |
| 536 | limit = max_t(unsigned long, limit, ARG_MAX); |
Kees Cook | 21f9310 | 2024-06-21 13:50:44 -0700 | [diff] [blame] | 537 | /* Reject totally pathological counts. */ |
| 538 | if (bprm->argc < 0 || bprm->envc < 0) |
| 539 | return -E2BIG; |
Oleg Nesterov | 655c16a | 2019-01-03 15:28:11 -0800 | [diff] [blame] | 540 | /* |
| 541 | * We must account for the size of all the argv and envp pointers to |
| 542 | * the argv and envp strings, since they will also take up space in |
| 543 | * the stack. They aren't stored until much later when we can't |
| 544 | * signal to the parent that the child has run out of stack space. |
| 545 | * Instead, calculate it here so it's possible to fail gracefully. |
Kees Cook | dcd46d8 | 2022-01-31 16:09:47 -0800 | [diff] [blame] | 546 | * |
| 547 | * In the case of argc = 0, make sure there is space for adding a |
| 548 | * empty string (which will bump argc to 1), to ensure confused |
| 549 | * userspace programs don't start processing from argv[1], thinking |
| 550 | * argc can never be 0, to keep them from walking envp by accident. |
| 551 | * See do_execveat_common(). |
Oleg Nesterov | 655c16a | 2019-01-03 15:28:11 -0800 | [diff] [blame] | 552 | */ |
Kees Cook | 21f9310 | 2024-06-21 13:50:44 -0700 | [diff] [blame] | 553 | if (check_add_overflow(max(bprm->argc, 1), bprm->envc, &ptr_size) || |
| 554 | check_mul_overflow(ptr_size, sizeof(void *), &ptr_size)) |
| 555 | return -E2BIG; |
Oleg Nesterov | 655c16a | 2019-01-03 15:28:11 -0800 | [diff] [blame] | 556 | if (limit <= ptr_size) |
| 557 | return -E2BIG; |
| 558 | limit -= ptr_size; |
| 559 | |
Kees Cook | 084ebf7 | 2024-06-21 13:50:43 -0700 | [diff] [blame] | 560 | return bprm_set_stack_limit(bprm, limit); |
Oleg Nesterov | 655c16a | 2019-01-03 15:28:11 -0800 | [diff] [blame] | 561 | } |
| 562 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 563 | /* |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 564 | * 'copy_strings()' copies argument/environment strings from the old |
| 565 | * processes's memory to the new process's stack. The call to get_user_pages() |
| 566 | * ensures the destination page is created and not swapped out. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | */ |
Oleg Nesterov | ba2d0162 | 2011-03-06 18:02:37 +0100 | [diff] [blame] | 568 | static int copy_strings(int argc, struct user_arg_ptr argv, |
Adrian Bunk | 75c96f8 | 2005-05-05 16:16:09 -0700 | [diff] [blame] | 569 | struct linux_binprm *bprm) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 570 | { |
| 571 | struct page *kmapped_page = NULL; |
| 572 | char *kaddr = NULL; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 573 | unsigned long kpos = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 574 | int ret; |
| 575 | |
| 576 | while (argc-- > 0) { |
David Howells | d762746 | 2010-08-17 23:52:56 +0100 | [diff] [blame] | 577 | const char __user *str; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 578 | int len; |
| 579 | unsigned long pos; |
| 580 | |
Oleg Nesterov | 1d1dbf8 | 2011-03-06 18:02:21 +0100 | [diff] [blame] | 581 | ret = -EFAULT; |
| 582 | str = get_user_arg_ptr(argv, argc); |
| 583 | if (IS_ERR(str)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 584 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 585 | |
Oleg Nesterov | 1d1dbf8 | 2011-03-06 18:02:21 +0100 | [diff] [blame] | 586 | len = strnlen_user(str, MAX_ARG_STRLEN); |
| 587 | if (!len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 588 | goto out; |
Oleg Nesterov | 1d1dbf8 | 2011-03-06 18:02:21 +0100 | [diff] [blame] | 589 | |
| 590 | ret = -E2BIG; |
| 591 | if (!valid_arg_len(bprm, len)) |
| 592 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 593 | |
Tom Rix | b452722 | 2022-02-11 08:09:40 -0800 | [diff] [blame] | 594 | /* We're going to work our way backwards. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 595 | pos = bprm->p; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 596 | str += len; |
| 597 | bprm->p -= len; |
Kees Cook | 084ebf7 | 2024-06-21 13:50:43 -0700 | [diff] [blame] | 598 | if (bprm_hit_stack_limit(bprm)) |
Oleg Nesterov | 655c16a | 2019-01-03 15:28:11 -0800 | [diff] [blame] | 599 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 600 | |
| 601 | while (len > 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 602 | int offset, bytes_to_copy; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 603 | |
Roland McGrath | 9aea5a6 | 2010-09-07 19:37:06 -0700 | [diff] [blame] | 604 | if (fatal_signal_pending(current)) { |
| 605 | ret = -ERESTARTNOHAND; |
| 606 | goto out; |
| 607 | } |
Roland McGrath | 7993bc1 | 2010-09-07 19:36:28 -0700 | [diff] [blame] | 608 | cond_resched(); |
| 609 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 610 | offset = pos % PAGE_SIZE; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 611 | if (offset == 0) |
| 612 | offset = PAGE_SIZE; |
| 613 | |
| 614 | bytes_to_copy = offset; |
| 615 | if (bytes_to_copy > len) |
| 616 | bytes_to_copy = len; |
| 617 | |
| 618 | offset -= bytes_to_copy; |
| 619 | pos -= bytes_to_copy; |
| 620 | str -= bytes_to_copy; |
| 621 | len -= bytes_to_copy; |
| 622 | |
| 623 | if (!kmapped_page || kpos != (pos & PAGE_MASK)) { |
| 624 | struct page *page; |
| 625 | |
| 626 | page = get_arg_page(bprm, pos, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 627 | if (!page) { |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 628 | ret = -E2BIG; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 629 | goto out; |
| 630 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 631 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 632 | if (kmapped_page) { |
Christoph Hellwig | f358afc | 2021-09-02 14:56:36 -0700 | [diff] [blame] | 633 | flush_dcache_page(kmapped_page); |
Fabio M. De Francesco | 3a608cf | 2022-08-03 20:28:56 +0200 | [diff] [blame] | 634 | kunmap_local(kaddr); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 635 | put_arg_page(kmapped_page); |
| 636 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 637 | kmapped_page = page; |
Fabio M. De Francesco | 3a608cf | 2022-08-03 20:28:56 +0200 | [diff] [blame] | 638 | kaddr = kmap_local_page(kmapped_page); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 639 | kpos = pos & PAGE_MASK; |
| 640 | flush_arg_page(bprm, kpos, kmapped_page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 641 | } |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 642 | if (copy_from_user(kaddr+offset, str, bytes_to_copy)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 643 | ret = -EFAULT; |
| 644 | goto out; |
| 645 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 646 | } |
| 647 | } |
| 648 | ret = 0; |
| 649 | out: |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 650 | if (kmapped_page) { |
Christoph Hellwig | f358afc | 2021-09-02 14:56:36 -0700 | [diff] [blame] | 651 | flush_dcache_page(kmapped_page); |
Fabio M. De Francesco | 3a608cf | 2022-08-03 20:28:56 +0200 | [diff] [blame] | 652 | kunmap_local(kaddr); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 653 | put_arg_page(kmapped_page); |
| 654 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | return ret; |
| 656 | } |
| 657 | |
| 658 | /* |
Christoph Hellwig | 986db2d | 2020-06-04 16:51:14 -0700 | [diff] [blame] | 659 | * Copy and argument/environment string from the kernel to the processes stack. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 660 | */ |
Christoph Hellwig | 986db2d | 2020-06-04 16:51:14 -0700 | [diff] [blame] | 661 | int copy_string_kernel(const char *arg, struct linux_binprm *bprm) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 662 | { |
Christoph Hellwig | 762a3af | 2020-06-04 16:51:18 -0700 | [diff] [blame] | 663 | int len = strnlen(arg, MAX_ARG_STRLEN) + 1 /* terminating NUL */; |
| 664 | unsigned long pos = bprm->p; |
Oleg Nesterov | ba2d0162 | 2011-03-06 18:02:37 +0100 | [diff] [blame] | 665 | |
Christoph Hellwig | 762a3af | 2020-06-04 16:51:18 -0700 | [diff] [blame] | 666 | if (len == 0) |
| 667 | return -EFAULT; |
| 668 | if (!valid_arg_len(bprm, len)) |
| 669 | return -E2BIG; |
Oleg Nesterov | ba2d0162 | 2011-03-06 18:02:37 +0100 | [diff] [blame] | 670 | |
Christoph Hellwig | 762a3af | 2020-06-04 16:51:18 -0700 | [diff] [blame] | 671 | /* We're going to work our way backwards. */ |
| 672 | arg += len; |
| 673 | bprm->p -= len; |
Kees Cook | 084ebf7 | 2024-06-21 13:50:43 -0700 | [diff] [blame] | 674 | if (bprm_hit_stack_limit(bprm)) |
Christoph Hellwig | 762a3af | 2020-06-04 16:51:18 -0700 | [diff] [blame] | 675 | return -E2BIG; |
| 676 | |
| 677 | while (len > 0) { |
| 678 | unsigned int bytes_to_copy = min_t(unsigned int, len, |
| 679 | min_not_zero(offset_in_page(pos), PAGE_SIZE)); |
| 680 | struct page *page; |
Christoph Hellwig | 762a3af | 2020-06-04 16:51:18 -0700 | [diff] [blame] | 681 | |
| 682 | pos -= bytes_to_copy; |
| 683 | arg -= bytes_to_copy; |
| 684 | len -= bytes_to_copy; |
| 685 | |
| 686 | page = get_arg_page(bprm, pos, 1); |
| 687 | if (!page) |
| 688 | return -E2BIG; |
Christoph Hellwig | 762a3af | 2020-06-04 16:51:18 -0700 | [diff] [blame] | 689 | flush_arg_page(bprm, pos & PAGE_MASK, page); |
Fabio M. De Francesco | c6e8e36 | 2022-07-24 23:25:23 +0200 | [diff] [blame] | 690 | memcpy_to_page(page, offset_in_page(pos), arg, bytes_to_copy); |
Christoph Hellwig | 762a3af | 2020-06-04 16:51:18 -0700 | [diff] [blame] | 691 | put_arg_page(page); |
| 692 | } |
| 693 | |
| 694 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 695 | } |
Christoph Hellwig | 986db2d | 2020-06-04 16:51:14 -0700 | [diff] [blame] | 696 | EXPORT_SYMBOL(copy_string_kernel); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 697 | |
Eric W. Biederman | be619f7 | 2020-07-13 12:06:48 -0500 | [diff] [blame] | 698 | static int copy_strings_kernel(int argc, const char *const *argv, |
| 699 | struct linux_binprm *bprm) |
| 700 | { |
| 701 | while (argc-- > 0) { |
| 702 | int ret = copy_string_kernel(argv[argc], bprm); |
| 703 | if (ret < 0) |
| 704 | return ret; |
| 705 | if (fatal_signal_pending(current)) |
| 706 | return -ERESTARTNOHAND; |
| 707 | cond_resched(); |
| 708 | } |
| 709 | return 0; |
| 710 | } |
| 711 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 712 | #ifdef CONFIG_MMU |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 713 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 714 | /* |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 715 | * During bprm_mm_init(), we create a temporary stack at STACK_TOP_MAX. Once |
| 716 | * the binfmt code determines where the new stack should reside, we shift it to |
| 717 | * its final location. The process proceeds as follows: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 718 | * |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 719 | * 1) Use shift to calculate the new vma endpoints. |
| 720 | * 2) Extend vma to cover both the old and new ranges. This ensures the |
| 721 | * arguments passed to subsequent functions are consistent. |
| 722 | * 3) Move vma's page tables to the new range. |
| 723 | * 4) Free up any cleared pgd range. |
| 724 | * 5) Shrink the vma to cover only the new range. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 725 | */ |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 726 | static int shift_arg_pages(struct vm_area_struct *vma, unsigned long shift) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 727 | { |
| 728 | struct mm_struct *mm = vma->vm_mm; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 729 | unsigned long old_start = vma->vm_start; |
| 730 | unsigned long old_end = vma->vm_end; |
| 731 | unsigned long length = old_end - old_start; |
| 732 | unsigned long new_start = old_start - shift; |
| 733 | unsigned long new_end = old_end - shift; |
Matthew Wilcox (Oracle) | 19066e5 | 2022-09-06 19:48:56 +0000 | [diff] [blame] | 734 | VMA_ITERATOR(vmi, mm, new_start); |
| 735 | struct vm_area_struct *next; |
Peter Zijlstra | d16dfc5 | 2011-05-24 17:11:45 -0700 | [diff] [blame] | 736 | struct mmu_gather tlb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 737 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 738 | BUG_ON(new_start > new_end); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 739 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 740 | /* |
| 741 | * ensure there are no vmas between where we want to go |
| 742 | * and where we are |
| 743 | */ |
Matthew Wilcox (Oracle) | 19066e5 | 2022-09-06 19:48:56 +0000 | [diff] [blame] | 744 | if (vma != vma_next(&vmi)) |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 745 | return -EFAULT; |
| 746 | |
Liam R. Howlett | b5df092 | 2023-07-24 14:31:52 -0400 | [diff] [blame] | 747 | vma_iter_prev_range(&vmi); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 748 | /* |
| 749 | * cover the whole range: [new_start, old_end) |
| 750 | */ |
Liam R. Howlett | cf51e86 | 2023-01-20 11:26:46 -0500 | [diff] [blame] | 751 | if (vma_expand(&vmi, vma, new_start, old_end, vma->vm_pgoff, NULL)) |
Rik van Riel | 5beb493 | 2010-03-05 13:42:07 -0800 | [diff] [blame] | 752 | return -ENOMEM; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 753 | |
| 754 | /* |
| 755 | * move the page tables downwards, on failure we rely on |
| 756 | * process cleanup to remove whatever mess we made. |
| 757 | */ |
| 758 | if (length != move_page_tables(vma, old_start, |
Joel Fernandes (Google) | b1e5a3d | 2023-09-03 15:13:23 +0000 | [diff] [blame] | 759 | vma, new_start, length, false, true)) |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 760 | return -ENOMEM; |
| 761 | |
| 762 | lru_add_drain(); |
Will Deacon | a72afd8 | 2021-01-27 23:53:45 +0000 | [diff] [blame] | 763 | tlb_gather_mmu(&tlb, mm); |
Matthew Wilcox (Oracle) | 19066e5 | 2022-09-06 19:48:56 +0000 | [diff] [blame] | 764 | next = vma_next(&vmi); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 765 | if (new_end > old_start) { |
| 766 | /* |
| 767 | * when the old and new regions overlap clear from new_end. |
| 768 | */ |
Peter Zijlstra | d16dfc5 | 2011-05-24 17:11:45 -0700 | [diff] [blame] | 769 | free_pgd_range(&tlb, new_end, old_end, new_end, |
Matthew Wilcox (Oracle) | 19066e5 | 2022-09-06 19:48:56 +0000 | [diff] [blame] | 770 | next ? next->vm_start : USER_PGTABLES_CEILING); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 771 | } else { |
| 772 | /* |
| 773 | * otherwise, clean from old_start; this is done to not touch |
| 774 | * the address space in [new_end, old_start) some architectures |
| 775 | * have constraints on va-space that make this illegal (IA64) - |
| 776 | * for the others its just a little faster. |
| 777 | */ |
Peter Zijlstra | d16dfc5 | 2011-05-24 17:11:45 -0700 | [diff] [blame] | 778 | free_pgd_range(&tlb, old_start, old_end, new_end, |
Matthew Wilcox (Oracle) | 19066e5 | 2022-09-06 19:48:56 +0000 | [diff] [blame] | 779 | next ? next->vm_start : USER_PGTABLES_CEILING); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 780 | } |
Will Deacon | ae8eba8 | 2021-01-27 23:53:43 +0000 | [diff] [blame] | 781 | tlb_finish_mmu(&tlb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 782 | |
Liam R. Howlett | b373037 | 2023-01-20 11:26:37 -0500 | [diff] [blame] | 783 | vma_prev(&vmi); |
| 784 | /* Shrink the vma to just the new range */ |
Liam R. Howlett | cf51e86 | 2023-01-20 11:26:46 -0500 | [diff] [blame] | 785 | return vma_shrink(&vmi, vma, new_start, new_end, vma->vm_pgoff); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 786 | } |
| 787 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 788 | /* |
| 789 | * Finalizes the stack vm_area_struct. The flags and permissions are updated, |
| 790 | * the stack is optionally relocated, and some extra space is added. |
| 791 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 792 | int setup_arg_pages(struct linux_binprm *bprm, |
| 793 | unsigned long stack_top, |
| 794 | int executable_stack) |
| 795 | { |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 796 | unsigned long ret; |
| 797 | unsigned long stack_shift; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 798 | struct mm_struct *mm = current->mm; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 799 | struct vm_area_struct *vma = bprm->vma; |
| 800 | struct vm_area_struct *prev = NULL; |
| 801 | unsigned long vm_flags; |
| 802 | unsigned long stack_base; |
Michael Neuling | 803bf5e | 2010-02-10 13:56:42 -0800 | [diff] [blame] | 803 | unsigned long stack_size; |
| 804 | unsigned long stack_expand; |
| 805 | unsigned long rlim_stack; |
Nadav Amit | 4a18419 | 2022-05-09 18:20:50 -0700 | [diff] [blame] | 806 | struct mmu_gather tlb; |
Liam R. Howlett | 2286a69 | 2023-01-20 11:26:18 -0500 | [diff] [blame] | 807 | struct vma_iterator vmi; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 808 | |
| 809 | #ifdef CONFIG_STACK_GROWSUP |
James Hogan | d71f290 | 2014-05-13 23:58:24 +0100 | [diff] [blame] | 810 | /* Limit stack size */ |
Kees Cook | c31dbb14 | 2018-04-10 16:35:01 -0700 | [diff] [blame] | 811 | stack_base = bprm->rlim_stack.rlim_max; |
Helge Deller | 22ee3ea | 2020-11-06 19:41:36 +0100 | [diff] [blame] | 812 | |
| 813 | stack_base = calc_max_stack_size(stack_base); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 814 | |
Helge Deller | d045c77 | 2015-05-11 22:01:27 +0200 | [diff] [blame] | 815 | /* Add space for stack randomization. */ |
| 816 | stack_base += (STACK_RND_MASK << PAGE_SHIFT); |
| 817 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 818 | /* Make sure we didn't let the argument array grow too large. */ |
| 819 | if (vma->vm_end - vma->vm_start > stack_base) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 820 | return -ENOMEM; |
| 821 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 822 | stack_base = PAGE_ALIGN(stack_top - stack_base); |
| 823 | |
| 824 | stack_shift = vma->vm_start - stack_base; |
| 825 | mm->arg_start = bprm->p - stack_shift; |
| 826 | bprm->p = vma->vm_end - stack_shift; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 827 | #else |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 828 | stack_top = arch_align_stack(stack_top); |
| 829 | stack_top = PAGE_ALIGN(stack_top); |
Roland McGrath | 1b52818 | 2010-09-07 19:35:49 -0700 | [diff] [blame] | 830 | |
| 831 | if (unlikely(stack_top < mmap_min_addr) || |
| 832 | unlikely(vma->vm_end - vma->vm_start >= stack_top - mmap_min_addr)) |
| 833 | return -ENOMEM; |
| 834 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 835 | stack_shift = vma->vm_end - stack_top; |
| 836 | |
| 837 | bprm->p -= stack_shift; |
| 838 | mm->arg_start = bprm->p; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 839 | #endif |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 840 | |
| 841 | if (bprm->loader) |
| 842 | bprm->loader -= stack_shift; |
| 843 | bprm->exec -= stack_shift; |
| 844 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 845 | if (mmap_write_lock_killable(mm)) |
Michal Hocko | f268dfe | 2016-05-23 16:26:02 -0700 | [diff] [blame] | 846 | return -EINTR; |
| 847 | |
Hugh Dickins | 96a8e13 | 2008-07-10 21:19:20 +0100 | [diff] [blame] | 848 | vm_flags = VM_STACK_FLAGS; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 849 | |
| 850 | /* |
| 851 | * Adjust stack execute permissions; explicitly enable for |
| 852 | * EXSTACK_ENABLE_X, disable for EXSTACK_DISABLE_X and leave alone |
| 853 | * (arch default) otherwise. |
| 854 | */ |
| 855 | if (unlikely(executable_stack == EXSTACK_ENABLE_X)) |
| 856 | vm_flags |= VM_EXEC; |
| 857 | else if (executable_stack == EXSTACK_DISABLE_X) |
| 858 | vm_flags &= ~VM_EXEC; |
| 859 | vm_flags |= mm->def_flags; |
Mel Gorman | a8bef8ff | 2010-05-24 14:32:24 -0700 | [diff] [blame] | 860 | vm_flags |= VM_STACK_INCOMPLETE_SETUP; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 861 | |
Liam R. Howlett | 2286a69 | 2023-01-20 11:26:18 -0500 | [diff] [blame] | 862 | vma_iter_init(&vmi, mm, vma->vm_start); |
| 863 | |
Nadav Amit | 4a18419 | 2022-05-09 18:20:50 -0700 | [diff] [blame] | 864 | tlb_gather_mmu(&tlb, mm); |
Liam R. Howlett | 2286a69 | 2023-01-20 11:26:18 -0500 | [diff] [blame] | 865 | ret = mprotect_fixup(&vmi, &tlb, vma, &prev, vma->vm_start, vma->vm_end, |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 866 | vm_flags); |
Nadav Amit | 4a18419 | 2022-05-09 18:20:50 -0700 | [diff] [blame] | 867 | tlb_finish_mmu(&tlb); |
| 868 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 869 | if (ret) |
| 870 | goto out_unlock; |
| 871 | BUG_ON(prev != vma); |
| 872 | |
Alexey Dobriyan | 47a2ebb | 2020-01-30 22:17:29 -0800 | [diff] [blame] | 873 | if (unlikely(vm_flags & VM_EXEC)) { |
| 874 | pr_warn_once("process '%pD4' started with executable stack\n", |
| 875 | bprm->file); |
| 876 | } |
| 877 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 878 | /* Move stack pages down in memory. */ |
| 879 | if (stack_shift) { |
| 880 | ret = shift_arg_pages(vma, stack_shift); |
Anton Blanchard | fc63cf2 | 2009-11-11 14:26:48 -0800 | [diff] [blame] | 881 | if (ret) |
| 882 | goto out_unlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 883 | } |
| 884 | |
Mel Gorman | a8bef8ff | 2010-05-24 14:32:24 -0700 | [diff] [blame] | 885 | /* mprotect_fixup is overkill to remove the temporary stack flags */ |
Suren Baghdasaryan | 1c71222 | 2023-01-26 11:37:49 -0800 | [diff] [blame] | 886 | vm_flags_clear(vma, VM_STACK_INCOMPLETE_SETUP); |
Mel Gorman | a8bef8ff | 2010-05-24 14:32:24 -0700 | [diff] [blame] | 887 | |
Michael Neuling | 5ef097dd | 2010-03-05 13:42:57 -0800 | [diff] [blame] | 888 | stack_expand = 131072UL; /* randomly 32*4k (or 2*64k) pages */ |
Michael Neuling | 803bf5e | 2010-02-10 13:56:42 -0800 | [diff] [blame] | 889 | stack_size = vma->vm_end - vma->vm_start; |
| 890 | /* |
| 891 | * Align this down to a page boundary as expand_stack |
| 892 | * will align it up. |
| 893 | */ |
Kees Cook | c31dbb14 | 2018-04-10 16:35:01 -0700 | [diff] [blame] | 894 | rlim_stack = bprm->rlim_stack.rlim_cur & PAGE_MASK; |
Rolf Eike Beer | bfb4a2b | 2022-10-19 09:32:35 +0200 | [diff] [blame] | 895 | |
| 896 | stack_expand = min(rlim_stack, stack_size + stack_expand); |
| 897 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 898 | #ifdef CONFIG_STACK_GROWSUP |
Rolf Eike Beer | bfb4a2b | 2022-10-19 09:32:35 +0200 | [diff] [blame] | 899 | stack_base = vma->vm_start + stack_expand; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 900 | #else |
Rolf Eike Beer | bfb4a2b | 2022-10-19 09:32:35 +0200 | [diff] [blame] | 901 | stack_base = vma->vm_end - stack_expand; |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 902 | #endif |
Eric B Munson | 3af9e85 | 2010-05-18 15:30:49 +0100 | [diff] [blame] | 903 | current->mm->start_stack = bprm->p; |
Linus Torvalds | 8d7071a | 2023-06-24 13:45:51 -0700 | [diff] [blame] | 904 | ret = expand_stack_locked(vma, stack_base); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 905 | if (ret) |
| 906 | ret = -EFAULT; |
| 907 | |
| 908 | out_unlock: |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 909 | mmap_write_unlock(mm); |
Anton Blanchard | fc63cf2 | 2009-11-11 14:26:48 -0800 | [diff] [blame] | 910 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 911 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 912 | EXPORT_SYMBOL(setup_arg_pages); |
| 913 | |
Nicolas Pitre | 7e7ec6a | 2016-07-24 11:30:18 -0400 | [diff] [blame] | 914 | #else |
| 915 | |
| 916 | /* |
| 917 | * Transfer the program arguments and environment from the holding pages |
| 918 | * onto the stack. The provided stack pointer is adjusted accordingly. |
| 919 | */ |
| 920 | int transfer_args_to_stack(struct linux_binprm *bprm, |
| 921 | unsigned long *sp_location) |
| 922 | { |
| 923 | unsigned long index, stop, sp; |
| 924 | int ret = 0; |
| 925 | |
| 926 | stop = bprm->p >> PAGE_SHIFT; |
| 927 | sp = *sp_location; |
| 928 | |
| 929 | for (index = MAX_ARG_PAGES - 1; index >= stop; index--) { |
| 930 | unsigned int offset = index == stop ? bprm->p & ~PAGE_MASK : 0; |
Fabio M. De Francesco | 3a608cf | 2022-08-03 20:28:56 +0200 | [diff] [blame] | 931 | char *src = kmap_local_page(bprm->page[index]) + offset; |
Nicolas Pitre | 7e7ec6a | 2016-07-24 11:30:18 -0400 | [diff] [blame] | 932 | sp -= PAGE_SIZE - offset; |
| 933 | if (copy_to_user((void *) sp, src, PAGE_SIZE - offset) != 0) |
| 934 | ret = -EFAULT; |
Fabio M. De Francesco | 3a608cf | 2022-08-03 20:28:56 +0200 | [diff] [blame] | 935 | kunmap_local(src); |
Nicolas Pitre | 7e7ec6a | 2016-07-24 11:30:18 -0400 | [diff] [blame] | 936 | if (ret) |
| 937 | goto out; |
| 938 | } |
| 939 | |
Max Filippov | 2aea94a | 2024-03-20 11:26:07 -0700 | [diff] [blame] | 940 | bprm->exec += *sp_location - MAX_ARG_PAGES * PAGE_SIZE; |
Nicolas Pitre | 7e7ec6a | 2016-07-24 11:30:18 -0400 | [diff] [blame] | 941 | *sp_location = sp; |
| 942 | |
| 943 | out: |
| 944 | return ret; |
| 945 | } |
| 946 | EXPORT_SYMBOL(transfer_args_to_stack); |
| 947 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 948 | #endif /* CONFIG_MMU */ |
| 949 | |
Kees Cook | bdd8f62 | 2022-09-16 17:11:18 -0700 | [diff] [blame] | 950 | /* |
| 951 | * On success, caller must call do_close_execat() on the returned |
| 952 | * struct file to close it. |
| 953 | */ |
David Drysdale | 51f39a1 | 2014-12-12 16:57:29 -0800 | [diff] [blame] | 954 | static struct file *do_open_execat(int fd, struct filename *name, int flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 955 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 956 | struct file *file; |
Christoph Hellwig | e56b6a5 | 2008-05-19 07:53:34 +0200 | [diff] [blame] | 957 | int err; |
David Drysdale | 51f39a1 | 2014-12-12 16:57:29 -0800 | [diff] [blame] | 958 | struct open_flags open_exec_flags = { |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 959 | .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC, |
Al Viro | 62fb4a1 | 2015-12-26 22:33:24 -0500 | [diff] [blame] | 960 | .acc_mode = MAY_EXEC, |
Al Viro | f9652e1 | 2013-06-11 08:23:01 +0400 | [diff] [blame] | 961 | .intent = LOOKUP_OPEN, |
| 962 | .lookup_flags = LOOKUP_FOLLOW, |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 963 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 964 | |
David Drysdale | 51f39a1 | 2014-12-12 16:57:29 -0800 | [diff] [blame] | 965 | if ((flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0) |
| 966 | return ERR_PTR(-EINVAL); |
| 967 | if (flags & AT_SYMLINK_NOFOLLOW) |
| 968 | open_exec_flags.lookup_flags &= ~LOOKUP_FOLLOW; |
| 969 | if (flags & AT_EMPTY_PATH) |
| 970 | open_exec_flags.lookup_flags |= LOOKUP_EMPTY; |
| 971 | |
| 972 | file = do_filp_open(fd, name, &open_exec_flags); |
Al Viro | 6e8341a | 2009-04-06 11:16:22 -0400 | [diff] [blame] | 973 | if (IS_ERR(file)) |
Christoph Hellwig | e56b6a5 | 2008-05-19 07:53:34 +0200 | [diff] [blame] | 974 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 975 | |
Kees Cook | 633fb6a | 2020-08-11 18:36:26 -0700 | [diff] [blame] | 976 | /* |
| 977 | * may_open() has already checked for this, so it should be |
| 978 | * impossible to trip now. But we need to be extra cautious |
| 979 | * and check again at the very end too. |
| 980 | */ |
Christoph Hellwig | e56b6a5 | 2008-05-19 07:53:34 +0200 | [diff] [blame] | 981 | err = -EACCES; |
Kees Cook | 0fd338b | 2020-08-11 18:36:30 -0700 | [diff] [blame] | 982 | if (WARN_ON_ONCE(!S_ISREG(file_inode(file)->i_mode) || |
| 983 | path_noexec(&file->f_path))) |
Al Viro | 6e8341a | 2009-04-06 11:16:22 -0400 | [diff] [blame] | 984 | goto exit; |
Christoph Hellwig | e56b6a5 | 2008-05-19 07:53:34 +0200 | [diff] [blame] | 985 | |
Al Viro | 6e8341a | 2009-04-06 11:16:22 -0400 | [diff] [blame] | 986 | out: |
Christoph Hellwig | e56b6a5 | 2008-05-19 07:53:34 +0200 | [diff] [blame] | 987 | return file; |
| 988 | |
Al Viro | 6e8341a | 2009-04-06 11:16:22 -0400 | [diff] [blame] | 989 | exit: |
| 990 | fput(file); |
Christoph Hellwig | e56b6a5 | 2008-05-19 07:53:34 +0200 | [diff] [blame] | 991 | return ERR_PTR(err); |
| 992 | } |
Linus Torvalds | c4ad8f9 | 2014-02-05 12:54:53 -0800 | [diff] [blame] | 993 | |
Kees Cook | bdd8f62 | 2022-09-16 17:11:18 -0700 | [diff] [blame] | 994 | /** |
| 995 | * open_exec - Open a path name for execution |
| 996 | * |
| 997 | * @name: path name to open with the intent of executing it. |
| 998 | * |
| 999 | * Returns ERR_PTR on failure or allocated struct file on success. |
| 1000 | * |
Christian Brauner | 2a010c4 | 2024-05-31 15:01:43 +0200 | [diff] [blame] | 1001 | * As this is a wrapper for the internal do_open_execat(). Also see |
Kees Cook | bdd8f62 | 2022-09-16 17:11:18 -0700 | [diff] [blame] | 1002 | * do_close_execat(). |
| 1003 | */ |
Linus Torvalds | c4ad8f9 | 2014-02-05 12:54:53 -0800 | [diff] [blame] | 1004 | struct file *open_exec(const char *name) |
| 1005 | { |
Paul Moore | 5168910 | 2015-01-22 00:00:03 -0500 | [diff] [blame] | 1006 | struct filename *filename = getname_kernel(name); |
| 1007 | struct file *f = ERR_CAST(filename); |
| 1008 | |
| 1009 | if (!IS_ERR(filename)) { |
| 1010 | f = do_open_execat(AT_FDCWD, filename, 0); |
| 1011 | putname(filename); |
| 1012 | } |
| 1013 | return f; |
Linus Torvalds | c4ad8f9 | 2014-02-05 12:54:53 -0800 | [diff] [blame] | 1014 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1015 | EXPORT_SYMBOL(open_exec); |
| 1016 | |
Eric W. Biederman | 987f20a | 2022-09-26 17:15:32 -0500 | [diff] [blame] | 1017 | #if defined(CONFIG_BINFMT_FLAT) || defined(CONFIG_BINFMT_ELF_FDPIC) |
Al Viro | 3dc20cb | 2013-04-13 20:31:37 -0400 | [diff] [blame] | 1018 | ssize_t read_code(struct file *file, unsigned long addr, loff_t pos, size_t len) |
| 1019 | { |
Al Viro | ec69557 | 2014-02-04 19:08:21 -0500 | [diff] [blame] | 1020 | ssize_t res = vfs_read(file, (void __user *)addr, len, &pos); |
Al Viro | 3dc20cb | 2013-04-13 20:31:37 -0400 | [diff] [blame] | 1021 | if (res > 0) |
Christoph Hellwig | bce2b68 | 2020-06-07 21:42:43 -0700 | [diff] [blame] | 1022 | flush_icache_user_range(addr, addr + len); |
Al Viro | 3dc20cb | 2013-04-13 20:31:37 -0400 | [diff] [blame] | 1023 | return res; |
| 1024 | } |
| 1025 | EXPORT_SYMBOL(read_code); |
Christoph Hellwig | 48304f7 | 2020-06-07 21:42:40 -0700 | [diff] [blame] | 1026 | #endif |
Al Viro | 3dc20cb | 2013-04-13 20:31:37 -0400 | [diff] [blame] | 1027 | |
Eric W. Biederman | eea9673 | 2020-03-25 10:03:36 -0500 | [diff] [blame] | 1028 | /* |
| 1029 | * Maps the mm_struct mm into the current task struct. |
Eric W. Biederman | f7cfd87 | 2020-12-03 14:12:00 -0600 | [diff] [blame] | 1030 | * On success, this function returns with exec_update_lock |
| 1031 | * held for writing. |
Eric W. Biederman | eea9673 | 2020-03-25 10:03:36 -0500 | [diff] [blame] | 1032 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1033 | static int exec_mmap(struct mm_struct *mm) |
| 1034 | { |
| 1035 | struct task_struct *tsk; |
Davidlohr Bueso | 615d6e8 | 2014-04-07 15:37:25 -0700 | [diff] [blame] | 1036 | struct mm_struct *old_mm, *active_mm; |
Eric W. Biederman | eea9673 | 2020-03-25 10:03:36 -0500 | [diff] [blame] | 1037 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1038 | |
| 1039 | /* Notify parent that we're no longer interested in the old VM */ |
| 1040 | tsk = current; |
| 1041 | old_mm = current->mm; |
Thomas Gleixner | 4610ba7 | 2019-11-06 22:55:38 +0100 | [diff] [blame] | 1042 | exec_mm_release(tsk, old_mm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1043 | |
Eric W. Biederman | f7cfd87 | 2020-12-03 14:12:00 -0600 | [diff] [blame] | 1044 | ret = down_write_killable(&tsk->signal->exec_update_lock); |
Eric W. Biederman | eea9673 | 2020-03-25 10:03:36 -0500 | [diff] [blame] | 1045 | if (ret) |
| 1046 | return ret; |
| 1047 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1048 | if (old_mm) { |
| 1049 | /* |
Eric W. Biederman | 7e3c4fb | 2021-09-03 10:26:05 -0500 | [diff] [blame] | 1050 | * If there is a pending fatal signal perhaps a signal |
| 1051 | * whose default action is to create a coredump get |
| 1052 | * out and die instead of going through with the exec. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1053 | */ |
Eric W. Biederman | 7e3c4fb | 2021-09-03 10:26:05 -0500 | [diff] [blame] | 1054 | ret = mmap_read_lock_killable(old_mm); |
| 1055 | if (ret) { |
Eric W. Biederman | f7cfd87 | 2020-12-03 14:12:00 -0600 | [diff] [blame] | 1056 | up_write(&tsk->signal->exec_update_lock); |
Eric W. Biederman | 7e3c4fb | 2021-09-03 10:26:05 -0500 | [diff] [blame] | 1057 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1058 | } |
| 1059 | } |
Eric W. Biederman | eea9673 | 2020-03-25 10:03:36 -0500 | [diff] [blame] | 1060 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1061 | task_lock(tsk); |
Mathieu Desnoyers | 227a4aa | 2019-09-19 13:37:02 -0400 | [diff] [blame] | 1062 | membarrier_exec_mmap(mm); |
Nicholas Piggin | d53c3df | 2020-09-14 14:52:16 +1000 | [diff] [blame] | 1063 | |
| 1064 | local_irq_disable(); |
| 1065 | active_mm = tsk->active_mm; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1066 | tsk->active_mm = mm; |
Nicholas Piggin | d53c3df | 2020-09-14 14:52:16 +1000 | [diff] [blame] | 1067 | tsk->mm = mm; |
Mathieu Desnoyers | af7f588 | 2022-11-22 15:39:09 -0500 | [diff] [blame] | 1068 | mm_init_cid(mm); |
Nicholas Piggin | d53c3df | 2020-09-14 14:52:16 +1000 | [diff] [blame] | 1069 | /* |
| 1070 | * This prevents preemption while active_mm is being loaded and |
| 1071 | * it and mm are being updated, which could cause problems for |
| 1072 | * lazy tlb mm refcounting when these are updated by context |
| 1073 | * switches. Not all architectures can handle irqs off over |
| 1074 | * activate_mm yet. |
| 1075 | */ |
| 1076 | if (!IS_ENABLED(CONFIG_ARCH_WANT_IRQS_OFF_ACTIVATE_MM)) |
| 1077 | local_irq_enable(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1078 | activate_mm(active_mm, mm); |
Nicholas Piggin | d53c3df | 2020-09-14 14:52:16 +1000 | [diff] [blame] | 1079 | if (IS_ENABLED(CONFIG_ARCH_WANT_IRQS_OFF_ACTIVATE_MM)) |
| 1080 | local_irq_enable(); |
Sebastian Andrzej Siewior | dda1c41 | 2022-10-26 15:48:30 +0200 | [diff] [blame] | 1081 | lru_gen_add_mm(mm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1082 | task_unlock(tsk); |
Yu Zhao | bd74fda | 2022-09-18 02:00:05 -0600 | [diff] [blame] | 1083 | lru_gen_use_mm(mm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1084 | if (old_mm) { |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 1085 | mmap_read_unlock(old_mm); |
Eric Sesterhenn | 7dddb12 | 2006-04-01 01:13:38 +0200 | [diff] [blame] | 1086 | BUG_ON(active_mm != old_mm); |
Oleg Nesterov | 701085b2 | 2012-03-19 17:04:01 +0100 | [diff] [blame] | 1087 | setmax_mm_hiwater_rss(&tsk->signal->maxrss, old_mm); |
Balbir Singh | 31a78f2 | 2008-09-28 23:09:31 +0100 | [diff] [blame] | 1088 | mm_update_next_owner(old_mm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1089 | mmput(old_mm); |
| 1090 | return 0; |
| 1091 | } |
Nicholas Piggin | aa464ba | 2023-02-03 17:18:34 +1000 | [diff] [blame] | 1092 | mmdrop_lazy_tlb(active_mm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1093 | return 0; |
| 1094 | } |
| 1095 | |
Arjan van de Ven | 858119e | 2006-01-14 13:20:43 -0800 | [diff] [blame] | 1096 | static int de_thread(struct task_struct *tsk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1097 | { |
| 1098 | struct signal_struct *sig = tsk->signal; |
Oleg Nesterov | b2c903b | 2007-10-16 23:27:22 -0700 | [diff] [blame] | 1099 | struct sighand_struct *oldsighand = tsk->sighand; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1100 | spinlock_t *lock = &oldsighand->siglock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1101 | |
Eric W. Biederman | aafe6c2 | 2006-09-27 01:51:13 -0700 | [diff] [blame] | 1102 | if (thread_group_empty(tsk)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1103 | goto no_thread_group; |
| 1104 | |
| 1105 | /* |
| 1106 | * Kill all other threads in the thread group. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1107 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1108 | spin_lock_irq(lock); |
Eric W. Biederman | 4969733 | 2021-06-24 02:14:30 -0500 | [diff] [blame] | 1109 | if ((sig->flags & SIGNAL_GROUP_EXIT) || sig->group_exec_task) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1110 | /* |
| 1111 | * Another group action in progress, just |
| 1112 | * return so that the signal is processed. |
| 1113 | */ |
| 1114 | spin_unlock_irq(lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1115 | return -EAGAIN; |
| 1116 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1117 | |
Eric W. Biederman | 60700e3 | 2021-06-06 13:47:53 -0500 | [diff] [blame] | 1118 | sig->group_exec_task = tsk; |
Oleg Nesterov | d344193 | 2010-05-26 14:43:11 -0700 | [diff] [blame] | 1119 | sig->notify_count = zap_other_threads(tsk); |
| 1120 | if (!thread_group_leader(tsk)) |
| 1121 | sig->notify_count--; |
| 1122 | |
| 1123 | while (sig->notify_count) { |
Oleg Nesterov | d5bbd43 | 2012-10-08 19:13:01 +0200 | [diff] [blame] | 1124 | __set_current_state(TASK_KILLABLE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1125 | spin_unlock_irq(lock); |
Rafael J. Wysocki | a72173e | 2018-12-03 13:04:18 +0100 | [diff] [blame] | 1126 | schedule(); |
Davidlohr Bueso | 08d405c | 2019-01-03 15:28:58 -0800 | [diff] [blame] | 1127 | if (__fatal_signal_pending(tsk)) |
Oleg Nesterov | d5bbd43 | 2012-10-08 19:13:01 +0200 | [diff] [blame] | 1128 | goto killed; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1129 | spin_lock_irq(lock); |
| 1130 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1131 | spin_unlock_irq(lock); |
| 1132 | |
| 1133 | /* |
| 1134 | * At this point all other threads have exited, all we have to |
| 1135 | * do is to wait for the thread group leader to become inactive, |
| 1136 | * and to assume its PID: |
| 1137 | */ |
Eric W. Biederman | aafe6c2 | 2006-09-27 01:51:13 -0700 | [diff] [blame] | 1138 | if (!thread_group_leader(tsk)) { |
Oleg Nesterov | 8187926 | 2008-12-01 14:18:16 -0800 | [diff] [blame] | 1139 | struct task_struct *leader = tsk->group_leader; |
Oleg Nesterov | 6db840f | 2007-10-16 23:27:23 -0700 | [diff] [blame] | 1140 | |
Oleg Nesterov | 6db840f | 2007-10-16 23:27:23 -0700 | [diff] [blame] | 1141 | for (;;) { |
Ingo Molnar | 780de9d | 2017-02-02 11:50:56 +0100 | [diff] [blame] | 1142 | cgroup_threadgroup_change_begin(tsk); |
Oleg Nesterov | 6db840f | 2007-10-16 23:27:23 -0700 | [diff] [blame] | 1143 | write_lock_irq(&tasklist_lock); |
Kirill Tkhai | dfcce79 | 2015-04-16 12:48:01 -0700 | [diff] [blame] | 1144 | /* |
| 1145 | * Do this under tasklist_lock to ensure that |
Eric W. Biederman | 60700e3 | 2021-06-06 13:47:53 -0500 | [diff] [blame] | 1146 | * exit_notify() can't miss ->group_exec_task |
Kirill Tkhai | dfcce79 | 2015-04-16 12:48:01 -0700 | [diff] [blame] | 1147 | */ |
| 1148 | sig->notify_count = -1; |
Oleg Nesterov | 6db840f | 2007-10-16 23:27:23 -0700 | [diff] [blame] | 1149 | if (likely(leader->exit_state)) |
| 1150 | break; |
Oleg Nesterov | d5bbd43 | 2012-10-08 19:13:01 +0200 | [diff] [blame] | 1151 | __set_current_state(TASK_KILLABLE); |
Oleg Nesterov | 6db840f | 2007-10-16 23:27:23 -0700 | [diff] [blame] | 1152 | write_unlock_irq(&tasklist_lock); |
Ingo Molnar | 780de9d | 2017-02-02 11:50:56 +0100 | [diff] [blame] | 1153 | cgroup_threadgroup_change_end(tsk); |
Rafael J. Wysocki | a72173e | 2018-12-03 13:04:18 +0100 | [diff] [blame] | 1154 | schedule(); |
Davidlohr Bueso | 08d405c | 2019-01-03 15:28:58 -0800 | [diff] [blame] | 1155 | if (__fatal_signal_pending(tsk)) |
Oleg Nesterov | d5bbd43 | 2012-10-08 19:13:01 +0200 | [diff] [blame] | 1156 | goto killed; |
Oleg Nesterov | 6db840f | 2007-10-16 23:27:23 -0700 | [diff] [blame] | 1157 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1158 | |
Roland McGrath | f5e9028 | 2006-04-10 22:54:16 -0700 | [diff] [blame] | 1159 | /* |
| 1160 | * The only record we have of the real-time age of a |
| 1161 | * process, regardless of execs it's done, is start_time. |
| 1162 | * All the past CPU time is accumulated in signal_struct |
| 1163 | * from sister threads now dead. But in this non-leader |
| 1164 | * exec, nothing survives from the original leader thread, |
| 1165 | * whose birth marks the true age of this process now. |
| 1166 | * When we take on its identity by switching to its PID, we |
| 1167 | * also take its birthdate (always earlier than our own). |
| 1168 | */ |
Eric W. Biederman | aafe6c2 | 2006-09-27 01:51:13 -0700 | [diff] [blame] | 1169 | tsk->start_time = leader->start_time; |
Peter Zijlstra | cf25e24 | 2019-11-07 11:07:58 +0100 | [diff] [blame] | 1170 | tsk->start_boottime = leader->start_boottime; |
Roland McGrath | f5e9028 | 2006-04-10 22:54:16 -0700 | [diff] [blame] | 1171 | |
Pavel Emelyanov | bac0abd | 2007-10-18 23:40:18 -0700 | [diff] [blame] | 1172 | BUG_ON(!same_thread_group(leader, tsk)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1173 | /* |
| 1174 | * An exec() starts a new thread group with the |
| 1175 | * TGID of the previous thread group. Rehash the |
| 1176 | * two threads with a switched PID, and release |
| 1177 | * the former thread group leader: |
| 1178 | */ |
Eric W. Biederman | d73d652 | 2006-03-28 16:11:03 -0800 | [diff] [blame] | 1179 | |
| 1180 | /* Become a process group leader with the old leader's pid. |
Eric W. Biederman | c18258c | 2006-09-27 01:51:06 -0700 | [diff] [blame] | 1181 | * The old leader becomes a thread of the this thread group. |
Eric W. Biederman | d73d652 | 2006-03-28 16:11:03 -0800 | [diff] [blame] | 1182 | */ |
Eric W. Biederman | 6b03d13 | 2020-04-19 06:35:02 -0500 | [diff] [blame] | 1183 | exchange_tids(tsk, leader); |
Eric W. Biederman | 6883f81 | 2017-06-04 04:32:13 -0500 | [diff] [blame] | 1184 | transfer_pid(leader, tsk, PIDTYPE_TGID); |
Eric W. Biederman | aafe6c2 | 2006-09-27 01:51:13 -0700 | [diff] [blame] | 1185 | transfer_pid(leader, tsk, PIDTYPE_PGID); |
| 1186 | transfer_pid(leader, tsk, PIDTYPE_SID); |
Oleg Nesterov | 9cd80bb | 2009-12-17 15:27:15 -0800 | [diff] [blame] | 1187 | |
Eric W. Biederman | aafe6c2 | 2006-09-27 01:51:13 -0700 | [diff] [blame] | 1188 | list_replace_rcu(&leader->tasks, &tsk->tasks); |
Oleg Nesterov | 9cd80bb | 2009-12-17 15:27:15 -0800 | [diff] [blame] | 1189 | list_replace_init(&leader->sibling, &tsk->sibling); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1190 | |
Eric W. Biederman | aafe6c2 | 2006-09-27 01:51:13 -0700 | [diff] [blame] | 1191 | tsk->group_leader = tsk; |
| 1192 | leader->group_leader = tsk; |
Eric W. Biederman | de12a78 | 2006-04-10 17:16:49 -0600 | [diff] [blame] | 1193 | |
Eric W. Biederman | aafe6c2 | 2006-09-27 01:51:13 -0700 | [diff] [blame] | 1194 | tsk->exit_signal = SIGCHLD; |
Oleg Nesterov | 087806b | 2011-06-22 23:10:26 +0200 | [diff] [blame] | 1195 | leader->exit_signal = -1; |
Oleg Nesterov | 962b564 | 2005-11-23 13:37:43 -0800 | [diff] [blame] | 1196 | |
| 1197 | BUG_ON(leader->exit_state != EXIT_ZOMBIE); |
| 1198 | leader->exit_state = EXIT_DEAD; |
Oleg Nesterov | eac1b5e | 2011-07-21 20:00:43 +0200 | [diff] [blame] | 1199 | /* |
| 1200 | * We are going to release_task()->ptrace_unlink() silently, |
| 1201 | * the tracer can sleep in do_wait(). EXIT_DEAD guarantees |
Zhang Jiaming | 5036793 | 2022-06-29 15:29:32 +0800 | [diff] [blame] | 1202 | * the tracer won't block again waiting for this thread. |
Oleg Nesterov | eac1b5e | 2011-07-21 20:00:43 +0200 | [diff] [blame] | 1203 | */ |
| 1204 | if (unlikely(leader->ptrace)) |
| 1205 | __wake_up_parent(leader, leader->parent); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1206 | write_unlock_irq(&tasklist_lock); |
Ingo Molnar | 780de9d | 2017-02-02 11:50:56 +0100 | [diff] [blame] | 1207 | cgroup_threadgroup_change_end(tsk); |
Oleg Nesterov | 8187926 | 2008-12-01 14:18:16 -0800 | [diff] [blame] | 1208 | |
| 1209 | release_task(leader); |
Oleg Nesterov | ed5d2ca | 2008-02-04 22:27:24 -0800 | [diff] [blame] | 1210 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1211 | |
Eric W. Biederman | 60700e3 | 2021-06-06 13:47:53 -0500 | [diff] [blame] | 1212 | sig->group_exec_task = NULL; |
Oleg Nesterov | 6db840f | 2007-10-16 23:27:23 -0700 | [diff] [blame] | 1213 | sig->notify_count = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1214 | |
| 1215 | no_thread_group: |
Oleg Nesterov | e636825 | 2012-03-19 17:03:22 +0100 | [diff] [blame] | 1216 | /* we have changed execution domain */ |
| 1217 | tsk->exit_signal = SIGCHLD; |
| 1218 | |
Eric W. Biederman | 0216915 | 2020-03-25 10:00:21 -0500 | [diff] [blame] | 1219 | BUG_ON(!thread_group_leader(tsk)); |
| 1220 | return 0; |
| 1221 | |
| 1222 | killed: |
| 1223 | /* protects against exit_notify() and __exit_signal() */ |
| 1224 | read_lock(&tasklist_lock); |
Eric W. Biederman | 60700e3 | 2021-06-06 13:47:53 -0500 | [diff] [blame] | 1225 | sig->group_exec_task = NULL; |
Eric W. Biederman | 0216915 | 2020-03-25 10:00:21 -0500 | [diff] [blame] | 1226 | sig->notify_count = 0; |
| 1227 | read_unlock(&tasklist_lock); |
| 1228 | return -EAGAIN; |
| 1229 | } |
| 1230 | |
| 1231 | |
Eric W. Biederman | 7a60ef4 | 2020-03-08 12:04:44 -0500 | [diff] [blame] | 1232 | /* |
| 1233 | * This function makes sure the current process has its own signal table, |
| 1234 | * so that flush_signal_handlers can later reset the handlers without |
| 1235 | * disturbing other processes. (Other processes might share the signal |
| 1236 | * table via the CLONE_SIGHAND option to clone().) |
| 1237 | */ |
Eric W. Biederman | 0216915 | 2020-03-25 10:00:21 -0500 | [diff] [blame] | 1238 | static int unshare_sighand(struct task_struct *me) |
| 1239 | { |
| 1240 | struct sighand_struct *oldsighand = me->sighand; |
Oleg Nesterov | 329f7db | 2005-11-07 21:12:43 +0300 | [diff] [blame] | 1241 | |
Elena Reshetova | d036bda | 2019-01-18 14:27:26 +0200 | [diff] [blame] | 1242 | if (refcount_read(&oldsighand->count) != 1) { |
Oleg Nesterov | b2c903b | 2007-10-16 23:27:22 -0700 | [diff] [blame] | 1243 | struct sighand_struct *newsighand; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1244 | /* |
Oleg Nesterov | b2c903b | 2007-10-16 23:27:22 -0700 | [diff] [blame] | 1245 | * This ->sighand is shared with the CLONE_SIGHAND |
| 1246 | * but not CLONE_THREAD task, switch to the new one. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1247 | */ |
Oleg Nesterov | b2c903b | 2007-10-16 23:27:22 -0700 | [diff] [blame] | 1248 | newsighand = kmem_cache_alloc(sighand_cachep, GFP_KERNEL); |
| 1249 | if (!newsighand) |
| 1250 | return -ENOMEM; |
| 1251 | |
Elena Reshetova | d036bda | 2019-01-18 14:27:26 +0200 | [diff] [blame] | 1252 | refcount_set(&newsighand->count, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1253 | |
| 1254 | write_lock_irq(&tasklist_lock); |
| 1255 | spin_lock(&oldsighand->siglock); |
Bernd Edlinger | 5bf2fed | 2021-06-07 15:54:27 +0200 | [diff] [blame] | 1256 | memcpy(newsighand->action, oldsighand->action, |
| 1257 | sizeof(newsighand->action)); |
Eric W. Biederman | 0216915 | 2020-03-25 10:00:21 -0500 | [diff] [blame] | 1258 | rcu_assign_pointer(me->sighand, newsighand); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1259 | spin_unlock(&oldsighand->siglock); |
| 1260 | write_unlock_irq(&tasklist_lock); |
| 1261 | |
Davide Libenzi | fba2afa | 2007-05-10 22:23:13 -0700 | [diff] [blame] | 1262 | __cleanup_sighand(oldsighand); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1263 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1264 | return 0; |
| 1265 | } |
Oleg Nesterov | 0840a90 | 2007-10-16 23:27:22 -0700 | [diff] [blame] | 1266 | |
Arnd Bergmann | 3756f64 | 2017-12-14 15:32:41 -0800 | [diff] [blame] | 1267 | char *__get_task_comm(char *buf, size_t buf_size, struct task_struct *tsk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1268 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1269 | task_lock(tsk); |
Yafang Shao | 503471a | 2022-01-19 18:08:22 -0800 | [diff] [blame] | 1270 | /* Always NUL terminated and zero-padded */ |
| 1271 | strscpy_pad(buf, tsk->comm, buf_size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1272 | task_unlock(tsk); |
Andrew Morton | 59714d6 | 2008-02-04 22:27:21 -0800 | [diff] [blame] | 1273 | return buf; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1274 | } |
Arnd Bergmann | 3756f64 | 2017-12-14 15:32:41 -0800 | [diff] [blame] | 1275 | EXPORT_SYMBOL_GPL(__get_task_comm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1276 | |
Al Viro | 6a6d27d | 2012-08-21 09:56:33 -0400 | [diff] [blame] | 1277 | /* |
| 1278 | * These functions flushes out all traces of the currently running executable |
| 1279 | * so that a new one can be started |
| 1280 | */ |
| 1281 | |
Adrian Hunter | 82b8977 | 2014-05-28 11:45:04 +0300 | [diff] [blame] | 1282 | void __set_task_comm(struct task_struct *tsk, const char *buf, bool exec) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1283 | { |
| 1284 | task_lock(tsk); |
KAMEZAWA Hiroyuki | 43d2b11 | 2012-01-10 15:08:09 -0800 | [diff] [blame] | 1285 | trace_task_rename(tsk, buf); |
Yafang Shao | 06c5088 | 2022-01-19 18:08:19 -0800 | [diff] [blame] | 1286 | strscpy_pad(tsk->comm, buf, sizeof(tsk->comm)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1287 | task_unlock(tsk); |
Adrian Hunter | 82b8977 | 2014-05-28 11:45:04 +0300 | [diff] [blame] | 1288 | perf_event_comm(tsk, exec); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1289 | } |
| 1290 | |
Kees Cook | a9208e4 | 2017-07-18 15:25:30 -0700 | [diff] [blame] | 1291 | /* |
| 1292 | * Calling this is the point of no return. None of the failures will be |
| 1293 | * seen by userspace since either the process is already taking a fatal |
| 1294 | * signal (via de_thread() or coredump), or will have SEGV raised |
Eric W. Biederman | 13c432b | 2020-03-19 17:16:12 -0500 | [diff] [blame] | 1295 | * (after exec_mmap()) by search_binary_handler (see below). |
Kees Cook | a9208e4 | 2017-07-18 15:25:30 -0700 | [diff] [blame] | 1296 | */ |
Eric W. Biederman | 2388777 | 2020-05-03 07:54:10 -0500 | [diff] [blame] | 1297 | int begin_new_exec(struct linux_binprm * bprm) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1298 | { |
Eric W. Biederman | 2ca7be7 | 2020-03-25 10:00:07 -0500 | [diff] [blame] | 1299 | struct task_struct *me = current; |
Linus Torvalds | 221af7f | 2010-01-28 22:14:42 -0800 | [diff] [blame] | 1300 | int retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1301 | |
Eric W. Biederman | 56305aa | 2020-05-29 22:00:54 -0500 | [diff] [blame] | 1302 | /* Once we are committed compute the creds */ |
| 1303 | retval = bprm_creds_from_file(bprm); |
| 1304 | if (retval) |
| 1305 | return retval; |
| 1306 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1307 | /* |
Marco Elver | c823899 | 2024-04-11 12:20:57 +0200 | [diff] [blame] | 1308 | * This tracepoint marks the point before flushing the old exec where |
| 1309 | * the current task is still unchanged, but errors are fatal (point of |
| 1310 | * no return). The later "sched_process_exec" tracepoint is called after |
| 1311 | * the current task has successfully switched to the new exec. |
| 1312 | */ |
| 1313 | trace_sched_prepare_exec(current, bprm); |
| 1314 | |
| 1315 | /* |
Eric W. Biederman | 6834e0b | 2020-04-04 12:01:37 -0500 | [diff] [blame] | 1316 | * Ensure all future errors are fatal. |
| 1317 | */ |
| 1318 | bprm->point_of_no_return = true; |
| 1319 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1320 | /* |
Eric W. Biederman | 0216915 | 2020-03-25 10:00:21 -0500 | [diff] [blame] | 1321 | * Make this the only thread in the thread group. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1322 | */ |
Eric W. Biederman | 2ca7be7 | 2020-03-25 10:00:07 -0500 | [diff] [blame] | 1323 | retval = de_thread(me); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1324 | if (retval) |
| 1325 | goto out; |
| 1326 | |
Davidlohr Bueso | 6e399cd | 2015-04-16 12:47:59 -0700 | [diff] [blame] | 1327 | /* |
Eric W. Biederman | 9ee1206 | 2020-11-30 16:58:46 -0600 | [diff] [blame] | 1328 | * Cancel any io_uring activity across execve |
| 1329 | */ |
| 1330 | io_uring_task_cancel(); |
| 1331 | |
Eric W. Biederman | b604350 | 2020-11-20 17:14:18 -0600 | [diff] [blame] | 1332 | /* Ensure the files table is not shared. */ |
Eric W. Biederman | 1f702603 | 2020-11-20 17:14:19 -0600 | [diff] [blame] | 1333 | retval = unshare_files(); |
Eric W. Biederman | b604350 | 2020-11-20 17:14:18 -0600 | [diff] [blame] | 1334 | if (retval) |
| 1335 | goto out; |
Eric W. Biederman | b604350 | 2020-11-20 17:14:18 -0600 | [diff] [blame] | 1336 | |
Davidlohr Bueso | 6e399cd | 2015-04-16 12:47:59 -0700 | [diff] [blame] | 1337 | /* |
| 1338 | * Must be called _before_ exec_mmap() as bprm->mm is |
Mateusz Guzik | a7031f1 | 2023-08-14 19:21:40 +0200 | [diff] [blame] | 1339 | * not visible until then. Doing it here also ensures |
| 1340 | * we don't race against replace_mm_exe_file(). |
Davidlohr Bueso | 6e399cd | 2015-04-16 12:47:59 -0700 | [diff] [blame] | 1341 | */ |
David Hildenbrand | fe69d56 | 2021-04-23 10:29:59 +0200 | [diff] [blame] | 1342 | retval = set_mm_exe_file(bprm->mm, bprm->file); |
| 1343 | if (retval) |
| 1344 | goto out; |
Davidlohr Bueso | 6e399cd | 2015-04-16 12:47:59 -0700 | [diff] [blame] | 1345 | |
Eric W. Biederman | b8a61c9 | 2020-05-14 15:17:40 -0500 | [diff] [blame] | 1346 | /* If the binary is not readable then enforce mm->dumpable=0 */ |
Eric W. Biederman | f87d1c9 | 2020-05-16 16:29:20 -0500 | [diff] [blame] | 1347 | would_dump(bprm, bprm->file); |
Eric W. Biederman | b8a61c9 | 2020-05-14 15:17:40 -0500 | [diff] [blame] | 1348 | if (bprm->have_execfd) |
| 1349 | would_dump(bprm, bprm->executable); |
Eric W. Biederman | f87d1c9 | 2020-05-16 16:29:20 -0500 | [diff] [blame] | 1350 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1351 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1352 | * Release all of the old mmap stuff |
| 1353 | */ |
Oleg Nesterov | 3c77f84 | 2010-11-30 20:55:34 +0100 | [diff] [blame] | 1354 | acct_arg_size(bprm, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1355 | retval = exec_mmap(bprm->mm); |
| 1356 | if (retval) |
Al Viro | fd8328b | 2008-04-22 05:11:59 -0400 | [diff] [blame] | 1357 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1358 | |
Kees Cook | a9208e4 | 2017-07-18 15:25:30 -0700 | [diff] [blame] | 1359 | bprm->mm = NULL; |
Linus Torvalds | 7ab02af | 2010-02-02 12:37:44 -0800 | [diff] [blame] | 1360 | |
Andrei Vagin | 2b5f9da | 2022-09-20 17:31:19 -0700 | [diff] [blame] | 1361 | retval = exec_task_namespaces(); |
| 1362 | if (retval) |
| 1363 | goto out_unlock; |
| 1364 | |
Eric W. Biederman | ccf0fa6 | 2020-03-25 10:03:21 -0500 | [diff] [blame] | 1365 | #ifdef CONFIG_POSIX_TIMERS |
Thadeu Lima de Souza Cascardo | e362359 | 2022-08-09 14:07:51 -0300 | [diff] [blame] | 1366 | spin_lock_irq(&me->sighand->siglock); |
| 1367 | posix_cpu_timers_exit(me); |
| 1368 | spin_unlock_irq(&me->sighand->siglock); |
Oleg Nesterov | d5b36a4 | 2022-07-11 18:16:25 +0200 | [diff] [blame] | 1369 | exit_itimers(me); |
Eric W. Biederman | ccf0fa6 | 2020-03-25 10:03:21 -0500 | [diff] [blame] | 1370 | flush_itimer_signals(); |
| 1371 | #endif |
| 1372 | |
| 1373 | /* |
| 1374 | * Make the signal table private. |
| 1375 | */ |
| 1376 | retval = unshare_sighand(me); |
| 1377 | if (retval) |
Eric W. Biederman | 89826cc | 2020-04-02 18:04:54 -0500 | [diff] [blame] | 1378 | goto out_unlock; |
Eric W. Biederman | ccf0fa6 | 2020-03-25 10:03:21 -0500 | [diff] [blame] | 1379 | |
Eric W. Biederman | 1b2552c | 2022-04-11 14:15:54 -0500 | [diff] [blame] | 1380 | me->flags &= ~(PF_RANDOMIZE | PF_FORKNOEXEC | |
Zhang Yi | b88fae6 | 2014-01-23 15:55:57 -0800 | [diff] [blame] | 1381 | PF_NOFREEZE | PF_NO_SETAFFINITY); |
Linus Torvalds | 7ab02af | 2010-02-02 12:37:44 -0800 | [diff] [blame] | 1382 | flush_thread(); |
Eric W. Biederman | 2ca7be7 | 2020-03-25 10:00:07 -0500 | [diff] [blame] | 1383 | me->personality &= ~bprm->per_clear; |
Linus Torvalds | 7ab02af | 2010-02-02 12:37:44 -0800 | [diff] [blame] | 1384 | |
Gabriel Krisman Bertazi | 1446e1d | 2020-11-27 14:32:34 -0500 | [diff] [blame] | 1385 | clear_syscall_work_syscall_user_dispatch(me); |
| 1386 | |
Aleksa Sarai | 613cc2b | 2016-12-21 16:26:24 +1100 | [diff] [blame] | 1387 | /* |
| 1388 | * We have to apply CLOEXEC before we change whether the process is |
| 1389 | * dumpable (in setup_new_exec) to avoid a race with a process in userspace |
| 1390 | * trying to access the should-be-closed file descriptors of a process |
| 1391 | * undergoing exec(2). |
| 1392 | */ |
Eric W. Biederman | 2ca7be7 | 2020-03-25 10:00:07 -0500 | [diff] [blame] | 1393 | do_close_on_exec(me->files); |
Eric W. Biederman | df9e4d2 | 2020-05-03 07:15:28 -0500 | [diff] [blame] | 1394 | |
Eric W. Biederman | df9e4d2 | 2020-05-03 07:15:28 -0500 | [diff] [blame] | 1395 | if (bprm->secureexec) { |
| 1396 | /* Make sure parent cannot signal privileged process. */ |
| 1397 | me->pdeath_signal = 0; |
| 1398 | |
| 1399 | /* |
| 1400 | * For secureexec, reset the stack limit to sane default to |
| 1401 | * avoid bad behavior from the prior rlimits. This has to |
| 1402 | * happen before arch_pick_mmap_layout(), which examines |
| 1403 | * RLIMIT_STACK, but after the point of no return to avoid |
| 1404 | * needing to clean up the change on failure. |
| 1405 | */ |
| 1406 | if (bprm->rlim_stack.rlim_cur > _STK_LIM) |
| 1407 | bprm->rlim_stack.rlim_cur = _STK_LIM; |
| 1408 | } |
| 1409 | |
| 1410 | me->sas_ss_sp = me->sas_ss_size = 0; |
| 1411 | |
| 1412 | /* |
| 1413 | * Figure out dumpability. Note that this checking only of current |
| 1414 | * is wrong, but userspace depends on it. This should be testing |
| 1415 | * bprm->secureexec instead. |
| 1416 | */ |
| 1417 | if (bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP || |
| 1418 | !(uid_eq(current_euid(), current_uid()) && |
| 1419 | gid_eq(current_egid(), current_gid()))) |
| 1420 | set_dumpable(current->mm, suid_dumpable); |
| 1421 | else |
| 1422 | set_dumpable(current->mm, SUID_DUMP_USER); |
| 1423 | |
| 1424 | perf_event_exec(); |
| 1425 | __set_task_comm(me, kbasename(bprm->filename), true); |
| 1426 | |
| 1427 | /* An exec changes our domain. We are no longer part of the thread |
| 1428 | group */ |
| 1429 | WRITE_ONCE(me->self_exec_id, me->self_exec_id + 1); |
| 1430 | flush_signal_handlers(me, 0); |
| 1431 | |
Alexey Gladkov | 905ae01 | 2021-04-22 14:27:09 +0200 | [diff] [blame] | 1432 | retval = set_cred_ucounts(bprm->cred); |
| 1433 | if (retval < 0) |
| 1434 | goto out_unlock; |
| 1435 | |
Eric W. Biederman | df9e4d2 | 2020-05-03 07:15:28 -0500 | [diff] [blame] | 1436 | /* |
| 1437 | * install the new credentials for this executable |
| 1438 | */ |
| 1439 | security_bprm_committing_creds(bprm); |
| 1440 | |
| 1441 | commit_creds(bprm->cred); |
| 1442 | bprm->cred = NULL; |
| 1443 | |
| 1444 | /* |
| 1445 | * Disable monitoring for regular users |
| 1446 | * when executing setuid binaries. Must |
| 1447 | * wait until new credentials are committed |
| 1448 | * by commit_creds() above |
| 1449 | */ |
| 1450 | if (get_dumpable(me->mm) != SUID_DUMP_USER) |
| 1451 | perf_event_exit_task(me); |
| 1452 | /* |
| 1453 | * cred_guard_mutex must be held at least to this point to prevent |
| 1454 | * ptrace_attach() from altering our determination of the task's |
| 1455 | * credentials; any time after this it may be unlocked. |
| 1456 | */ |
| 1457 | security_bprm_committed_creds(bprm); |
Eric W. Biederman | b8a61c9 | 2020-05-14 15:17:40 -0500 | [diff] [blame] | 1458 | |
| 1459 | /* Pass the opened binary to the interpreter. */ |
| 1460 | if (bprm->have_execfd) { |
| 1461 | retval = get_unused_fd_flags(0); |
| 1462 | if (retval < 0) |
| 1463 | goto out_unlock; |
| 1464 | fd_install(retval, bprm->executable); |
| 1465 | bprm->executable = NULL; |
| 1466 | bprm->execfd = retval; |
| 1467 | } |
Linus Torvalds | 221af7f | 2010-01-28 22:14:42 -0800 | [diff] [blame] | 1468 | return 0; |
| 1469 | |
Eric W. Biederman | 89826cc | 2020-04-02 18:04:54 -0500 | [diff] [blame] | 1470 | out_unlock: |
Eric W. Biederman | f7cfd87 | 2020-12-03 14:12:00 -0600 | [diff] [blame] | 1471 | up_write(&me->signal->exec_update_lock); |
Bernd Edlinger | 84c39ec5 | 2024-01-22 19:34:21 +0100 | [diff] [blame] | 1472 | if (!bprm->cred) |
| 1473 | mutex_unlock(&me->signal->cred_guard_mutex); |
| 1474 | |
Linus Torvalds | 221af7f | 2010-01-28 22:14:42 -0800 | [diff] [blame] | 1475 | out: |
| 1476 | return retval; |
| 1477 | } |
Eric W. Biederman | 2388777 | 2020-05-03 07:54:10 -0500 | [diff] [blame] | 1478 | EXPORT_SYMBOL(begin_new_exec); |
Linus Torvalds | 221af7f | 2010-01-28 22:14:42 -0800 | [diff] [blame] | 1479 | |
Al Viro | 1b5d783 | 2011-06-19 12:49:47 -0400 | [diff] [blame] | 1480 | void would_dump(struct linux_binprm *bprm, struct file *file) |
| 1481 | { |
Eric W. Biederman | f84df2a | 2016-11-16 22:06:51 -0600 | [diff] [blame] | 1482 | struct inode *inode = file_inode(file); |
Christian Brauner | 4609e1f | 2023-01-13 12:49:22 +0100 | [diff] [blame] | 1483 | struct mnt_idmap *idmap = file_mnt_idmap(file); |
Christian Brauner | 4609e1f | 2023-01-13 12:49:22 +0100 | [diff] [blame] | 1484 | if (inode_permission(idmap, inode, MAY_READ) < 0) { |
Eric W. Biederman | f84df2a | 2016-11-16 22:06:51 -0600 | [diff] [blame] | 1485 | struct user_namespace *old, *user_ns; |
Al Viro | 1b5d783 | 2011-06-19 12:49:47 -0400 | [diff] [blame] | 1486 | bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP; |
Eric W. Biederman | f84df2a | 2016-11-16 22:06:51 -0600 | [diff] [blame] | 1487 | |
| 1488 | /* Ensure mm->user_ns contains the executable */ |
| 1489 | user_ns = old = bprm->mm->user_ns; |
| 1490 | while ((user_ns != &init_user_ns) && |
Christian Brauner | 9452e93 | 2023-01-13 12:49:27 +0100 | [diff] [blame] | 1491 | !privileged_wrt_inode_uidgid(user_ns, idmap, inode)) |
Eric W. Biederman | f84df2a | 2016-11-16 22:06:51 -0600 | [diff] [blame] | 1492 | user_ns = user_ns->parent; |
| 1493 | |
| 1494 | if (old != user_ns) { |
| 1495 | bprm->mm->user_ns = get_user_ns(user_ns); |
| 1496 | put_user_ns(old); |
| 1497 | } |
| 1498 | } |
Al Viro | 1b5d783 | 2011-06-19 12:49:47 -0400 | [diff] [blame] | 1499 | } |
| 1500 | EXPORT_SYMBOL(would_dump); |
| 1501 | |
Linus Torvalds | 221af7f | 2010-01-28 22:14:42 -0800 | [diff] [blame] | 1502 | void setup_new_exec(struct linux_binprm * bprm) |
| 1503 | { |
Eric W. Biederman | df9e4d2 | 2020-05-03 07:15:28 -0500 | [diff] [blame] | 1504 | /* Setup things that can depend upon the personality */ |
Eric W. Biederman | 7d503fe | 2020-04-02 18:35:14 -0500 | [diff] [blame] | 1505 | struct task_struct *me = current; |
Kees Cook | 46d98eb | 2017-07-18 15:25:27 -0700 | [diff] [blame] | 1506 | |
Eric W. Biederman | 7d503fe | 2020-04-02 18:35:14 -0500 | [diff] [blame] | 1507 | arch_pick_mmap_layout(me->mm, &bprm->rlim_stack); |
Alan Cox | d6e7114 | 2005-06-23 00:09:43 -0700 | [diff] [blame] | 1508 | |
Kyle Huey | e9ea1e7 | 2017-03-20 01:16:26 -0700 | [diff] [blame] | 1509 | arch_setup_new_exec(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1510 | |
Benjamin Herrenschmidt | 0551fbd | 2006-02-28 16:59:19 -0800 | [diff] [blame] | 1511 | /* Set the new mm task size. We have to do that late because it may |
| 1512 | * depend on TIF_32BIT which is only updated in flush_thread() on |
| 1513 | * some architectures like powerpc |
| 1514 | */ |
Eric W. Biederman | 7d503fe | 2020-04-02 18:35:14 -0500 | [diff] [blame] | 1515 | me->mm->task_size = TASK_SIZE; |
Eric W. Biederman | f7cfd87 | 2020-12-03 14:12:00 -0600 | [diff] [blame] | 1516 | up_write(&me->signal->exec_update_lock); |
Eric W. Biederman | 7d503fe | 2020-04-02 18:35:14 -0500 | [diff] [blame] | 1517 | mutex_unlock(&me->signal->cred_guard_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1518 | } |
Linus Torvalds | 221af7f | 2010-01-28 22:14:42 -0800 | [diff] [blame] | 1519 | EXPORT_SYMBOL(setup_new_exec); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1520 | |
Kees Cook | b838383 | 2018-04-10 16:34:57 -0700 | [diff] [blame] | 1521 | /* Runs immediately before start_thread() takes over. */ |
| 1522 | void finalize_exec(struct linux_binprm *bprm) |
| 1523 | { |
Kees Cook | c31dbb14 | 2018-04-10 16:35:01 -0700 | [diff] [blame] | 1524 | /* Store any stack rlimit changes before starting thread. */ |
| 1525 | task_lock(current->group_leader); |
| 1526 | current->signal->rlim[RLIMIT_STACK] = bprm->rlim_stack; |
| 1527 | task_unlock(current->group_leader); |
Kees Cook | b838383 | 2018-04-10 16:34:57 -0700 | [diff] [blame] | 1528 | } |
| 1529 | EXPORT_SYMBOL(finalize_exec); |
| 1530 | |
David Howells | a6f76f2 | 2008-11-14 10:39:24 +1100 | [diff] [blame] | 1531 | /* |
Oleg Nesterov | a2a8474 | 2009-09-05 11:17:13 -0700 | [diff] [blame] | 1532 | * Prepare credentials and lock ->cred_guard_mutex. |
Eric W. Biederman | 96ecee2 | 2020-05-03 06:48:17 -0500 | [diff] [blame] | 1533 | * setup_new_exec() commits the new creds and drops the lock. |
Randy Dunlap | 3d742d4 | 2021-02-24 12:00:48 -0800 | [diff] [blame] | 1534 | * Or, if exec fails before, free_bprm() should release ->cred |
Oleg Nesterov | a2a8474 | 2009-09-05 11:17:13 -0700 | [diff] [blame] | 1535 | * and unlock. |
| 1536 | */ |
Chanho Min | 4addd26 | 2018-12-10 16:49:54 +0900 | [diff] [blame] | 1537 | static int prepare_bprm_creds(struct linux_binprm *bprm) |
Oleg Nesterov | a2a8474 | 2009-09-05 11:17:13 -0700 | [diff] [blame] | 1538 | { |
KOSAKI Motohiro | 9b1bf12 | 2010-10-27 15:34:08 -0700 | [diff] [blame] | 1539 | if (mutex_lock_interruptible(¤t->signal->cred_guard_mutex)) |
Oleg Nesterov | a2a8474 | 2009-09-05 11:17:13 -0700 | [diff] [blame] | 1540 | return -ERESTARTNOINTR; |
| 1541 | |
| 1542 | bprm->cred = prepare_exec_creds(); |
| 1543 | if (likely(bprm->cred)) |
| 1544 | return 0; |
| 1545 | |
KOSAKI Motohiro | 9b1bf12 | 2010-10-27 15:34:08 -0700 | [diff] [blame] | 1546 | mutex_unlock(¤t->signal->cred_guard_mutex); |
Oleg Nesterov | a2a8474 | 2009-09-05 11:17:13 -0700 | [diff] [blame] | 1547 | return -ENOMEM; |
| 1548 | } |
| 1549 | |
Kees Cook | bdd8f62 | 2022-09-16 17:11:18 -0700 | [diff] [blame] | 1550 | /* Matches do_open_execat() */ |
| 1551 | static void do_close_execat(struct file *file) |
| 1552 | { |
Christian Brauner | 2a010c4 | 2024-05-31 15:01:43 +0200 | [diff] [blame] | 1553 | if (file) |
| 1554 | fput(file); |
Kees Cook | bdd8f62 | 2022-09-16 17:11:18 -0700 | [diff] [blame] | 1555 | } |
| 1556 | |
Linus Torvalds | c4ad8f9 | 2014-02-05 12:54:53 -0800 | [diff] [blame] | 1557 | static void free_bprm(struct linux_binprm *bprm) |
Oleg Nesterov | a2a8474 | 2009-09-05 11:17:13 -0700 | [diff] [blame] | 1558 | { |
Eric W. Biederman | f18ac55 | 2020-07-10 15:54:54 -0500 | [diff] [blame] | 1559 | if (bprm->mm) { |
| 1560 | acct_arg_size(bprm, 0); |
| 1561 | mmput(bprm->mm); |
| 1562 | } |
Oleg Nesterov | a2a8474 | 2009-09-05 11:17:13 -0700 | [diff] [blame] | 1563 | free_arg_pages(bprm); |
| 1564 | if (bprm->cred) { |
KOSAKI Motohiro | 9b1bf12 | 2010-10-27 15:34:08 -0700 | [diff] [blame] | 1565 | mutex_unlock(¤t->signal->cred_guard_mutex); |
Oleg Nesterov | a2a8474 | 2009-09-05 11:17:13 -0700 | [diff] [blame] | 1566 | abort_creds(bprm->cred); |
| 1567 | } |
Kees Cook | bdd8f62 | 2022-09-16 17:11:18 -0700 | [diff] [blame] | 1568 | do_close_execat(bprm->file); |
Eric W. Biederman | b8a61c9 | 2020-05-14 15:17:40 -0500 | [diff] [blame] | 1569 | if (bprm->executable) |
| 1570 | fput(bprm->executable); |
Kees Cook | b66c598 | 2012-12-20 15:05:16 -0800 | [diff] [blame] | 1571 | /* If a binfmt changed the interp, free it. */ |
| 1572 | if (bprm->interp != bprm->filename) |
| 1573 | kfree(bprm->interp); |
Eric W. Biederman | 60d9ad1 | 2020-07-11 08:16:15 -0500 | [diff] [blame] | 1574 | kfree(bprm->fdpath); |
Oleg Nesterov | a2a8474 | 2009-09-05 11:17:13 -0700 | [diff] [blame] | 1575 | kfree(bprm); |
| 1576 | } |
| 1577 | |
Linus Torvalds | 978ffcb | 2024-01-08 16:43:04 -0800 | [diff] [blame] | 1578 | static struct linux_binprm *alloc_bprm(int fd, struct filename *filename, int flags) |
Eric W. Biederman | 0a8f36e | 2020-07-10 15:39:45 -0500 | [diff] [blame] | 1579 | { |
Linus Torvalds | 978ffcb | 2024-01-08 16:43:04 -0800 | [diff] [blame] | 1580 | struct linux_binprm *bprm; |
| 1581 | struct file *file; |
Eric W. Biederman | 60d9ad1 | 2020-07-11 08:16:15 -0500 | [diff] [blame] | 1582 | int retval = -ENOMEM; |
Linus Torvalds | 978ffcb | 2024-01-08 16:43:04 -0800 | [diff] [blame] | 1583 | |
| 1584 | file = do_open_execat(fd, filename, flags); |
| 1585 | if (IS_ERR(file)) |
| 1586 | return ERR_CAST(file); |
| 1587 | |
| 1588 | bprm = kzalloc(sizeof(*bprm), GFP_KERNEL); |
| 1589 | if (!bprm) { |
Kees Cook | bdd8f62 | 2022-09-16 17:11:18 -0700 | [diff] [blame] | 1590 | do_close_execat(file); |
Linus Torvalds | 978ffcb | 2024-01-08 16:43:04 -0800 | [diff] [blame] | 1591 | return ERR_PTR(-ENOMEM); |
| 1592 | } |
| 1593 | |
| 1594 | bprm->file = file; |
Eric W. Biederman | 60d9ad1 | 2020-07-11 08:16:15 -0500 | [diff] [blame] | 1595 | |
| 1596 | if (fd == AT_FDCWD || filename->name[0] == '/') { |
| 1597 | bprm->filename = filename->name; |
| 1598 | } else { |
| 1599 | if (filename->name[0] == '\0') |
| 1600 | bprm->fdpath = kasprintf(GFP_KERNEL, "/dev/fd/%d", fd); |
| 1601 | else |
| 1602 | bprm->fdpath = kasprintf(GFP_KERNEL, "/dev/fd/%d/%s", |
| 1603 | fd, filename->name); |
| 1604 | if (!bprm->fdpath) |
| 1605 | goto out_free; |
| 1606 | |
Linus Torvalds | 978ffcb | 2024-01-08 16:43:04 -0800 | [diff] [blame] | 1607 | /* |
| 1608 | * Record that a name derived from an O_CLOEXEC fd will be |
| 1609 | * inaccessible after exec. This allows the code in exec to |
| 1610 | * choose to fail when the executable is not mmaped into the |
| 1611 | * interpreter and an open file descriptor is not passed to |
| 1612 | * the interpreter. This makes for a better user experience |
| 1613 | * than having the interpreter start and then immediately fail |
| 1614 | * when it finds the executable is inaccessible. |
| 1615 | */ |
| 1616 | if (get_close_on_exec(fd)) |
| 1617 | bprm->interp_flags |= BINPRM_FLAGS_PATH_INACCESSIBLE; |
| 1618 | |
Eric W. Biederman | 60d9ad1 | 2020-07-11 08:16:15 -0500 | [diff] [blame] | 1619 | bprm->filename = bprm->fdpath; |
| 1620 | } |
| 1621 | bprm->interp = bprm->filename; |
Eric W. Biederman | f18ac55 | 2020-07-10 15:54:54 -0500 | [diff] [blame] | 1622 | |
| 1623 | retval = bprm_mm_init(bprm); |
Linus Torvalds | 978ffcb | 2024-01-08 16:43:04 -0800 | [diff] [blame] | 1624 | if (!retval) |
| 1625 | return bprm; |
Eric W. Biederman | 60d9ad1 | 2020-07-11 08:16:15 -0500 | [diff] [blame] | 1626 | |
| 1627 | out_free: |
| 1628 | free_bprm(bprm); |
Eric W. Biederman | 60d9ad1 | 2020-07-11 08:16:15 -0500 | [diff] [blame] | 1629 | return ERR_PTR(retval); |
Eric W. Biederman | 0a8f36e | 2020-07-10 15:39:45 -0500 | [diff] [blame] | 1630 | } |
| 1631 | |
Oleg Nesterov | c2315c1 | 2017-10-03 16:15:42 -0700 | [diff] [blame] | 1632 | int bprm_change_interp(const char *interp, struct linux_binprm *bprm) |
Kees Cook | b66c598 | 2012-12-20 15:05:16 -0800 | [diff] [blame] | 1633 | { |
| 1634 | /* If a binfmt changed the interp, free it first. */ |
| 1635 | if (bprm->interp != bprm->filename) |
| 1636 | kfree(bprm->interp); |
| 1637 | bprm->interp = kstrdup(interp, GFP_KERNEL); |
| 1638 | if (!bprm->interp) |
| 1639 | return -ENOMEM; |
| 1640 | return 0; |
| 1641 | } |
| 1642 | EXPORT_SYMBOL(bprm_change_interp); |
| 1643 | |
Oleg Nesterov | a2a8474 | 2009-09-05 11:17:13 -0700 | [diff] [blame] | 1644 | /* |
David Howells | a6f76f2 | 2008-11-14 10:39:24 +1100 | [diff] [blame] | 1645 | * determine how safe it is to execute the proposed program |
KOSAKI Motohiro | 9b1bf12 | 2010-10-27 15:34:08 -0700 | [diff] [blame] | 1646 | * - the caller must hold ->cred_guard_mutex to protect against |
Kees Cook | c2e1f2e | 2014-06-05 00:23:17 -0700 | [diff] [blame] | 1647 | * PTRACE_ATTACH or seccomp thread-sync |
David Howells | a6f76f2 | 2008-11-14 10:39:24 +1100 | [diff] [blame] | 1648 | */ |
Oleg Nesterov | 9e00cdb | 2014-01-23 15:55:50 -0800 | [diff] [blame] | 1649 | static void check_unsafe_exec(struct linux_binprm *bprm) |
David Howells | a6f76f2 | 2008-11-14 10:39:24 +1100 | [diff] [blame] | 1650 | { |
David Howells | 0bf2f3a | 2009-02-06 11:45:46 +0000 | [diff] [blame] | 1651 | struct task_struct *p = current, *t; |
Al Viro | f1191b5 | 2009-03-30 07:35:18 -0400 | [diff] [blame] | 1652 | unsigned n_fs; |
David Howells | a6f76f2 | 2008-11-14 10:39:24 +1100 | [diff] [blame] | 1653 | |
Eric W. Biederman | 9227dd2 | 2017-01-23 17:26:31 +1300 | [diff] [blame] | 1654 | if (p->ptrace) |
| 1655 | bprm->unsafe |= LSM_UNSAFE_PTRACE; |
David Howells | a6f76f2 | 2008-11-14 10:39:24 +1100 | [diff] [blame] | 1656 | |
Andy Lutomirski | 259e5e6 | 2012-04-12 16:47:50 -0500 | [diff] [blame] | 1657 | /* |
| 1658 | * This isn't strictly necessary, but it makes it harder for LSMs to |
| 1659 | * mess up. |
| 1660 | */ |
Kees Cook | 1d4457f | 2014-05-21 15:23:46 -0700 | [diff] [blame] | 1661 | if (task_no_new_privs(current)) |
Andy Lutomirski | 259e5e6 | 2012-04-12 16:47:50 -0500 | [diff] [blame] | 1662 | bprm->unsafe |= LSM_UNSAFE_NO_NEW_PRIVS; |
| 1663 | |
Kees Cook | 275498a | 2022-10-18 00:17:24 -0700 | [diff] [blame] | 1664 | /* |
| 1665 | * If another task is sharing our fs, we cannot safely |
| 1666 | * suid exec because the differently privileged task |
| 1667 | * will be able to manipulate the current directory, etc. |
| 1668 | * It would be nice to force an unshare instead... |
| 1669 | */ |
David Howells | 0bf2f3a | 2009-02-06 11:45:46 +0000 | [diff] [blame] | 1670 | n_fs = 1; |
Nick Piggin | 2a4419b | 2010-08-18 04:37:33 +1000 | [diff] [blame] | 1671 | spin_lock(&p->fs->lock); |
Oleg Nesterov | 437f7fd | 2009-04-24 01:02:45 +0200 | [diff] [blame] | 1672 | rcu_read_lock(); |
Oleg Nesterov | 61a7a5e | 2023-10-30 16:57:10 +0100 | [diff] [blame] | 1673 | for_other_threads(p, t) { |
David Howells | 0bf2f3a | 2009-02-06 11:45:46 +0000 | [diff] [blame] | 1674 | if (t->fs == p->fs) |
| 1675 | n_fs++; |
David Howells | 0bf2f3a | 2009-02-06 11:45:46 +0000 | [diff] [blame] | 1676 | } |
Oleg Nesterov | 437f7fd | 2009-04-24 01:02:45 +0200 | [diff] [blame] | 1677 | rcu_read_unlock(); |
David Howells | 0bf2f3a | 2009-02-06 11:45:46 +0000 | [diff] [blame] | 1678 | |
Kees Cook | 90383cc | 2024-01-24 11:15:33 -0800 | [diff] [blame] | 1679 | /* "users" and "in_exec" locked for copy_fs() */ |
Oleg Nesterov | 9e00cdb | 2014-01-23 15:55:50 -0800 | [diff] [blame] | 1680 | if (p->fs->users > n_fs) |
David Howells | a6f76f2 | 2008-11-14 10:39:24 +1100 | [diff] [blame] | 1681 | bprm->unsafe |= LSM_UNSAFE_SHARE; |
Oleg Nesterov | 9e00cdb | 2014-01-23 15:55:50 -0800 | [diff] [blame] | 1682 | else |
| 1683 | p->fs->in_exec = 1; |
Nick Piggin | 2a4419b | 2010-08-18 04:37:33 +1000 | [diff] [blame] | 1684 | spin_unlock(&p->fs->lock); |
David Howells | a6f76f2 | 2008-11-14 10:39:24 +1100 | [diff] [blame] | 1685 | } |
| 1686 | |
Eric W. Biederman | 56305aa | 2020-05-29 22:00:54 -0500 | [diff] [blame] | 1687 | static void bprm_fill_uid(struct linux_binprm *bprm, struct file *file) |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1688 | { |
Eric W. Biederman | 56305aa | 2020-05-29 22:00:54 -0500 | [diff] [blame] | 1689 | /* Handle suid and sgid on files */ |
Christian Brauner | e67fe63 | 2023-01-13 12:49:30 +0100 | [diff] [blame] | 1690 | struct mnt_idmap *idmap; |
Al Viro | e6ae438 | 2022-08-20 11:46:10 -0400 | [diff] [blame] | 1691 | struct inode *inode = file_inode(file); |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1692 | unsigned int mode; |
Christian Brauner | a2bd096 | 2022-06-22 22:12:16 +0200 | [diff] [blame] | 1693 | vfsuid_t vfsuid; |
| 1694 | vfsgid_t vfsgid; |
Kees Cook | f50733b | 2024-08-08 11:39:08 -0700 | [diff] [blame] | 1695 | int err; |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1696 | |
Eric W. Biederman | 56305aa | 2020-05-29 22:00:54 -0500 | [diff] [blame] | 1697 | if (!mnt_may_suid(file->f_path.mnt)) |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1698 | return; |
| 1699 | |
| 1700 | if (task_no_new_privs(current)) |
| 1701 | return; |
| 1702 | |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1703 | mode = READ_ONCE(inode->i_mode); |
| 1704 | if (!(mode & (S_ISUID|S_ISGID))) |
| 1705 | return; |
| 1706 | |
Christian Brauner | e67fe63 | 2023-01-13 12:49:30 +0100 | [diff] [blame] | 1707 | idmap = file_mnt_idmap(file); |
Christian Brauner | 1ab2996 | 2021-01-21 14:19:42 +0100 | [diff] [blame] | 1708 | |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1709 | /* Be careful if suid/sgid is set */ |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 1710 | inode_lock(inode); |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1711 | |
Kees Cook | f50733b | 2024-08-08 11:39:08 -0700 | [diff] [blame] | 1712 | /* Atomically reload and check mode/uid/gid now that lock held. */ |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1713 | mode = inode->i_mode; |
Christian Brauner | e67fe63 | 2023-01-13 12:49:30 +0100 | [diff] [blame] | 1714 | vfsuid = i_uid_into_vfsuid(idmap, inode); |
| 1715 | vfsgid = i_gid_into_vfsgid(idmap, inode); |
Kees Cook | f50733b | 2024-08-08 11:39:08 -0700 | [diff] [blame] | 1716 | err = inode_permission(idmap, inode, MAY_EXEC); |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 1717 | inode_unlock(inode); |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1718 | |
Kees Cook | f50733b | 2024-08-08 11:39:08 -0700 | [diff] [blame] | 1719 | /* Did the exec bit vanish out from under us? Give up. */ |
| 1720 | if (err) |
| 1721 | return; |
| 1722 | |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1723 | /* We ignore suid/sgid if there are no mappings for them in the ns */ |
Christian Brauner | a2bd096 | 2022-06-22 22:12:16 +0200 | [diff] [blame] | 1724 | if (!vfsuid_has_mapping(bprm->cred->user_ns, vfsuid) || |
| 1725 | !vfsgid_has_mapping(bprm->cred->user_ns, vfsgid)) |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1726 | return; |
| 1727 | |
| 1728 | if (mode & S_ISUID) { |
| 1729 | bprm->per_clear |= PER_CLEAR_ON_SETID; |
Christian Brauner | a2bd096 | 2022-06-22 22:12:16 +0200 | [diff] [blame] | 1730 | bprm->cred->euid = vfsuid_into_kuid(vfsuid); |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1731 | } |
| 1732 | |
| 1733 | if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) { |
| 1734 | bprm->per_clear |= PER_CLEAR_ON_SETID; |
Christian Brauner | a2bd096 | 2022-06-22 22:12:16 +0200 | [diff] [blame] | 1735 | bprm->cred->egid = vfsgid_into_kgid(vfsgid); |
Jann Horn | 8b01fc8 | 2015-04-19 02:48:39 +0200 | [diff] [blame] | 1736 | } |
| 1737 | } |
| 1738 | |
Oleg Nesterov | 9e00cdb | 2014-01-23 15:55:50 -0800 | [diff] [blame] | 1739 | /* |
Eric W. Biederman | 56305aa | 2020-05-29 22:00:54 -0500 | [diff] [blame] | 1740 | * Compute brpm->cred based upon the final binary. |
| 1741 | */ |
| 1742 | static int bprm_creds_from_file(struct linux_binprm *bprm) |
| 1743 | { |
| 1744 | /* Compute creds based on which file? */ |
| 1745 | struct file *file = bprm->execfd_creds ? bprm->executable : bprm->file; |
| 1746 | |
| 1747 | bprm_fill_uid(bprm, file); |
| 1748 | return security_bprm_creds_from_file(bprm, file); |
| 1749 | } |
| 1750 | |
| 1751 | /* |
Oleg Nesterov | 9e00cdb | 2014-01-23 15:55:50 -0800 | [diff] [blame] | 1752 | * Fill the binprm structure from the inode. |
Eric W. Biederman | 56305aa | 2020-05-29 22:00:54 -0500 | [diff] [blame] | 1753 | * Read the first BINPRM_BUF_SIZE bytes |
David Howells | a6f76f2 | 2008-11-14 10:39:24 +1100 | [diff] [blame] | 1754 | * |
| 1755 | * This may be called multiple times for binary chains (scripts for example). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1756 | */ |
Eric W. Biederman | 8b72ca9 | 2020-05-13 22:25:20 -0500 | [diff] [blame] | 1757 | static int prepare_binprm(struct linux_binprm *bprm) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1758 | { |
Christoph Hellwig | bdd1d2d | 2017-09-01 17:39:13 +0200 | [diff] [blame] | 1759 | loff_t pos = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1760 | |
David Howells | a6f76f2 | 2008-11-14 10:39:24 +1100 | [diff] [blame] | 1761 | memset(bprm->buf, 0, BINPRM_BUF_SIZE); |
Christoph Hellwig | bdd1d2d | 2017-09-01 17:39:13 +0200 | [diff] [blame] | 1762 | return kernel_read(bprm->file, bprm->buf, BINPRM_BUF_SIZE, &pos); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1763 | } |
| 1764 | |
Nick Piggin | 4fc75ff | 2007-05-08 00:25:16 -0700 | [diff] [blame] | 1765 | /* |
| 1766 | * Arguments are '\0' separated strings found at the location bprm->p |
| 1767 | * points to; chop off the first by relocating brpm->p to right after |
| 1768 | * the first '\0' encountered. |
| 1769 | */ |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 1770 | int remove_arg_zero(struct linux_binprm *bprm) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1771 | { |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 1772 | unsigned long offset; |
| 1773 | char *kaddr; |
| 1774 | struct page *page; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1775 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 1776 | if (!bprm->argc) |
| 1777 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1778 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 1779 | do { |
| 1780 | offset = bprm->p & ~PAGE_MASK; |
| 1781 | page = get_arg_page(bprm, bprm->p, 0); |
Kees Cook | 725d502 | 2024-03-09 13:46:30 -0800 | [diff] [blame] | 1782 | if (!page) |
| 1783 | return -EFAULT; |
Fabio M. De Francesco | 3a608cf | 2022-08-03 20:28:56 +0200 | [diff] [blame] | 1784 | kaddr = kmap_local_page(page); |
Nick Piggin | 4fc75ff | 2007-05-08 00:25:16 -0700 | [diff] [blame] | 1785 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 1786 | for (; offset < PAGE_SIZE && kaddr[offset]; |
| 1787 | offset++, bprm->p++) |
| 1788 | ; |
Nick Piggin | 4fc75ff | 2007-05-08 00:25:16 -0700 | [diff] [blame] | 1789 | |
Fabio M. De Francesco | 3a608cf | 2022-08-03 20:28:56 +0200 | [diff] [blame] | 1790 | kunmap_local(kaddr); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 1791 | put_arg_page(page); |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 1792 | } while (offset == PAGE_SIZE); |
Nick Piggin | 4fc75ff | 2007-05-08 00:25:16 -0700 | [diff] [blame] | 1793 | |
Ollie Wild | b6a2fea | 2007-07-19 01:48:16 -0700 | [diff] [blame] | 1794 | bprm->p++; |
| 1795 | bprm->argc--; |
Nick Piggin | 4fc75ff | 2007-05-08 00:25:16 -0700 | [diff] [blame] | 1796 | |
Kees Cook | 725d502 | 2024-03-09 13:46:30 -0800 | [diff] [blame] | 1797 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1798 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1799 | EXPORT_SYMBOL(remove_arg_zero); |
| 1800 | |
Oleg Nesterov | cb7b6b1 | 2013-09-11 14:24:44 -0700 | [diff] [blame] | 1801 | #define printable(c) (((c)=='\t') || ((c)=='\n') || (0x20<=(c) && (c)<=0x7e)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1802 | /* |
| 1803 | * cycle the list of binary formats handler, until one recognizes the image |
| 1804 | */ |
Eric W. Biederman | bc2bf33 | 2020-05-18 18:43:20 -0500 | [diff] [blame] | 1805 | static int search_binary_handler(struct linux_binprm *bprm) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1806 | { |
Oleg Nesterov | cb7b6b1 | 2013-09-11 14:24:44 -0700 | [diff] [blame] | 1807 | bool need_retry = IS_ENABLED(CONFIG_MODULES); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1808 | struct linux_binfmt *fmt; |
Oleg Nesterov | cb7b6b1 | 2013-09-11 14:24:44 -0700 | [diff] [blame] | 1809 | int retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1810 | |
Eric W. Biederman | 8b72ca9 | 2020-05-13 22:25:20 -0500 | [diff] [blame] | 1811 | retval = prepare_binprm(bprm); |
| 1812 | if (retval < 0) |
| 1813 | return retval; |
Kees Cook | d740269 | 2012-12-17 16:03:20 -0800 | [diff] [blame] | 1814 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1815 | retval = security_bprm_check(bprm); |
| 1816 | if (retval) |
| 1817 | return retval; |
| 1818 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1819 | retval = -ENOENT; |
Oleg Nesterov | cb7b6b1 | 2013-09-11 14:24:44 -0700 | [diff] [blame] | 1820 | retry: |
| 1821 | read_lock(&binfmt_lock); |
| 1822 | list_for_each_entry(fmt, &formats, lh) { |
| 1823 | if (!try_module_get(fmt->module)) |
| 1824 | continue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1825 | read_unlock(&binfmt_lock); |
Alexey Dobriyan | d53ddd0 | 2019-05-14 15:44:37 -0700 | [diff] [blame] | 1826 | |
Oleg Nesterov | cb7b6b1 | 2013-09-11 14:24:44 -0700 | [diff] [blame] | 1827 | retval = fmt->load_binary(bprm); |
Alexey Dobriyan | d53ddd0 | 2019-05-14 15:44:37 -0700 | [diff] [blame] | 1828 | |
Oleg Nesterov | cb7b6b1 | 2013-09-11 14:24:44 -0700 | [diff] [blame] | 1829 | read_lock(&binfmt_lock); |
| 1830 | put_binfmt(fmt); |
Eric W. Biederman | bc2bf33 | 2020-05-18 18:43:20 -0500 | [diff] [blame] | 1831 | if (bprm->point_of_no_return || (retval != -ENOEXEC)) { |
Al Viro | 19d860a | 2014-05-04 20:11:36 -0400 | [diff] [blame] | 1832 | read_unlock(&binfmt_lock); |
| 1833 | return retval; |
| 1834 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1835 | } |
Oleg Nesterov | cb7b6b1 | 2013-09-11 14:24:44 -0700 | [diff] [blame] | 1836 | read_unlock(&binfmt_lock); |
| 1837 | |
Al Viro | 19d860a | 2014-05-04 20:11:36 -0400 | [diff] [blame] | 1838 | if (need_retry) { |
Oleg Nesterov | cb7b6b1 | 2013-09-11 14:24:44 -0700 | [diff] [blame] | 1839 | if (printable(bprm->buf[0]) && printable(bprm->buf[1]) && |
| 1840 | printable(bprm->buf[2]) && printable(bprm->buf[3])) |
| 1841 | return retval; |
Oleg Nesterov | 4e0621a | 2013-09-11 14:24:45 -0700 | [diff] [blame] | 1842 | if (request_module("binfmt-%04x", *(ushort *)(bprm->buf + 2)) < 0) |
| 1843 | return retval; |
Oleg Nesterov | cb7b6b1 | 2013-09-11 14:24:44 -0700 | [diff] [blame] | 1844 | need_retry = false; |
| 1845 | goto retry; |
| 1846 | } |
| 1847 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1848 | return retval; |
| 1849 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1850 | |
Kees Cook | 275498a | 2022-10-18 00:17:24 -0700 | [diff] [blame] | 1851 | /* binfmt handlers will call back into begin_new_exec() on success. */ |
Oleg Nesterov | 5d1baf3 | 2013-09-11 14:24:38 -0700 | [diff] [blame] | 1852 | static int exec_binprm(struct linux_binprm *bprm) |
| 1853 | { |
| 1854 | pid_t old_pid, old_vpid; |
Eric W. Biederman | bc2bf33 | 2020-05-18 18:43:20 -0500 | [diff] [blame] | 1855 | int ret, depth; |
Oleg Nesterov | 5d1baf3 | 2013-09-11 14:24:38 -0700 | [diff] [blame] | 1856 | |
| 1857 | /* Need to fetch pid before load_binary changes it */ |
| 1858 | old_pid = current->pid; |
| 1859 | rcu_read_lock(); |
| 1860 | old_vpid = task_pid_nr_ns(current, task_active_pid_ns(current->parent)); |
| 1861 | rcu_read_unlock(); |
| 1862 | |
Eric W. Biederman | bc2bf33 | 2020-05-18 18:43:20 -0500 | [diff] [blame] | 1863 | /* This allows 4 levels of binfmt rewrites before failing hard. */ |
| 1864 | for (depth = 0;; depth++) { |
| 1865 | struct file *exec; |
| 1866 | if (depth > 5) |
| 1867 | return -ELOOP; |
| 1868 | |
| 1869 | ret = search_binary_handler(bprm); |
| 1870 | if (ret < 0) |
| 1871 | return ret; |
| 1872 | if (!bprm->interpreter) |
| 1873 | break; |
| 1874 | |
| 1875 | exec = bprm->file; |
| 1876 | bprm->file = bprm->interpreter; |
| 1877 | bprm->interpreter = NULL; |
| 1878 | |
Eric W. Biederman | bc2bf33 | 2020-05-18 18:43:20 -0500 | [diff] [blame] | 1879 | if (unlikely(bprm->have_execfd)) { |
| 1880 | if (bprm->executable) { |
| 1881 | fput(exec); |
| 1882 | return -ENOEXEC; |
| 1883 | } |
| 1884 | bprm->executable = exec; |
| 1885 | } else |
| 1886 | fput(exec); |
Oleg Nesterov | 5d1baf3 | 2013-09-11 14:24:38 -0700 | [diff] [blame] | 1887 | } |
| 1888 | |
Eric W. Biederman | bc2bf33 | 2020-05-18 18:43:20 -0500 | [diff] [blame] | 1889 | audit_bprm(bprm); |
| 1890 | trace_sched_process_exec(current, old_pid, bprm); |
| 1891 | ptrace_event(PTRACE_EVENT_EXEC, old_vpid); |
| 1892 | proc_exec_connector(current); |
| 1893 | return 0; |
Oleg Nesterov | 5d1baf3 | 2013-09-11 14:24:38 -0700 | [diff] [blame] | 1894 | } |
| 1895 | |
Linus Torvalds | 978ffcb | 2024-01-08 16:43:04 -0800 | [diff] [blame] | 1896 | static int bprm_execve(struct linux_binprm *bprm) |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1897 | { |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1898 | int retval; |
| 1899 | |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1900 | retval = prepare_bprm_creds(bprm); |
| 1901 | if (retval) |
Eric W. Biederman | b604350 | 2020-11-20 17:14:18 -0600 | [diff] [blame] | 1902 | return retval; |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1903 | |
Kees Cook | 275498a | 2022-10-18 00:17:24 -0700 | [diff] [blame] | 1904 | /* |
| 1905 | * Check for unsafe execution states before exec_binprm(), which |
| 1906 | * will call back into begin_new_exec(), into bprm_creds_from_file(), |
| 1907 | * where setuid-ness is evaluated. |
| 1908 | */ |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1909 | check_unsafe_exec(bprm); |
| 1910 | current->in_execve = 1; |
Mathieu Desnoyers | af7f588 | 2022-11-22 15:39:09 -0500 | [diff] [blame] | 1911 | sched_mm_cid_before_execve(current); |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1912 | |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1913 | sched_exec(); |
| 1914 | |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1915 | /* Set the unchanging part of bprm->cred */ |
| 1916 | retval = security_bprm_creds_for_exec(bprm); |
| 1917 | if (retval) |
| 1918 | goto out; |
| 1919 | |
| 1920 | retval = exec_binprm(bprm); |
| 1921 | if (retval < 0) |
| 1922 | goto out; |
| 1923 | |
Mathieu Desnoyers | af7f588 | 2022-11-22 15:39:09 -0500 | [diff] [blame] | 1924 | sched_mm_cid_after_execve(current); |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1925 | /* execve succeeded */ |
| 1926 | current->fs->in_exec = 0; |
| 1927 | current->in_execve = 0; |
| 1928 | rseq_execve(current); |
Beau Belgrave | fd59351 | 2023-03-28 16:52:09 -0700 | [diff] [blame] | 1929 | user_events_execve(current); |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1930 | acct_update_integrals(current); |
| 1931 | task_numa_free(current, false); |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1932 | return retval; |
| 1933 | |
| 1934 | out: |
| 1935 | /* |
Randy Dunlap | 3d742d4 | 2021-02-24 12:00:48 -0800 | [diff] [blame] | 1936 | * If past the point of no return ensure the code never |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1937 | * returns to the userspace process. Use an existing fatal |
| 1938 | * signal if present otherwise terminate the process with |
| 1939 | * SIGSEGV. |
| 1940 | */ |
| 1941 | if (bprm->point_of_no_return && !fatal_signal_pending(current)) |
Eric W. Biederman | e21294a | 2021-10-25 10:50:57 -0500 | [diff] [blame] | 1942 | force_fatal_sig(SIGSEGV); |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1943 | |
Mathieu Desnoyers | af7f588 | 2022-11-22 15:39:09 -0500 | [diff] [blame] | 1944 | sched_mm_cid_after_execve(current); |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1945 | current->fs->in_exec = 0; |
| 1946 | current->in_execve = 0; |
| 1947 | |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1948 | return retval; |
| 1949 | } |
| 1950 | |
Eric W. Biederman | 25cf336 | 2020-06-25 13:56:40 -0500 | [diff] [blame] | 1951 | static int do_execveat_common(int fd, struct filename *filename, |
| 1952 | struct user_arg_ptr argv, |
| 1953 | struct user_arg_ptr envp, |
| 1954 | int flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1955 | { |
| 1956 | struct linux_binprm *bprm; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1957 | int retval; |
Vasiliy Kulikov | 72fa599 | 2011-08-08 19:02:04 +0400 | [diff] [blame] | 1958 | |
Linus Torvalds | c4ad8f9 | 2014-02-05 12:54:53 -0800 | [diff] [blame] | 1959 | if (IS_ERR(filename)) |
| 1960 | return PTR_ERR(filename); |
| 1961 | |
Vasiliy Kulikov | 72fa599 | 2011-08-08 19:02:04 +0400 | [diff] [blame] | 1962 | /* |
| 1963 | * We move the actual failure in case of RLIMIT_NPROC excess from |
| 1964 | * set*uid() to execve() because too many poorly written programs |
| 1965 | * don't check setuid() return code. Here we additionally recheck |
| 1966 | * whether NPROC limit is still exceeded. |
| 1967 | */ |
| 1968 | if ((current->flags & PF_NPROC_EXCEEDED) && |
Alexey Gladkov | de39923 | 2022-05-18 19:17:30 +0200 | [diff] [blame] | 1969 | is_rlimit_overlimit(current_ucounts(), UCOUNT_RLIMIT_NPROC, rlimit(RLIMIT_NPROC))) { |
Vasiliy Kulikov | 72fa599 | 2011-08-08 19:02:04 +0400 | [diff] [blame] | 1970 | retval = -EAGAIN; |
| 1971 | goto out_ret; |
| 1972 | } |
| 1973 | |
| 1974 | /* We're below the limit (still or again), so we don't want to make |
| 1975 | * further execve() calls fail. */ |
| 1976 | current->flags &= ~PF_NPROC_EXCEEDED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1977 | |
Linus Torvalds | 978ffcb | 2024-01-08 16:43:04 -0800 | [diff] [blame] | 1978 | bprm = alloc_bprm(fd, filename, flags); |
Eric W. Biederman | 0a8f36e | 2020-07-10 15:39:45 -0500 | [diff] [blame] | 1979 | if (IS_ERR(bprm)) { |
| 1980 | retval = PTR_ERR(bprm); |
| 1981 | goto out_ret; |
| 1982 | } |
| 1983 | |
Eric W. Biederman | d8b9cd5 | 2020-07-12 08:23:54 -0500 | [diff] [blame] | 1984 | retval = count(argv, MAX_ARG_STRINGS); |
Kees Cook | dcd46d8 | 2022-01-31 16:09:47 -0800 | [diff] [blame] | 1985 | if (retval == 0) |
| 1986 | pr_warn_once("process '%s' launched '%s' with NULL argv: empty string added\n", |
| 1987 | current->comm, bprm->filename); |
Eric W. Biederman | d8b9cd5 | 2020-07-12 08:23:54 -0500 | [diff] [blame] | 1988 | if (retval < 0) |
| 1989 | goto out_free; |
| 1990 | bprm->argc = retval; |
| 1991 | |
| 1992 | retval = count(envp, MAX_ARG_STRINGS); |
| 1993 | if (retval < 0) |
| 1994 | goto out_free; |
| 1995 | bprm->envc = retval; |
| 1996 | |
| 1997 | retval = bprm_stack_limits(bprm); |
Oleg Nesterov | 655c16a | 2019-01-03 15:28:11 -0800 | [diff] [blame] | 1998 | if (retval < 0) |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 1999 | goto out_free; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2000 | |
Christoph Hellwig | 986db2d | 2020-06-04 16:51:14 -0700 | [diff] [blame] | 2001 | retval = copy_string_kernel(bprm->filename, bprm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2002 | if (retval < 0) |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 2003 | goto out_free; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2004 | bprm->exec = bprm->p; |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 2005 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2006 | retval = copy_strings(bprm->envc, envp, bprm); |
| 2007 | if (retval < 0) |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 2008 | goto out_free; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2009 | |
| 2010 | retval = copy_strings(bprm->argc, argv, bprm); |
| 2011 | if (retval < 0) |
Eric W. Biederman | 0c9cdff | 2020-07-12 07:17:50 -0500 | [diff] [blame] | 2012 | goto out_free; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2013 | |
Kees Cook | dcd46d8 | 2022-01-31 16:09:47 -0800 | [diff] [blame] | 2014 | /* |
| 2015 | * When argv is empty, add an empty string ("") as argv[0] to |
| 2016 | * ensure confused userspace programs that start processing |
| 2017 | * from argv[1] won't end up walking envp. See also |
| 2018 | * bprm_stack_limits(). |
| 2019 | */ |
| 2020 | if (bprm->argc == 0) { |
| 2021 | retval = copy_string_kernel("", bprm); |
| 2022 | if (retval < 0) |
| 2023 | goto out_free; |
| 2024 | bprm->argc = 1; |
| 2025 | } |
| 2026 | |
Linus Torvalds | 978ffcb | 2024-01-08 16:43:04 -0800 | [diff] [blame] | 2027 | retval = bprm_execve(bprm); |
David Howells | a6f76f2 | 2008-11-14 10:39:24 +1100 | [diff] [blame] | 2028 | out_free: |
Al Viro | 08a6fac | 2008-05-10 16:38:25 -0400 | [diff] [blame] | 2029 | free_bprm(bprm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2030 | |
| 2031 | out_ret: |
Eric W. Biederman | 25cf336 | 2020-06-25 13:56:40 -0500 | [diff] [blame] | 2032 | putname(filename); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2033 | return retval; |
| 2034 | } |
| 2035 | |
Eric W. Biederman | be619f7 | 2020-07-13 12:06:48 -0500 | [diff] [blame] | 2036 | int kernel_execve(const char *kernel_filename, |
| 2037 | const char *const *argv, const char *const *envp) |
| 2038 | { |
| 2039 | struct filename *filename; |
| 2040 | struct linux_binprm *bprm; |
| 2041 | int fd = AT_FDCWD; |
| 2042 | int retval; |
| 2043 | |
Eric W. Biederman | 1b2552c | 2022-04-11 14:15:54 -0500 | [diff] [blame] | 2044 | /* It is non-sense for kernel threads to call execve */ |
| 2045 | if (WARN_ON_ONCE(current->flags & PF_KTHREAD)) |
Eric W. Biederman | 343f4c4 | 2022-04-11 11:40:14 -0500 | [diff] [blame] | 2046 | return -EINVAL; |
| 2047 | |
Eric W. Biederman | be619f7 | 2020-07-13 12:06:48 -0500 | [diff] [blame] | 2048 | filename = getname_kernel(kernel_filename); |
| 2049 | if (IS_ERR(filename)) |
| 2050 | return PTR_ERR(filename); |
| 2051 | |
Linus Torvalds | 978ffcb | 2024-01-08 16:43:04 -0800 | [diff] [blame] | 2052 | bprm = alloc_bprm(fd, filename, 0); |
Eric W. Biederman | be619f7 | 2020-07-13 12:06:48 -0500 | [diff] [blame] | 2053 | if (IS_ERR(bprm)) { |
| 2054 | retval = PTR_ERR(bprm); |
| 2055 | goto out_ret; |
| 2056 | } |
| 2057 | |
| 2058 | retval = count_strings_kernel(argv); |
Kees Cook | dcd46d8 | 2022-01-31 16:09:47 -0800 | [diff] [blame] | 2059 | if (WARN_ON_ONCE(retval == 0)) |
| 2060 | retval = -EINVAL; |
Eric W. Biederman | be619f7 | 2020-07-13 12:06:48 -0500 | [diff] [blame] | 2061 | if (retval < 0) |
| 2062 | goto out_free; |
| 2063 | bprm->argc = retval; |
| 2064 | |
| 2065 | retval = count_strings_kernel(envp); |
| 2066 | if (retval < 0) |
| 2067 | goto out_free; |
| 2068 | bprm->envc = retval; |
| 2069 | |
| 2070 | retval = bprm_stack_limits(bprm); |
| 2071 | if (retval < 0) |
| 2072 | goto out_free; |
| 2073 | |
| 2074 | retval = copy_string_kernel(bprm->filename, bprm); |
| 2075 | if (retval < 0) |
| 2076 | goto out_free; |
| 2077 | bprm->exec = bprm->p; |
| 2078 | |
| 2079 | retval = copy_strings_kernel(bprm->envc, envp, bprm); |
| 2080 | if (retval < 0) |
| 2081 | goto out_free; |
| 2082 | |
| 2083 | retval = copy_strings_kernel(bprm->argc, argv, bprm); |
| 2084 | if (retval < 0) |
| 2085 | goto out_free; |
| 2086 | |
Linus Torvalds | 978ffcb | 2024-01-08 16:43:04 -0800 | [diff] [blame] | 2087 | retval = bprm_execve(bprm); |
Eric W. Biederman | be619f7 | 2020-07-13 12:06:48 -0500 | [diff] [blame] | 2088 | out_free: |
| 2089 | free_bprm(bprm); |
| 2090 | out_ret: |
| 2091 | putname(filename); |
| 2092 | return retval; |
| 2093 | } |
| 2094 | |
| 2095 | static int do_execve(struct filename *filename, |
Oleg Nesterov | ba2d0162 | 2011-03-06 18:02:37 +0100 | [diff] [blame] | 2096 | const char __user *const __user *__argv, |
Al Viro | da3d4c5 | 2012-10-20 21:49:33 -0400 | [diff] [blame] | 2097 | const char __user *const __user *__envp) |
Oleg Nesterov | ba2d0162 | 2011-03-06 18:02:37 +0100 | [diff] [blame] | 2098 | { |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 2099 | struct user_arg_ptr argv = { .ptr.native = __argv }; |
| 2100 | struct user_arg_ptr envp = { .ptr.native = __envp }; |
David Drysdale | 51f39a1 | 2014-12-12 16:57:29 -0800 | [diff] [blame] | 2101 | return do_execveat_common(AT_FDCWD, filename, argv, envp, 0); |
| 2102 | } |
| 2103 | |
Eric W. Biederman | be619f7 | 2020-07-13 12:06:48 -0500 | [diff] [blame] | 2104 | static int do_execveat(int fd, struct filename *filename, |
David Drysdale | 51f39a1 | 2014-12-12 16:57:29 -0800 | [diff] [blame] | 2105 | const char __user *const __user *__argv, |
| 2106 | const char __user *const __user *__envp, |
| 2107 | int flags) |
| 2108 | { |
| 2109 | struct user_arg_ptr argv = { .ptr.native = __argv }; |
| 2110 | struct user_arg_ptr envp = { .ptr.native = __envp }; |
| 2111 | |
| 2112 | return do_execveat_common(fd, filename, argv, envp, flags); |
Oleg Nesterov | ba2d0162 | 2011-03-06 18:02:37 +0100 | [diff] [blame] | 2113 | } |
| 2114 | |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 2115 | #ifdef CONFIG_COMPAT |
Linus Torvalds | c4ad8f9 | 2014-02-05 12:54:53 -0800 | [diff] [blame] | 2116 | static int compat_do_execve(struct filename *filename, |
Al Viro | 38b983b | 2012-09-30 13:38:55 -0400 | [diff] [blame] | 2117 | const compat_uptr_t __user *__argv, |
Al Viro | d03d26e | 2012-10-20 21:46:25 -0400 | [diff] [blame] | 2118 | const compat_uptr_t __user *__envp) |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 2119 | { |
| 2120 | struct user_arg_ptr argv = { |
| 2121 | .is_compat = true, |
| 2122 | .ptr.compat = __argv, |
| 2123 | }; |
| 2124 | struct user_arg_ptr envp = { |
| 2125 | .is_compat = true, |
| 2126 | .ptr.compat = __envp, |
| 2127 | }; |
David Drysdale | 51f39a1 | 2014-12-12 16:57:29 -0800 | [diff] [blame] | 2128 | return do_execveat_common(AT_FDCWD, filename, argv, envp, 0); |
| 2129 | } |
| 2130 | |
| 2131 | static int compat_do_execveat(int fd, struct filename *filename, |
| 2132 | const compat_uptr_t __user *__argv, |
| 2133 | const compat_uptr_t __user *__envp, |
| 2134 | int flags) |
| 2135 | { |
| 2136 | struct user_arg_ptr argv = { |
| 2137 | .is_compat = true, |
| 2138 | .ptr.compat = __argv, |
| 2139 | }; |
| 2140 | struct user_arg_ptr envp = { |
| 2141 | .is_compat = true, |
| 2142 | .ptr.compat = __envp, |
| 2143 | }; |
| 2144 | return do_execveat_common(fd, filename, argv, envp, flags); |
Oleg Nesterov | 0e02846 | 2011-03-06 18:02:54 +0100 | [diff] [blame] | 2145 | } |
| 2146 | #endif |
| 2147 | |
Oleg Nesterov | 964ee7d | 2009-09-23 15:56:59 -0700 | [diff] [blame] | 2148 | void set_binfmt(struct linux_binfmt *new) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2149 | { |
Hiroshi Shimamoto | 801460d | 2009-09-23 15:57:41 -0700 | [diff] [blame] | 2150 | struct mm_struct *mm = current->mm; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2151 | |
Hiroshi Shimamoto | 801460d | 2009-09-23 15:57:41 -0700 | [diff] [blame] | 2152 | if (mm->binfmt) |
| 2153 | module_put(mm->binfmt->module); |
| 2154 | |
| 2155 | mm->binfmt = new; |
Oleg Nesterov | 964ee7d | 2009-09-23 15:56:59 -0700 | [diff] [blame] | 2156 | if (new) |
| 2157 | __module_get(new->module); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2158 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2159 | EXPORT_SYMBOL(set_binfmt); |
| 2160 | |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 2161 | /* |
Oleg Nesterov | 7288e11 | 2014-01-23 15:55:32 -0800 | [diff] [blame] | 2162 | * set_dumpable stores three-value SUID_DUMP_* into mm->flags. |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 2163 | */ |
| 2164 | void set_dumpable(struct mm_struct *mm, int value) |
| 2165 | { |
Oleg Nesterov | 7288e11 | 2014-01-23 15:55:32 -0800 | [diff] [blame] | 2166 | if (WARN_ON((unsigned)value > SUID_DUMP_ROOT)) |
| 2167 | return; |
| 2168 | |
Vineet Gupta | 26e1522 | 2019-03-07 16:29:23 -0800 | [diff] [blame] | 2169 | set_mask_bits(&mm->flags, MMF_DUMPABLE_MASK, value); |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 2170 | } |
Kawai, Hidehiro | 6c5d523 | 2007-07-19 01:48:27 -0700 | [diff] [blame] | 2171 | |
Al Viro | 38b983b | 2012-09-30 13:38:55 -0400 | [diff] [blame] | 2172 | SYSCALL_DEFINE3(execve, |
| 2173 | const char __user *, filename, |
| 2174 | const char __user *const __user *, argv, |
| 2175 | const char __user *const __user *, envp) |
| 2176 | { |
Linus Torvalds | c4ad8f9 | 2014-02-05 12:54:53 -0800 | [diff] [blame] | 2177 | return do_execve(getname(filename), argv, envp); |
Al Viro | 38b983b | 2012-09-30 13:38:55 -0400 | [diff] [blame] | 2178 | } |
David Drysdale | 51f39a1 | 2014-12-12 16:57:29 -0800 | [diff] [blame] | 2179 | |
| 2180 | SYSCALL_DEFINE5(execveat, |
| 2181 | int, fd, const char __user *, filename, |
| 2182 | const char __user *const __user *, argv, |
| 2183 | const char __user *const __user *, envp, |
| 2184 | int, flags) |
| 2185 | { |
David Drysdale | 51f39a1 | 2014-12-12 16:57:29 -0800 | [diff] [blame] | 2186 | return do_execveat(fd, |
Dmitry Kadashev | 8228e2c | 2021-07-08 13:34:42 +0700 | [diff] [blame] | 2187 | getname_uflags(filename, flags), |
David Drysdale | 51f39a1 | 2014-12-12 16:57:29 -0800 | [diff] [blame] | 2188 | argv, envp, flags); |
| 2189 | } |
| 2190 | |
Al Viro | 38b983b | 2012-09-30 13:38:55 -0400 | [diff] [blame] | 2191 | #ifdef CONFIG_COMPAT |
Heiko Carstens | 625b1d7 | 2014-03-04 10:53:50 +0100 | [diff] [blame] | 2192 | COMPAT_SYSCALL_DEFINE3(execve, const char __user *, filename, |
| 2193 | const compat_uptr_t __user *, argv, |
| 2194 | const compat_uptr_t __user *, envp) |
Al Viro | 38b983b | 2012-09-30 13:38:55 -0400 | [diff] [blame] | 2195 | { |
Linus Torvalds | c4ad8f9 | 2014-02-05 12:54:53 -0800 | [diff] [blame] | 2196 | return compat_do_execve(getname(filename), argv, envp); |
Al Viro | 38b983b | 2012-09-30 13:38:55 -0400 | [diff] [blame] | 2197 | } |
David Drysdale | 51f39a1 | 2014-12-12 16:57:29 -0800 | [diff] [blame] | 2198 | |
| 2199 | COMPAT_SYSCALL_DEFINE5(execveat, int, fd, |
| 2200 | const char __user *, filename, |
| 2201 | const compat_uptr_t __user *, argv, |
| 2202 | const compat_uptr_t __user *, envp, |
| 2203 | int, flags) |
| 2204 | { |
David Drysdale | 51f39a1 | 2014-12-12 16:57:29 -0800 | [diff] [blame] | 2205 | return compat_do_execveat(fd, |
Dmitry Kadashev | 8228e2c | 2021-07-08 13:34:42 +0700 | [diff] [blame] | 2206 | getname_uflags(filename, flags), |
David Drysdale | 51f39a1 | 2014-12-12 16:57:29 -0800 | [diff] [blame] | 2207 | argv, envp, flags); |
| 2208 | } |
Al Viro | 38b983b | 2012-09-30 13:38:55 -0400 | [diff] [blame] | 2209 | #endif |
Luis Chamberlain | 66ad398 | 2022-01-21 22:13:17 -0800 | [diff] [blame] | 2210 | |
| 2211 | #ifdef CONFIG_SYSCTL |
| 2212 | |
Joel Granados | 78eb4ea | 2024-07-24 20:59:29 +0200 | [diff] [blame] | 2213 | static int proc_dointvec_minmax_coredump(const struct ctl_table *table, int write, |
Luis Chamberlain | 66ad398 | 2022-01-21 22:13:17 -0800 | [diff] [blame] | 2214 | void *buffer, size_t *lenp, loff_t *ppos) |
| 2215 | { |
| 2216 | int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
| 2217 | |
| 2218 | if (!error) |
| 2219 | validate_coredump_safety(); |
| 2220 | return error; |
| 2221 | } |
| 2222 | |
| 2223 | static struct ctl_table fs_exec_sysctls[] = { |
| 2224 | { |
| 2225 | .procname = "suid_dumpable", |
| 2226 | .data = &suid_dumpable, |
| 2227 | .maxlen = sizeof(int), |
| 2228 | .mode = 0644, |
| 2229 | .proc_handler = proc_dointvec_minmax_coredump, |
| 2230 | .extra1 = SYSCTL_ZERO, |
| 2231 | .extra2 = SYSCTL_TWO, |
| 2232 | }, |
Luis Chamberlain | 66ad398 | 2022-01-21 22:13:17 -0800 | [diff] [blame] | 2233 | }; |
| 2234 | |
Luis Chamberlain | 66ad398 | 2022-01-21 22:13:17 -0800 | [diff] [blame] | 2235 | static int __init init_fs_exec_sysctls(void) |
| 2236 | { |
| 2237 | register_sysctl_init("fs", fs_exec_sysctls); |
Luis Chamberlain | 66ad398 | 2022-01-21 22:13:17 -0800 | [diff] [blame] | 2238 | return 0; |
| 2239 | } |
| 2240 | |
| 2241 | fs_initcall(init_fs_exec_sysctls); |
| 2242 | #endif /* CONFIG_SYSCTL */ |
Kees Cook | 60371f4 | 2024-05-19 17:17:59 -0700 | [diff] [blame] | 2243 | |
| 2244 | #ifdef CONFIG_EXEC_KUNIT_TEST |
Kees Cook | b6f5ee4 | 2024-07-20 10:03:14 -0700 | [diff] [blame] | 2245 | #include "tests/exec_kunit.c" |
Kees Cook | 60371f4 | 2024-05-19 17:17:59 -0700 | [diff] [blame] | 2246 | #endif |