Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/fs/open.c |
| 3 | * |
| 4 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 5 | */ |
| 6 | |
| 7 | #include <linux/string.h> |
| 8 | #include <linux/mm.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | #include <linux/file.h> |
Al Viro | 9f3acc3 | 2008-04-24 07:44:08 -0400 | [diff] [blame] | 10 | #include <linux/fdtable.h> |
Robert Love | 0eeca28 | 2005-07-12 17:06:03 -0400 | [diff] [blame] | 11 | #include <linux/fsnotify.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/module.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #include <linux/tty.h> |
| 14 | #include <linux/namei.h> |
| 15 | #include <linux/backing-dev.h> |
Randy Dunlap | 16f7e0f | 2006-01-11 12:17:46 -0800 | [diff] [blame] | 16 | #include <linux/capability.h> |
Andrew G. Morgan | 086f731 | 2008-07-04 09:59:58 -0700 | [diff] [blame] | 17 | #include <linux/securebits.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | #include <linux/security.h> |
| 19 | #include <linux/mount.h> |
Ulrich Drepper | 5590ff0 | 2006-01-18 17:43:53 -0800 | [diff] [blame] | 20 | #include <linux/fcntl.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 21 | #include <linux/slab.h> |
Linus Torvalds | 7c0f6ba | 2016-12-24 11:46:01 -0800 | [diff] [blame] | 22 | #include <linux/uaccess.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #include <linux/fs.h> |
Yoav Zach | ef3daed | 2005-06-23 00:09:58 -0700 | [diff] [blame] | 24 | #include <linux/personality.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | #include <linux/pagemap.h> |
| 26 | #include <linux/syscalls.h> |
Dipankar Sarma | ab2af1f | 2005-09-09 13:04:13 -0700 | [diff] [blame] | 27 | #include <linux/rcupdate.h> |
Amy Griffis | 73241cc | 2005-11-03 16:00:25 +0000 | [diff] [blame] | 28 | #include <linux/audit.h> |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 29 | #include <linux/falloc.h> |
Al Viro | 5ad4e53 | 2009-03-29 19:50:06 -0400 | [diff] [blame] | 30 | #include <linux/fs_struct.h> |
Al Viro | b65a9cf | 2009-12-16 06:27:40 -0500 | [diff] [blame] | 31 | #include <linux/ima.h> |
Eric Paris | 2dfc1ca | 2009-12-17 20:30:52 -0500 | [diff] [blame] | 32 | #include <linux/dnotify.h> |
Al Viro | 3f6d078 | 2013-02-24 13:49:08 -0500 | [diff] [blame] | 33 | #include <linux/compat.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | |
Eric Paris | e81e3f4 | 2009-12-04 15:47:36 -0500 | [diff] [blame] | 35 | #include "internal.h" |
| 36 | |
NeilBrown | 4a30131 | 2006-01-08 01:02:39 -0800 | [diff] [blame] | 37 | int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs, |
| 38 | struct file *filp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | { |
Amerigo Wang | 939a942 | 2009-08-20 19:29:03 -0700 | [diff] [blame] | 40 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | struct iattr newattrs; |
| 42 | |
| 43 | /* Not pretty: "inode->i_size" shouldn't really be signed. But it is. */ |
| 44 | if (length < 0) |
| 45 | return -EINVAL; |
| 46 | |
| 47 | newattrs.ia_size = length; |
NeilBrown | 4a30131 | 2006-01-08 01:02:39 -0800 | [diff] [blame] | 48 | newattrs.ia_valid = ATTR_SIZE | time_attrs; |
Miklos Szeredi | cc4e69d | 2005-11-07 00:59:49 -0800 | [diff] [blame] | 49 | if (filp) { |
| 50 | newattrs.ia_file = filp; |
| 51 | newattrs.ia_valid |= ATTR_FILE; |
| 52 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 53 | |
Jan Kara | 45f147a | 2015-05-21 16:05:55 +0200 | [diff] [blame] | 54 | /* Remove suid, sgid, and file capabilities on truncate too */ |
| 55 | ret = dentry_needs_remove_privs(dentry); |
| 56 | if (ret < 0) |
| 57 | return ret; |
Amerigo Wang | 939a942 | 2009-08-20 19:29:03 -0700 | [diff] [blame] | 58 | if (ret) |
| 59 | newattrs.ia_valid |= ret | ATTR_FORCE; |
Linus Torvalds | 7b82dc0 | 2007-05-08 20:10:00 -0700 | [diff] [blame] | 60 | |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 61 | inode_lock(dentry->d_inode); |
J. Bruce Fields | 27ac0ff | 2011-09-20 17:19:26 -0400 | [diff] [blame] | 62 | /* Note any delegations or leases have already been broken: */ |
| 63 | ret = notify_change(dentry, &newattrs, NULL); |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 64 | inode_unlock(dentry->d_inode); |
Amerigo Wang | 939a942 | 2009-08-20 19:29:03 -0700 | [diff] [blame] | 65 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | } |
| 67 | |
Al Viro | 7df818b | 2016-03-25 14:24:09 -0400 | [diff] [blame] | 68 | long vfs_truncate(const struct path *path, loff_t length) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 69 | { |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 70 | struct inode *inode; |
Miklos Szeredi | 4d0c5ba | 2016-09-16 12:44:21 +0200 | [diff] [blame] | 71 | struct dentry *upperdentry; |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 72 | long error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 74 | inode = path->dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | |
| 76 | /* For directories it's -EISDIR, for other non-regulars - -EINVAL */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | if (S_ISDIR(inode->i_mode)) |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 78 | return -EISDIR; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 79 | if (!S_ISREG(inode->i_mode)) |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 80 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 82 | error = mnt_want_write(path->mnt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | if (error) |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 84 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | |
Al Viro | 256984a | 2008-07-22 08:09:30 -0400 | [diff] [blame] | 86 | error = inode_permission(inode, MAY_WRITE); |
Dave Hansen | 9ac9b84 | 2008-02-15 14:37:52 -0800 | [diff] [blame] | 87 | if (error) |
| 88 | goto mnt_drop_write_and_out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | |
| 90 | error = -EPERM; |
Miklos Szeredi | c82e42d | 2008-06-24 16:50:12 +0200 | [diff] [blame] | 91 | if (IS_APPEND(inode)) |
Dave Hansen | 9ac9b84 | 2008-02-15 14:37:52 -0800 | [diff] [blame] | 92 | goto mnt_drop_write_and_out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | |
Miklos Szeredi | 4d0c5ba | 2016-09-16 12:44:21 +0200 | [diff] [blame] | 94 | /* |
| 95 | * If this is an overlayfs then do as if opening the file so we get |
| 96 | * write access on the upper inode, not on the overlay inode. For |
| 97 | * non-overlay filesystems d_real() is an identity function. |
| 98 | */ |
| 99 | upperdentry = d_real(path->dentry, NULL, O_WRONLY); |
| 100 | error = PTR_ERR(upperdentry); |
| 101 | if (IS_ERR(upperdentry)) |
| 102 | goto mnt_drop_write_and_out; |
| 103 | |
| 104 | error = get_write_access(upperdentry->d_inode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | if (error) |
Dave Hansen | 9ac9b84 | 2008-02-15 14:37:52 -0800 | [diff] [blame] | 106 | goto mnt_drop_write_and_out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | |
david m. richter | 9700382 | 2007-07-31 00:39:12 -0700 | [diff] [blame] | 108 | /* |
| 109 | * Make sure that there are no leases. get_write_access() protects |
| 110 | * against the truncate racing with a lease-granting setlease(). |
| 111 | */ |
Al Viro | 8737c93 | 2009-12-24 06:47:55 -0500 | [diff] [blame] | 112 | error = break_lease(inode, O_WRONLY); |
david m. richter | 9700382 | 2007-07-31 00:39:12 -0700 | [diff] [blame] | 113 | if (error) |
| 114 | goto put_write_and_out; |
| 115 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | error = locks_verify_truncate(inode, NULL, length); |
Kentaro Takeda | be6d3e5 | 2008-12-17 13:24:15 +0900 | [diff] [blame] | 117 | if (!error) |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 118 | error = security_path_truncate(path); |
Christoph Hellwig | 907f455 | 2010-03-03 09:05:06 -0500 | [diff] [blame] | 119 | if (!error) |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 120 | error = do_truncate(path->dentry, length, 0, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 121 | |
david m. richter | 9700382 | 2007-07-31 00:39:12 -0700 | [diff] [blame] | 122 | put_write_and_out: |
Miklos Szeredi | 4d0c5ba | 2016-09-16 12:44:21 +0200 | [diff] [blame] | 123 | put_write_access(upperdentry->d_inode); |
Dave Hansen | 9ac9b84 | 2008-02-15 14:37:52 -0800 | [diff] [blame] | 124 | mnt_drop_write_and_out: |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 125 | mnt_drop_write(path->mnt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | out: |
| 127 | return error; |
| 128 | } |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 129 | EXPORT_SYMBOL_GPL(vfs_truncate); |
| 130 | |
| 131 | static long do_sys_truncate(const char __user *pathname, loff_t length) |
| 132 | { |
Jeff Layton | 48f7530 | 2012-12-11 12:10:11 -0500 | [diff] [blame] | 133 | unsigned int lookup_flags = LOOKUP_FOLLOW; |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 134 | struct path path; |
| 135 | int error; |
| 136 | |
| 137 | if (length < 0) /* sorry, but loff_t says... */ |
| 138 | return -EINVAL; |
| 139 | |
Jeff Layton | 48f7530 | 2012-12-11 12:10:11 -0500 | [diff] [blame] | 140 | retry: |
| 141 | error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 142 | if (!error) { |
| 143 | error = vfs_truncate(&path, length); |
| 144 | path_put(&path); |
| 145 | } |
Jeff Layton | 48f7530 | 2012-12-11 12:10:11 -0500 | [diff] [blame] | 146 | if (retry_estale(error, lookup_flags)) { |
| 147 | lookup_flags |= LOOKUP_REVAL; |
| 148 | goto retry; |
| 149 | } |
David Howells | a02de96 | 2012-12-20 21:52:36 +0000 | [diff] [blame] | 150 | return error; |
| 151 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | |
Heiko Carstens | 4fd8da8 | 2009-09-23 17:49:55 +0200 | [diff] [blame] | 153 | SYSCALL_DEFINE2(truncate, const char __user *, path, long, length) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | { |
Heiko Carstens | 4fd8da8 | 2009-09-23 17:49:55 +0200 | [diff] [blame] | 155 | return do_sys_truncate(path, length); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 156 | } |
| 157 | |
Al Viro | 3f6d078 | 2013-02-24 13:49:08 -0500 | [diff] [blame] | 158 | #ifdef CONFIG_COMPAT |
| 159 | COMPAT_SYSCALL_DEFINE2(truncate, const char __user *, path, compat_off_t, length) |
| 160 | { |
| 161 | return do_sys_truncate(path, length); |
| 162 | } |
| 163 | #endif |
| 164 | |
Matt Mackall | b01ec0e | 2006-01-08 01:05:20 -0800 | [diff] [blame] | 165 | static long do_sys_ftruncate(unsigned int fd, loff_t length, int small) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | { |
Al Viro | bf2965d | 2012-08-26 20:13:36 -0400 | [diff] [blame] | 167 | struct inode *inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | struct dentry *dentry; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 169 | struct fd f; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 170 | int error; |
| 171 | |
| 172 | error = -EINVAL; |
| 173 | if (length < 0) |
| 174 | goto out; |
| 175 | error = -EBADF; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 176 | f = fdget(fd); |
| 177 | if (!f.file) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | goto out; |
| 179 | |
| 180 | /* explicitly opened as large or we are on 64-bit box */ |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 181 | if (f.file->f_flags & O_LARGEFILE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | small = 0; |
| 183 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 184 | dentry = f.file->f_path.dentry; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | inode = dentry->d_inode; |
| 186 | error = -EINVAL; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 187 | if (!S_ISREG(inode->i_mode) || !(f.file->f_mode & FMODE_WRITE)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 188 | goto out_putf; |
| 189 | |
| 190 | error = -EINVAL; |
| 191 | /* Cannot ftruncate over 2^31 bytes without large file support */ |
| 192 | if (small && length > MAX_NON_LFS) |
| 193 | goto out_putf; |
| 194 | |
| 195 | error = -EPERM; |
| 196 | if (IS_APPEND(inode)) |
| 197 | goto out_putf; |
| 198 | |
Jan Kara | 14da920 | 2012-06-12 16:20:37 +0200 | [diff] [blame] | 199 | sb_start_write(inode->i_sb); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 200 | error = locks_verify_truncate(inode, f.file, length); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 201 | if (!error) |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 202 | error = security_path_truncate(&f.file->f_path); |
Kentaro Takeda | be6d3e5 | 2008-12-17 13:24:15 +0900 | [diff] [blame] | 203 | if (!error) |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 204 | error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, f.file); |
Jan Kara | 14da920 | 2012-06-12 16:20:37 +0200 | [diff] [blame] | 205 | sb_end_write(inode->i_sb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | out_putf: |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 207 | fdput(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | out: |
| 209 | return error; |
| 210 | } |
| 211 | |
Heiko Carstens | bdc480e | 2009-01-14 14:14:12 +0100 | [diff] [blame] | 212 | SYSCALL_DEFINE2(ftruncate, unsigned int, fd, unsigned long, length) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | { |
Al Viro | 2cf0966 | 2013-01-21 15:25:54 -0500 | [diff] [blame] | 214 | return do_sys_ftruncate(fd, length, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 215 | } |
| 216 | |
Al Viro | 3f6d078 | 2013-02-24 13:49:08 -0500 | [diff] [blame] | 217 | #ifdef CONFIG_COMPAT |
| 218 | COMPAT_SYSCALL_DEFINE2(ftruncate, unsigned int, fd, compat_ulong_t, length) |
| 219 | { |
| 220 | return do_sys_ftruncate(fd, length, 1); |
| 221 | } |
| 222 | #endif |
| 223 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 224 | /* LFS versions of truncate are only needed on 32 bit machines */ |
| 225 | #if BITS_PER_LONG == 32 |
Al Viro | 4a0fd5b | 2013-01-21 15:16:58 -0500 | [diff] [blame] | 226 | SYSCALL_DEFINE2(truncate64, const char __user *, path, loff_t, length) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 227 | { |
| 228 | return do_sys_truncate(path, length); |
| 229 | } |
| 230 | |
Al Viro | 4a0fd5b | 2013-01-21 15:16:58 -0500 | [diff] [blame] | 231 | SYSCALL_DEFINE2(ftruncate64, unsigned int, fd, loff_t, length) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 232 | { |
Al Viro | 2cf0966 | 2013-01-21 15:25:54 -0500 | [diff] [blame] | 233 | return do_sys_ftruncate(fd, length, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | } |
Heiko Carstens | 6673e0c | 2009-01-14 14:14:02 +0100 | [diff] [blame] | 235 | #endif /* BITS_PER_LONG == 32 */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 236 | |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 237 | |
Anna Schumaker | 72c72bd | 2014-11-07 14:44:25 -0500 | [diff] [blame] | 238 | int vfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len) |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 239 | { |
Al Viro | 496ad9a | 2013-01-23 17:07:38 -0500 | [diff] [blame] | 240 | struct inode *inode = file_inode(file); |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 241 | long ret; |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 242 | |
| 243 | if (offset < 0 || len <= 0) |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 244 | return -EINVAL; |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 245 | |
| 246 | /* Return error if mode is not supported */ |
Namjae Jeon | dd46c78 | 2015-03-25 15:07:05 +1100 | [diff] [blame] | 247 | if (mode & ~FALLOC_FL_SUPPORTED_MASK) |
Lukas Czerner | 409332b | 2014-03-13 19:07:42 +1100 | [diff] [blame] | 248 | return -EOPNOTSUPP; |
| 249 | |
| 250 | /* Punch hole and zero range are mutually exclusive */ |
| 251 | if ((mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_ZERO_RANGE)) == |
| 252 | (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_ZERO_RANGE)) |
Josef Bacik | 79124f18 | 2010-11-17 20:46:15 -0500 | [diff] [blame] | 253 | return -EOPNOTSUPP; |
| 254 | |
| 255 | /* Punch hole must have keep size set */ |
| 256 | if ((mode & FALLOC_FL_PUNCH_HOLE) && |
| 257 | !(mode & FALLOC_FL_KEEP_SIZE)) |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 258 | return -EOPNOTSUPP; |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 259 | |
Namjae Jeon | 00f5e61 | 2014-02-24 10:58:15 +1100 | [diff] [blame] | 260 | /* Collapse range should only be used exclusively. */ |
| 261 | if ((mode & FALLOC_FL_COLLAPSE_RANGE) && |
| 262 | (mode & ~FALLOC_FL_COLLAPSE_RANGE)) |
| 263 | return -EINVAL; |
| 264 | |
Namjae Jeon | dd46c78 | 2015-03-25 15:07:05 +1100 | [diff] [blame] | 265 | /* Insert range should only be used exclusively. */ |
| 266 | if ((mode & FALLOC_FL_INSERT_RANGE) && |
| 267 | (mode & ~FALLOC_FL_INSERT_RANGE)) |
| 268 | return -EINVAL; |
| 269 | |
Darrick J. Wong | 71be6b4 | 2016-10-03 09:11:14 -0700 | [diff] [blame] | 270 | /* Unshare range should only be used with allocate mode. */ |
| 271 | if ((mode & FALLOC_FL_UNSHARE_RANGE) && |
| 272 | (mode & ~(FALLOC_FL_UNSHARE_RANGE | FALLOC_FL_KEEP_SIZE))) |
| 273 | return -EINVAL; |
| 274 | |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 275 | if (!(file->f_mode & FMODE_WRITE)) |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 276 | return -EBADF; |
Marco Stornelli | 1ca551c | 2011-03-05 11:10:19 +0100 | [diff] [blame] | 277 | |
Namjae Jeon | 00f5e61 | 2014-02-24 10:58:15 +1100 | [diff] [blame] | 278 | /* |
Lukas Czerner | 8fc61d9 | 2014-04-12 09:51:34 -0400 | [diff] [blame] | 279 | * We can only allow pure fallocate on append only files |
Namjae Jeon | 00f5e61 | 2014-02-24 10:58:15 +1100 | [diff] [blame] | 280 | */ |
Lukas Czerner | 8fc61d9 | 2014-04-12 09:51:34 -0400 | [diff] [blame] | 281 | if ((mode & ~FALLOC_FL_KEEP_SIZE) && IS_APPEND(inode)) |
Marco Stornelli | 1ca551c | 2011-03-05 11:10:19 +0100 | [diff] [blame] | 282 | return -EPERM; |
| 283 | |
| 284 | if (IS_IMMUTABLE(inode)) |
| 285 | return -EPERM; |
| 286 | |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 287 | /* |
Eric Biggers | 6d2b617 | 2014-06-24 23:45:08 -0500 | [diff] [blame] | 288 | * We cannot allow any fallocate operation on an active swapfile |
Lukas Czerner | 0790b31 | 2014-04-12 10:05:37 -0400 | [diff] [blame] | 289 | */ |
| 290 | if (IS_SWAPFILE(inode)) |
Eric Biggers | 6d2b617 | 2014-06-24 23:45:08 -0500 | [diff] [blame] | 291 | return -ETXTBSY; |
Lukas Czerner | 0790b31 | 2014-04-12 10:05:37 -0400 | [diff] [blame] | 292 | |
| 293 | /* |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 294 | * Revalidate the write permissions, in case security policy has |
| 295 | * changed since the files were opened. |
| 296 | */ |
| 297 | ret = security_file_permission(file, MAY_WRITE); |
| 298 | if (ret) |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 299 | return ret; |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 300 | |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 301 | if (S_ISFIFO(inode->i_mode)) |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 302 | return -ESPIPE; |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 303 | |
Amir Goldstein | 9e79b13 | 2017-01-31 10:34:55 +0200 | [diff] [blame] | 304 | if (S_ISDIR(inode->i_mode)) |
| 305 | return -EISDIR; |
| 306 | |
| 307 | if (!S_ISREG(inode->i_mode) && !S_ISBLK(inode->i_mode)) |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 308 | return -ENODEV; |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 309 | |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 310 | /* Check for wrap through zero too */ |
| 311 | if (((offset + len) > inode->i_sb->s_maxbytes) || ((offset + len) < 0)) |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 312 | return -EFBIG; |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 313 | |
Christoph Hellwig | 2fe17c1 | 2011-01-14 13:07:43 +0100 | [diff] [blame] | 314 | if (!file->f_op->fallocate) |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 315 | return -EOPNOTSUPP; |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 316 | |
Amir Goldstein | bfe219d | 2017-01-31 10:34:57 +0200 | [diff] [blame] | 317 | file_start_write(file); |
Jan Kara | 14da920 | 2012-06-12 16:20:37 +0200 | [diff] [blame] | 318 | ret = file->f_op->fallocate(file, mode, offset, len); |
Heinrich Schuchardt | 820c12d | 2014-12-12 16:58:34 -0800 | [diff] [blame] | 319 | |
| 320 | /* |
| 321 | * Create inotify and fanotify events. |
| 322 | * |
| 323 | * To keep the logic simple always create events if fallocate succeeds. |
| 324 | * This implies that events are even created if the file size remains |
| 325 | * unchanged, e.g. when using flag FALLOC_FL_KEEP_SIZE. |
| 326 | */ |
| 327 | if (ret == 0) |
| 328 | fsnotify_modify(file); |
| 329 | |
Amir Goldstein | bfe219d | 2017-01-31 10:34:57 +0200 | [diff] [blame] | 330 | file_end_write(file); |
Jan Kara | 14da920 | 2012-06-12 16:20:37 +0200 | [diff] [blame] | 331 | return ret; |
Amit Arora | 97ac735 | 2007-07-17 21:42:44 -0400 | [diff] [blame] | 332 | } |
Anna Schumaker | 72c72bd | 2014-11-07 14:44:25 -0500 | [diff] [blame] | 333 | EXPORT_SYMBOL_GPL(vfs_fallocate); |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 334 | |
Al Viro | 4a0fd5b | 2013-01-21 15:16:58 -0500 | [diff] [blame] | 335 | SYSCALL_DEFINE4(fallocate, int, fd, int, mode, loff_t, offset, loff_t, len) |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 336 | { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 337 | struct fd f = fdget(fd); |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 338 | int error = -EBADF; |
| 339 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 340 | if (f.file) { |
Anna Schumaker | 72c72bd | 2014-11-07 14:44:25 -0500 | [diff] [blame] | 341 | error = vfs_fallocate(f.file, mode, offset, len); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 342 | fdput(f); |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 343 | } |
Ankit Jain | 3e63cbb | 2009-06-19 14:28:07 -0400 | [diff] [blame] | 344 | return error; |
| 345 | } |
| 346 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 347 | /* |
| 348 | * access() needs to use the real uid/gid, not the effective uid/gid. |
| 349 | * We do this by temporarily clearing all FS-related capabilities and |
| 350 | * switching the fsuid/fsgid around to the real ones. |
| 351 | */ |
Heiko Carstens | 6559eed8 | 2009-01-14 14:14:32 +0100 | [diff] [blame] | 352 | SYSCALL_DEFINE3(faccessat, int, dfd, const char __user *, filename, int, mode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 353 | { |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 354 | const struct cred *old_cred; |
| 355 | struct cred *override_cred; |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 356 | struct path path; |
Al Viro | 256984a | 2008-07-22 08:09:30 -0400 | [diff] [blame] | 357 | struct inode *inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 358 | int res; |
Jeff Layton | 87fa559 | 2012-12-11 12:10:11 -0500 | [diff] [blame] | 359 | unsigned int lookup_flags = LOOKUP_FOLLOW; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 360 | |
| 361 | if (mode & ~S_IRWXO) /* where's F_OK, X_OK, W_OK, R_OK? */ |
| 362 | return -EINVAL; |
| 363 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 364 | override_cred = prepare_creds(); |
| 365 | if (!override_cred) |
| 366 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 367 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 368 | override_cred->fsuid = override_cred->uid; |
| 369 | override_cred->fsgid = override_cred->gid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 370 | |
Andrew G. Morgan | 086f731 | 2008-07-04 09:59:58 -0700 | [diff] [blame] | 371 | if (!issecure(SECURE_NO_SETUID_FIXUP)) { |
David Howells | 1cdcbec | 2008-11-14 10:39:14 +1100 | [diff] [blame] | 372 | /* Clear the capabilities if we switch to a non-root user */ |
Eric W. Biederman | 18815a1 | 2012-02-07 16:45:47 -0800 | [diff] [blame] | 373 | kuid_t root_uid = make_kuid(override_cred->user_ns, 0); |
| 374 | if (!uid_eq(override_cred->uid, root_uid)) |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 375 | cap_clear(override_cred->cap_effective); |
Andrew G. Morgan | 086f731 | 2008-07-04 09:59:58 -0700 | [diff] [blame] | 376 | else |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 377 | override_cred->cap_effective = |
| 378 | override_cred->cap_permitted; |
Andrew G. Morgan | 086f731 | 2008-07-04 09:59:58 -0700 | [diff] [blame] | 379 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 380 | |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 381 | old_cred = override_creds(override_cred); |
Jeff Layton | 87fa559 | 2012-12-11 12:10:11 -0500 | [diff] [blame] | 382 | retry: |
| 383 | res = user_path_at(dfd, filename, lookup_flags, &path); |
Dave Hansen | 6902d92 | 2006-09-30 23:29:01 -0700 | [diff] [blame] | 384 | if (res) |
| 385 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 386 | |
David Howells | 63afdfc | 2015-05-06 15:59:00 +0100 | [diff] [blame] | 387 | inode = d_backing_inode(path.dentry); |
Al Viro | 256984a | 2008-07-22 08:09:30 -0400 | [diff] [blame] | 388 | |
| 389 | if ((mode & MAY_EXEC) && S_ISREG(inode->i_mode)) { |
Al Viro | 3052447 | 2008-07-22 00:02:33 -0400 | [diff] [blame] | 390 | /* |
| 391 | * MAY_EXEC on regular files is denied if the fs is mounted |
| 392 | * with the "noexec" flag. |
| 393 | */ |
| 394 | res = -EACCES; |
Eric W. Biederman | 90f8572 | 2015-06-29 14:42:03 -0500 | [diff] [blame] | 395 | if (path_noexec(&path)) |
Al Viro | 3052447 | 2008-07-22 00:02:33 -0400 | [diff] [blame] | 396 | goto out_path_release; |
| 397 | } |
| 398 | |
Al Viro | 256984a | 2008-07-22 08:09:30 -0400 | [diff] [blame] | 399 | res = inode_permission(inode, mode | MAY_ACCESS); |
Dave Hansen | 6902d92 | 2006-09-30 23:29:01 -0700 | [diff] [blame] | 400 | /* SuS v2 requires we report a read only fs too */ |
Al Viro | 256984a | 2008-07-22 08:09:30 -0400 | [diff] [blame] | 401 | if (res || !(mode & S_IWOTH) || special_file(inode->i_mode)) |
Dave Hansen | 6902d92 | 2006-09-30 23:29:01 -0700 | [diff] [blame] | 402 | goto out_path_release; |
Dave Hansen | 2f676cb | 2008-02-15 14:37:55 -0800 | [diff] [blame] | 403 | /* |
| 404 | * This is a rare case where using __mnt_is_readonly() |
| 405 | * is OK without a mnt_want/drop_write() pair. Since |
| 406 | * no actual write to the fs is performed here, we do |
| 407 | * not need to telegraph to that to anyone. |
| 408 | * |
| 409 | * By doing this, we accept that this access is |
| 410 | * inherently racy and know that the fs may change |
| 411 | * state before we even see this result. |
| 412 | */ |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 413 | if (__mnt_is_readonly(path.mnt)) |
Dave Hansen | 6902d92 | 2006-09-30 23:29:01 -0700 | [diff] [blame] | 414 | res = -EROFS; |
| 415 | |
| 416 | out_path_release: |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 417 | path_put(&path); |
Jeff Layton | 87fa559 | 2012-12-11 12:10:11 -0500 | [diff] [blame] | 418 | if (retry_estale(res, lookup_flags)) { |
| 419 | lookup_flags |= LOOKUP_REVAL; |
| 420 | goto retry; |
| 421 | } |
Dave Hansen | 6902d92 | 2006-09-30 23:29:01 -0700 | [diff] [blame] | 422 | out: |
David Howells | d84f4f9 | 2008-11-14 10:39:23 +1100 | [diff] [blame] | 423 | revert_creds(old_cred); |
| 424 | put_cred(override_cred); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 425 | return res; |
| 426 | } |
| 427 | |
Heiko Carstens | ca013e9 | 2009-01-14 14:14:19 +0100 | [diff] [blame] | 428 | SYSCALL_DEFINE2(access, const char __user *, filename, int, mode) |
Ulrich Drepper | 5590ff0 | 2006-01-18 17:43:53 -0800 | [diff] [blame] | 429 | { |
| 430 | return sys_faccessat(AT_FDCWD, filename, mode); |
| 431 | } |
| 432 | |
Heiko Carstens | 3cdad42 | 2009-01-14 14:14:22 +0100 | [diff] [blame] | 433 | SYSCALL_DEFINE1(chdir, const char __user *, filename) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 434 | { |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 435 | struct path path; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 436 | int error; |
Jeff Layton | 0291c0a | 2012-12-11 12:10:12 -0500 | [diff] [blame] | 437 | unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY; |
| 438 | retry: |
| 439 | error = user_path_at(AT_FDCWD, filename, lookup_flags, &path); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 440 | if (error) |
| 441 | goto out; |
| 442 | |
Eric Paris | 9cfcac8 | 2010-07-23 11:43:51 -0400 | [diff] [blame] | 443 | error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 444 | if (error) |
| 445 | goto dput_and_out; |
| 446 | |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 447 | set_fs_pwd(current->fs, &path); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | |
| 449 | dput_and_out: |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 450 | path_put(&path); |
Jeff Layton | 0291c0a | 2012-12-11 12:10:12 -0500 | [diff] [blame] | 451 | if (retry_estale(error, lookup_flags)) { |
| 452 | lookup_flags |= LOOKUP_REVAL; |
| 453 | goto retry; |
| 454 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 455 | out: |
| 456 | return error; |
| 457 | } |
| 458 | |
Heiko Carstens | 3cdad42 | 2009-01-14 14:14:22 +0100 | [diff] [blame] | 459 | SYSCALL_DEFINE1(fchdir, unsigned int, fd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 460 | { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 461 | struct fd f = fdget_raw(fd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 462 | struct inode *inode; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 463 | int error = -EBADF; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | |
| 465 | error = -EBADF; |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 466 | if (!f.file) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | goto out; |
| 468 | |
Al Viro | 496ad9a | 2013-01-23 17:07:38 -0500 | [diff] [blame] | 469 | inode = file_inode(f.file); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 470 | |
| 471 | error = -ENOTDIR; |
| 472 | if (!S_ISDIR(inode->i_mode)) |
| 473 | goto out_putf; |
| 474 | |
Eric Paris | 9cfcac8 | 2010-07-23 11:43:51 -0400 | [diff] [blame] | 475 | error = inode_permission(inode, MAY_EXEC | MAY_CHDIR); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 476 | if (!error) |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 477 | set_fs_pwd(current->fs, &f.file->f_path); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 478 | out_putf: |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 479 | fdput(f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 480 | out: |
| 481 | return error; |
| 482 | } |
| 483 | |
Heiko Carstens | 3480b25 | 2009-01-14 14:14:16 +0100 | [diff] [blame] | 484 | SYSCALL_DEFINE1(chroot, const char __user *, filename) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 485 | { |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 486 | struct path path; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 487 | int error; |
Jeff Layton | 2771261 | 2012-12-20 17:08:32 -0500 | [diff] [blame] | 488 | unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY; |
| 489 | retry: |
| 490 | error = user_path_at(AT_FDCWD, filename, lookup_flags, &path); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 491 | if (error) |
| 492 | goto out; |
| 493 | |
Eric Paris | 9cfcac8 | 2010-07-23 11:43:51 -0400 | [diff] [blame] | 494 | error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 495 | if (error) |
| 496 | goto dput_and_out; |
| 497 | |
| 498 | error = -EPERM; |
Eric W. Biederman | c7b96ac | 2013-03-20 12:49:49 -0700 | [diff] [blame] | 499 | if (!ns_capable(current_user_ns(), CAP_SYS_CHROOT)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 500 | goto dput_and_out; |
Tetsuo Handa | 8b8efb4 | 2009-10-04 21:49:48 +0900 | [diff] [blame] | 501 | error = security_path_chroot(&path); |
| 502 | if (error) |
| 503 | goto dput_and_out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 504 | |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 505 | set_fs_root(current->fs, &path); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | error = 0; |
| 507 | dput_and_out: |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 508 | path_put(&path); |
Jeff Layton | 2771261 | 2012-12-20 17:08:32 -0500 | [diff] [blame] | 509 | if (retry_estale(error, lookup_flags)) { |
| 510 | lookup_flags |= LOOKUP_REVAL; |
| 511 | goto retry; |
| 512 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 513 | out: |
| 514 | return error; |
| 515 | } |
| 516 | |
Al Viro | be01f9f | 2016-03-25 14:56:23 -0400 | [diff] [blame] | 517 | static int chmod_common(const struct path *path, umode_t mode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | { |
Al Viro | e57712e | 2011-07-26 04:15:54 -0400 | [diff] [blame] | 519 | struct inode *inode = path->dentry->d_inode; |
J. Bruce Fields | 27ac0ff | 2011-09-20 17:19:26 -0400 | [diff] [blame] | 520 | struct inode *delegated_inode = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 521 | struct iattr newattrs; |
Al Viro | e57712e | 2011-07-26 04:15:54 -0400 | [diff] [blame] | 522 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | |
Al Viro | e57712e | 2011-07-26 04:15:54 -0400 | [diff] [blame] | 524 | error = mnt_want_write(path->mnt); |
| 525 | if (error) |
| 526 | return error; |
J. Bruce Fields | 27ac0ff | 2011-09-20 17:19:26 -0400 | [diff] [blame] | 527 | retry_deleg: |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 528 | inode_lock(inode); |
Al Viro | cdcf116 | 2011-12-08 10:51:53 -0500 | [diff] [blame] | 529 | error = security_path_chmod(path, mode); |
Al Viro | e57712e | 2011-07-26 04:15:54 -0400 | [diff] [blame] | 530 | if (error) |
Tetsuo Handa | fe542cf | 2009-11-22 11:49:55 +0900 | [diff] [blame] | 531 | goto out_unlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 532 | newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO); |
| 533 | newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; |
J. Bruce Fields | 27ac0ff | 2011-09-20 17:19:26 -0400 | [diff] [blame] | 534 | error = notify_change(path->dentry, &newattrs, &delegated_inode); |
Tetsuo Handa | fe542cf | 2009-11-22 11:49:55 +0900 | [diff] [blame] | 535 | out_unlock: |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 536 | inode_unlock(inode); |
J. Bruce Fields | 27ac0ff | 2011-09-20 17:19:26 -0400 | [diff] [blame] | 537 | if (delegated_inode) { |
| 538 | error = break_deleg_wait(&delegated_inode); |
| 539 | if (!error) |
| 540 | goto retry_deleg; |
| 541 | } |
Al Viro | e57712e | 2011-07-26 04:15:54 -0400 | [diff] [blame] | 542 | mnt_drop_write(path->mnt); |
| 543 | return error; |
| 544 | } |
| 545 | |
Al Viro | 49f0a07 | 2011-07-26 04:22:01 -0400 | [diff] [blame] | 546 | SYSCALL_DEFINE2(fchmod, unsigned int, fd, umode_t, mode) |
Al Viro | e57712e | 2011-07-26 04:15:54 -0400 | [diff] [blame] | 547 | { |
Al Viro | 173c840 | 2013-08-30 12:48:53 -0400 | [diff] [blame] | 548 | struct fd f = fdget(fd); |
Al Viro | e57712e | 2011-07-26 04:15:54 -0400 | [diff] [blame] | 549 | int err = -EBADF; |
| 550 | |
Al Viro | 173c840 | 2013-08-30 12:48:53 -0400 | [diff] [blame] | 551 | if (f.file) { |
Al Viro | 9f45f5b | 2014-10-31 17:44:57 -0400 | [diff] [blame] | 552 | audit_file(f.file); |
Al Viro | 173c840 | 2013-08-30 12:48:53 -0400 | [diff] [blame] | 553 | err = chmod_common(&f.file->f_path, mode); |
| 554 | fdput(f); |
Al Viro | e57712e | 2011-07-26 04:15:54 -0400 | [diff] [blame] | 555 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 556 | return err; |
| 557 | } |
| 558 | |
Al Viro | 49f0a07 | 2011-07-26 04:22:01 -0400 | [diff] [blame] | 559 | SYSCALL_DEFINE3(fchmodat, int, dfd, const char __user *, filename, umode_t, mode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 560 | { |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 561 | struct path path; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 562 | int error; |
Jeff Layton | 14ff690 | 2012-12-11 12:10:13 -0500 | [diff] [blame] | 563 | unsigned int lookup_flags = LOOKUP_FOLLOW; |
| 564 | retry: |
| 565 | error = user_path_at(dfd, filename, lookup_flags, &path); |
Al Viro | e57712e | 2011-07-26 04:15:54 -0400 | [diff] [blame] | 566 | if (!error) { |
| 567 | error = chmod_common(&path, mode); |
| 568 | path_put(&path); |
Jeff Layton | 14ff690 | 2012-12-11 12:10:13 -0500 | [diff] [blame] | 569 | if (retry_estale(error, lookup_flags)) { |
| 570 | lookup_flags |= LOOKUP_REVAL; |
| 571 | goto retry; |
| 572 | } |
Al Viro | e57712e | 2011-07-26 04:15:54 -0400 | [diff] [blame] | 573 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 574 | return error; |
| 575 | } |
| 576 | |
Al Viro | 49f0a07 | 2011-07-26 04:22:01 -0400 | [diff] [blame] | 577 | SYSCALL_DEFINE2(chmod, const char __user *, filename, umode_t, mode) |
Ulrich Drepper | 5590ff0 | 2006-01-18 17:43:53 -0800 | [diff] [blame] | 578 | { |
| 579 | return sys_fchmodat(AT_FDCWD, filename, mode); |
| 580 | } |
| 581 | |
Al Viro | 7fd25da | 2016-03-25 14:44:41 -0400 | [diff] [blame] | 582 | static int chown_common(const struct path *path, uid_t user, gid_t group) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 583 | { |
Tetsuo Handa | fe542cf | 2009-11-22 11:49:55 +0900 | [diff] [blame] | 584 | struct inode *inode = path->dentry->d_inode; |
J. Bruce Fields | 27ac0ff | 2011-09-20 17:19:26 -0400 | [diff] [blame] | 585 | struct inode *delegated_inode = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 586 | int error; |
| 587 | struct iattr newattrs; |
Eric W. Biederman | 52137ab | 2012-03-03 19:52:01 -0800 | [diff] [blame] | 588 | kuid_t uid; |
| 589 | kgid_t gid; |
| 590 | |
| 591 | uid = make_kuid(current_user_ns(), user); |
| 592 | gid = make_kgid(current_user_ns(), group); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 593 | |
Andrew Elble | c1b8940 | 2015-02-23 08:51:24 -0500 | [diff] [blame] | 594 | retry_deleg: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 595 | newattrs.ia_valid = ATTR_CTIME; |
| 596 | if (user != (uid_t) -1) { |
Eric W. Biederman | 52137ab | 2012-03-03 19:52:01 -0800 | [diff] [blame] | 597 | if (!uid_valid(uid)) |
| 598 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 599 | newattrs.ia_valid |= ATTR_UID; |
Eric W. Biederman | 52137ab | 2012-03-03 19:52:01 -0800 | [diff] [blame] | 600 | newattrs.ia_uid = uid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 601 | } |
| 602 | if (group != (gid_t) -1) { |
Eric W. Biederman | 52137ab | 2012-03-03 19:52:01 -0800 | [diff] [blame] | 603 | if (!gid_valid(gid)) |
| 604 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 605 | newattrs.ia_valid |= ATTR_GID; |
Eric W. Biederman | 52137ab | 2012-03-03 19:52:01 -0800 | [diff] [blame] | 606 | newattrs.ia_gid = gid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 607 | } |
| 608 | if (!S_ISDIR(inode->i_mode)) |
Serge E. Hallyn | b537677 | 2007-10-16 23:31:36 -0700 | [diff] [blame] | 609 | newattrs.ia_valid |= |
| 610 | ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV; |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 611 | inode_lock(inode); |
Eric W. Biederman | d2b31ca | 2012-06-01 16:14:19 -0600 | [diff] [blame] | 612 | error = security_path_chown(path, uid, gid); |
Tetsuo Handa | fe542cf | 2009-11-22 11:49:55 +0900 | [diff] [blame] | 613 | if (!error) |
J. Bruce Fields | 27ac0ff | 2011-09-20 17:19:26 -0400 | [diff] [blame] | 614 | error = notify_change(path->dentry, &newattrs, &delegated_inode); |
Al Viro | 5955102 | 2016-01-22 15:40:57 -0500 | [diff] [blame] | 615 | inode_unlock(inode); |
J. Bruce Fields | 27ac0ff | 2011-09-20 17:19:26 -0400 | [diff] [blame] | 616 | if (delegated_inode) { |
| 617 | error = break_deleg_wait(&delegated_inode); |
| 618 | if (!error) |
| 619 | goto retry_deleg; |
| 620 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 621 | return error; |
| 622 | } |
| 623 | |
Heiko Carstens | 6559eed8 | 2009-01-14 14:14:32 +0100 | [diff] [blame] | 624 | SYSCALL_DEFINE5(fchownat, int, dfd, const char __user *, filename, uid_t, user, |
| 625 | gid_t, group, int, flag) |
Ulrich Drepper | 5590ff0 | 2006-01-18 17:43:53 -0800 | [diff] [blame] | 626 | { |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 627 | struct path path; |
Ulrich Drepper | 5590ff0 | 2006-01-18 17:43:53 -0800 | [diff] [blame] | 628 | int error = -EINVAL; |
Al Viro | 65cfc67 | 2011-03-13 15:56:26 -0400 | [diff] [blame] | 629 | int lookup_flags; |
Ulrich Drepper | 5590ff0 | 2006-01-18 17:43:53 -0800 | [diff] [blame] | 630 | |
Al Viro | 65cfc67 | 2011-03-13 15:56:26 -0400 | [diff] [blame] | 631 | if ((flag & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0) |
Ulrich Drepper | 5590ff0 | 2006-01-18 17:43:53 -0800 | [diff] [blame] | 632 | goto out; |
| 633 | |
Al Viro | 65cfc67 | 2011-03-13 15:56:26 -0400 | [diff] [blame] | 634 | lookup_flags = (flag & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; |
| 635 | if (flag & AT_EMPTY_PATH) |
| 636 | lookup_flags |= LOOKUP_EMPTY; |
Jeff Layton | 99a5df3 | 2012-12-11 12:10:13 -0500 | [diff] [blame] | 637 | retry: |
Al Viro | 65cfc67 | 2011-03-13 15:56:26 -0400 | [diff] [blame] | 638 | error = user_path_at(dfd, filename, lookup_flags, &path); |
Dave Hansen | 6902d92 | 2006-09-30 23:29:01 -0700 | [diff] [blame] | 639 | if (error) |
| 640 | goto out; |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 641 | error = mnt_want_write(path.mnt); |
Dave Hansen | 2af482a | 2008-02-15 14:37:50 -0800 | [diff] [blame] | 642 | if (error) |
| 643 | goto out_release; |
Tetsuo Handa | fe542cf | 2009-11-22 11:49:55 +0900 | [diff] [blame] | 644 | error = chown_common(&path, user, group); |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 645 | mnt_drop_write(path.mnt); |
Dave Hansen | 2af482a | 2008-02-15 14:37:50 -0800 | [diff] [blame] | 646 | out_release: |
Al Viro | 2d8f303 | 2008-07-22 09:59:21 -0400 | [diff] [blame] | 647 | path_put(&path); |
Jeff Layton | 99a5df3 | 2012-12-11 12:10:13 -0500 | [diff] [blame] | 648 | if (retry_estale(error, lookup_flags)) { |
| 649 | lookup_flags |= LOOKUP_REVAL; |
| 650 | goto retry; |
| 651 | } |
Ulrich Drepper | 5590ff0 | 2006-01-18 17:43:53 -0800 | [diff] [blame] | 652 | out: |
| 653 | return error; |
| 654 | } |
| 655 | |
David Howells | 55e4def | 2012-06-25 12:55:09 +0100 | [diff] [blame] | 656 | SYSCALL_DEFINE3(chown, const char __user *, filename, uid_t, user, gid_t, group) |
| 657 | { |
| 658 | return sys_fchownat(AT_FDCWD, filename, user, group, 0); |
| 659 | } |
| 660 | |
Heiko Carstens | ca013e9 | 2009-01-14 14:14:19 +0100 | [diff] [blame] | 661 | SYSCALL_DEFINE3(lchown, const char __user *, filename, uid_t, user, gid_t, group) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 662 | { |
David Howells | 55e4def | 2012-06-25 12:55:09 +0100 | [diff] [blame] | 663 | return sys_fchownat(AT_FDCWD, filename, user, group, |
| 664 | AT_SYMLINK_NOFOLLOW); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 665 | } |
| 666 | |
Heiko Carstens | ca013e9 | 2009-01-14 14:14:19 +0100 | [diff] [blame] | 667 | SYSCALL_DEFINE3(fchown, unsigned int, fd, uid_t, user, gid_t, group) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 668 | { |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 669 | struct fd f = fdget(fd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 670 | int error = -EBADF; |
| 671 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 672 | if (!f.file) |
Dave Hansen | 6902d92 | 2006-09-30 23:29:01 -0700 | [diff] [blame] | 673 | goto out; |
| 674 | |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 675 | error = mnt_want_write_file(f.file); |
Dave Hansen | 2af482a | 2008-02-15 14:37:50 -0800 | [diff] [blame] | 676 | if (error) |
| 677 | goto out_fput; |
Al Viro | 9f45f5b | 2014-10-31 17:44:57 -0400 | [diff] [blame] | 678 | audit_file(f.file); |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 679 | error = chown_common(&f.file->f_path, user, group); |
| 680 | mnt_drop_write_file(f.file); |
Dave Hansen | 2af482a | 2008-02-15 14:37:50 -0800 | [diff] [blame] | 681 | out_fput: |
Al Viro | 2903ff0 | 2012-08-28 12:52:22 -0400 | [diff] [blame] | 682 | fdput(f); |
Dave Hansen | 6902d92 | 2006-09-30 23:29:01 -0700 | [diff] [blame] | 683 | out: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 684 | return error; |
| 685 | } |
| 686 | |
Miklos Szeredi | 90ad1a8 | 2012-05-21 17:30:15 +0200 | [diff] [blame] | 687 | int open_check_o_direct(struct file *f) |
| 688 | { |
| 689 | /* NB: we're sure to have correct a_ops only after f_op->open */ |
| 690 | if (f->f_flags & O_DIRECT) { |
Matthew Wilcox | e748dcd | 2015-02-16 15:59:12 -0800 | [diff] [blame] | 691 | if (!f->f_mapping->a_ops || !f->f_mapping->a_ops->direct_IO) |
Miklos Szeredi | 90ad1a8 | 2012-05-21 17:30:15 +0200 | [diff] [blame] | 692 | return -EINVAL; |
Miklos Szeredi | 90ad1a8 | 2012-05-21 17:30:15 +0200 | [diff] [blame] | 693 | } |
| 694 | return 0; |
| 695 | } |
| 696 | |
Al Viro | 02e5180 | 2012-06-10 14:32:45 -0400 | [diff] [blame] | 697 | static int do_dentry_open(struct file *f, |
David Howells | 4bacc9c | 2015-06-18 14:32:31 +0100 | [diff] [blame] | 698 | struct inode *inode, |
Al Viro | 96b7e57 | 2012-06-10 14:22:04 -0400 | [diff] [blame] | 699 | int (*open)(struct inode *, struct file *), |
| 700 | const struct cred *cred) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 701 | { |
Al Viro | 1abf0c7 | 2011-03-13 03:51:11 -0400 | [diff] [blame] | 702 | static const struct file_operations empty_fops = {}; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 703 | int error; |
| 704 | |
Al Viro | 5300990 | 2009-12-19 10:15:07 -0500 | [diff] [blame] | 705 | f->f_mode = OPEN_FMODE(f->f_flags) | FMODE_LSEEK | |
Peter Staubach | a1a5b3d | 2005-09-13 01:25:12 -0700 | [diff] [blame] | 706 | FMODE_PREAD | FMODE_PWRITE; |
Al Viro | 1abf0c7 | 2011-03-13 03:51:11 -0400 | [diff] [blame] | 707 | |
Al Viro | b5bcdda | 2012-07-20 23:28:46 +0400 | [diff] [blame] | 708 | path_get(&f->f_path); |
David Howells | 4bacc9c | 2015-06-18 14:32:31 +0100 | [diff] [blame] | 709 | f->f_inode = inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 710 | f->f_mapping = inode->i_mapping; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 711 | |
Al Viro | 3f4d5a0 | 2014-03-14 09:43:29 -0400 | [diff] [blame] | 712 | if (unlikely(f->f_flags & O_PATH)) { |
| 713 | f->f_mode = FMODE_PATH; |
Al Viro | 1abf0c7 | 2011-03-13 03:51:11 -0400 | [diff] [blame] | 714 | f->f_op = &empty_fops; |
Al Viro | 96b7e57 | 2012-06-10 14:22:04 -0400 | [diff] [blame] | 715 | return 0; |
Al Viro | 1abf0c7 | 2011-03-13 03:51:11 -0400 | [diff] [blame] | 716 | } |
| 717 | |
Al Viro | dd20908 | 2014-03-14 10:56:20 -0400 | [diff] [blame] | 718 | if (f->f_mode & FMODE_WRITE && !special_file(inode->i_mode)) { |
Al Viro | 0ccb286 | 2014-03-14 10:40:46 -0400 | [diff] [blame] | 719 | error = get_write_access(inode); |
Al Viro | 3f4d5a0 | 2014-03-14 09:43:29 -0400 | [diff] [blame] | 720 | if (unlikely(error)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 721 | goto cleanup_file; |
Al Viro | 0ccb286 | 2014-03-14 10:40:46 -0400 | [diff] [blame] | 722 | error = __mnt_want_write(f->f_path.mnt); |
Al Viro | 3f4d5a0 | 2014-03-14 09:43:29 -0400 | [diff] [blame] | 723 | if (unlikely(error)) { |
Al Viro | 0ccb286 | 2014-03-14 10:40:46 -0400 | [diff] [blame] | 724 | put_write_access(inode); |
| 725 | goto cleanup_file; |
| 726 | } |
Al Viro | 83f936c | 2014-03-14 12:02:47 -0400 | [diff] [blame] | 727 | f->f_mode |= FMODE_WRITER; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 728 | } |
| 729 | |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 730 | /* POSIX.1-2008/SUSv4 Section XSI 2.9.7 */ |
Al Viro | 63b6df1 | 2016-04-20 17:08:21 -0400 | [diff] [blame] | 731 | if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)) |
Linus Torvalds | 9c225f2 | 2014-03-03 09:36:58 -0800 | [diff] [blame] | 732 | f->f_mode |= FMODE_ATOMIC_POS; |
| 733 | |
Al Viro | 1abf0c7 | 2011-03-13 03:51:11 -0400 | [diff] [blame] | 734 | f->f_op = fops_get(inode->i_fop); |
Al Viro | 72c2d53 | 2013-09-22 16:27:52 -0400 | [diff] [blame] | 735 | if (unlikely(WARN_ON(!f->f_op))) { |
| 736 | error = -ENODEV; |
| 737 | goto cleanup_all; |
| 738 | } |
Al Viro | 1abf0c7 | 2011-03-13 03:51:11 -0400 | [diff] [blame] | 739 | |
Eric Paris | 83d4985 | 2012-04-04 13:45:40 -0400 | [diff] [blame] | 740 | error = security_file_open(f, cred); |
Yuichi Nakamura | 788e7dd | 2007-09-14 09:27:07 +0900 | [diff] [blame] | 741 | if (error) |
| 742 | goto cleanup_all; |
| 743 | |
Miklos Szeredi | c568d68 | 2016-09-16 12:44:20 +0200 | [diff] [blame] | 744 | error = break_lease(locks_inode(f), f->f_flags); |
J. Bruce Fields | f3c7691e | 2011-09-21 10:58:13 -0400 | [diff] [blame] | 745 | if (error) |
| 746 | goto cleanup_all; |
| 747 | |
Al Viro | 72c2d53 | 2013-09-22 16:27:52 -0400 | [diff] [blame] | 748 | if (!open) |
Trond Myklebust | 834f2a4 | 2005-10-18 14:20:16 -0700 | [diff] [blame] | 749 | open = f->f_op->open; |
| 750 | if (open) { |
| 751 | error = open(inode, f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 752 | if (error) |
| 753 | goto cleanup_all; |
| 754 | } |
Mimi Zohar | 890275b5 | 2010-11-02 10:13:07 -0400 | [diff] [blame] | 755 | if ((f->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) |
| 756 | i_readcount_inc(inode); |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 757 | if ((f->f_mode & FMODE_READ) && |
Al Viro | 8436318 | 2015-04-04 01:14:53 -0400 | [diff] [blame] | 758 | likely(f->f_op->read || f->f_op->read_iter)) |
Al Viro | 7f7f25e | 2014-02-11 17:49:24 -0500 | [diff] [blame] | 759 | f->f_mode |= FMODE_CAN_READ; |
Al Viro | 293bc98 | 2014-02-11 18:37:41 -0500 | [diff] [blame] | 760 | if ((f->f_mode & FMODE_WRITE) && |
Al Viro | 8436318 | 2015-04-04 01:14:53 -0400 | [diff] [blame] | 761 | likely(f->f_op->write || f->f_op->write_iter)) |
Al Viro | 7f7f25e | 2014-02-11 17:49:24 -0500 | [diff] [blame] | 762 | f->f_mode |= FMODE_CAN_WRITE; |
Trond Myklebust | 834f2a4 | 2005-10-18 14:20:16 -0700 | [diff] [blame] | 763 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 764 | f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC); |
| 765 | |
| 766 | file_ra_state_init(&f->f_ra, f->f_mapping->host->i_mapping); |
| 767 | |
Al Viro | 96b7e57 | 2012-06-10 14:22:04 -0400 | [diff] [blame] | 768 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 769 | |
| 770 | cleanup_all: |
| 771 | fops_put(f->f_op); |
Al Viro | 83f936c | 2014-03-14 12:02:47 -0400 | [diff] [blame] | 772 | if (f->f_mode & FMODE_WRITER) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 773 | put_write_access(inode); |
Al Viro | 83f936c | 2014-03-14 12:02:47 -0400 | [diff] [blame] | 774 | __mnt_drop_write(f->f_path.mnt); |
Dave Hansen | 4a3fd21 | 2008-02-15 14:37:48 -0800 | [diff] [blame] | 775 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 776 | cleanup_file: |
Al Viro | 02e5180 | 2012-06-10 14:32:45 -0400 | [diff] [blame] | 777 | path_put(&f->f_path); |
| 778 | f->f_path.mnt = NULL; |
| 779 | f->f_path.dentry = NULL; |
Al Viro | dd37978 | 2013-03-01 19:48:30 -0500 | [diff] [blame] | 780 | f->f_inode = NULL; |
Al Viro | 96b7e57 | 2012-06-10 14:22:04 -0400 | [diff] [blame] | 781 | return error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 782 | } |
| 783 | |
Trond Myklebust | 834f2a4 | 2005-10-18 14:20:16 -0700 | [diff] [blame] | 784 | /** |
Miklos Szeredi | d18e900 | 2012-06-05 15:10:17 +0200 | [diff] [blame] | 785 | * finish_open - finish opening a file |
Miklos Szeredi | 0854d45 | 2013-09-16 14:51:55 +0200 | [diff] [blame] | 786 | * @file: file pointer |
Miklos Szeredi | d18e900 | 2012-06-05 15:10:17 +0200 | [diff] [blame] | 787 | * @dentry: pointer to dentry |
| 788 | * @open: open callback |
Miklos Szeredi | 0854d45 | 2013-09-16 14:51:55 +0200 | [diff] [blame] | 789 | * @opened: state of open |
Miklos Szeredi | d18e900 | 2012-06-05 15:10:17 +0200 | [diff] [blame] | 790 | * |
| 791 | * This can be used to finish opening a file passed to i_op->atomic_open(). |
| 792 | * |
| 793 | * If the open callback is set to NULL, then the standard f_op->open() |
| 794 | * filesystem callback is substituted. |
Miklos Szeredi | 0854d45 | 2013-09-16 14:51:55 +0200 | [diff] [blame] | 795 | * |
| 796 | * NB: the dentry reference is _not_ consumed. If, for example, the dentry is |
| 797 | * the return value of d_splice_alias(), then the caller needs to perform dput() |
| 798 | * on it after finish_open(). |
| 799 | * |
| 800 | * On successful return @file is a fully instantiated open file. After this, if |
| 801 | * an error occurs in ->atomic_open(), it needs to clean up with fput(). |
| 802 | * |
| 803 | * Returns zero on success or -errno if the open failed. |
Miklos Szeredi | d18e900 | 2012-06-05 15:10:17 +0200 | [diff] [blame] | 804 | */ |
Al Viro | 30d90494 | 2012-06-22 12:40:19 +0400 | [diff] [blame] | 805 | int finish_open(struct file *file, struct dentry *dentry, |
| 806 | int (*open)(struct inode *, struct file *), |
| 807 | int *opened) |
Miklos Szeredi | d18e900 | 2012-06-05 15:10:17 +0200 | [diff] [blame] | 808 | { |
Al Viro | 96b7e57 | 2012-06-10 14:22:04 -0400 | [diff] [blame] | 809 | int error; |
Al Viro | 3d8a00d | 2012-06-10 05:04:43 -0400 | [diff] [blame] | 810 | BUG_ON(*opened & FILE_OPENED); /* once it's opened, it's opened */ |
Miklos Szeredi | d18e900 | 2012-06-05 15:10:17 +0200 | [diff] [blame] | 811 | |
Al Viro | b5bcdda | 2012-07-20 23:28:46 +0400 | [diff] [blame] | 812 | file->f_path.dentry = dentry; |
David Howells | 4bacc9c | 2015-06-18 14:32:31 +0100 | [diff] [blame] | 813 | error = do_dentry_open(file, d_backing_inode(dentry), open, |
| 814 | current_cred()); |
Al Viro | 96b7e57 | 2012-06-10 14:22:04 -0400 | [diff] [blame] | 815 | if (!error) |
Al Viro | 4723768 | 2012-06-10 05:01:45 -0400 | [diff] [blame] | 816 | *opened |= FILE_OPENED; |
Miklos Szeredi | d18e900 | 2012-06-05 15:10:17 +0200 | [diff] [blame] | 817 | |
Al Viro | 96b7e57 | 2012-06-10 14:22:04 -0400 | [diff] [blame] | 818 | return error; |
Miklos Szeredi | d18e900 | 2012-06-05 15:10:17 +0200 | [diff] [blame] | 819 | } |
| 820 | EXPORT_SYMBOL(finish_open); |
| 821 | |
| 822 | /** |
| 823 | * finish_no_open - finish ->atomic_open() without opening the file |
| 824 | * |
Miklos Szeredi | 0854d45 | 2013-09-16 14:51:55 +0200 | [diff] [blame] | 825 | * @file: file pointer |
Miklos Szeredi | d18e900 | 2012-06-05 15:10:17 +0200 | [diff] [blame] | 826 | * @dentry: dentry or NULL (as returned from ->lookup()) |
| 827 | * |
| 828 | * This can be used to set the result of a successful lookup in ->atomic_open(). |
Miklos Szeredi | 0854d45 | 2013-09-16 14:51:55 +0200 | [diff] [blame] | 829 | * |
| 830 | * NB: unlike finish_open() this function does consume the dentry reference and |
| 831 | * the caller need not dput() it. |
| 832 | * |
| 833 | * Returns "1" which must be the return value of ->atomic_open() after having |
| 834 | * called this function. |
Miklos Szeredi | d18e900 | 2012-06-05 15:10:17 +0200 | [diff] [blame] | 835 | */ |
Al Viro | e45198a | 2012-06-10 06:48:09 -0400 | [diff] [blame] | 836 | int finish_no_open(struct file *file, struct dentry *dentry) |
Miklos Szeredi | d18e900 | 2012-06-05 15:10:17 +0200 | [diff] [blame] | 837 | { |
Al Viro | 30d90494 | 2012-06-22 12:40:19 +0400 | [diff] [blame] | 838 | file->f_path.dentry = dentry; |
Al Viro | e45198a | 2012-06-10 06:48:09 -0400 | [diff] [blame] | 839 | return 1; |
Miklos Szeredi | d18e900 | 2012-06-05 15:10:17 +0200 | [diff] [blame] | 840 | } |
| 841 | EXPORT_SYMBOL(finish_no_open); |
| 842 | |
Miklos Szeredi | 9bf39ab | 2015-06-19 10:29:13 +0200 | [diff] [blame] | 843 | char *file_path(struct file *filp, char *buf, int buflen) |
| 844 | { |
| 845 | return d_path(&filp->f_path, buf, buflen); |
| 846 | } |
| 847 | EXPORT_SYMBOL(file_path); |
| 848 | |
David Howells | 4bacc9c | 2015-06-18 14:32:31 +0100 | [diff] [blame] | 849 | /** |
| 850 | * vfs_open - open the file at the given path |
| 851 | * @path: path to open |
| 852 | * @file: newly allocated file with f_flag initialized |
| 853 | * @cred: credentials to use |
| 854 | */ |
| 855 | int vfs_open(const struct path *path, struct file *file, |
| 856 | const struct cred *cred) |
| 857 | { |
Miklos Szeredi | 2d90267 | 2016-06-30 08:53:27 +0200 | [diff] [blame] | 858 | struct dentry *dentry = d_real(path->dentry, NULL, file->f_flags); |
Miklos Szeredi | 54d5ca8 | 2016-05-11 01:16:37 +0200 | [diff] [blame] | 859 | |
Miklos Szeredi | 2d90267 | 2016-06-30 08:53:27 +0200 | [diff] [blame] | 860 | if (IS_ERR(dentry)) |
| 861 | return PTR_ERR(dentry); |
David Howells | 4bacc9c | 2015-06-18 14:32:31 +0100 | [diff] [blame] | 862 | |
| 863 | file->f_path = *path; |
Miklos Szeredi | 2d90267 | 2016-06-30 08:53:27 +0200 | [diff] [blame] | 864 | return do_dentry_open(file, d_backing_inode(dentry), NULL, cred); |
David Howells | 4bacc9c | 2015-06-18 14:32:31 +0100 | [diff] [blame] | 865 | } |
| 866 | |
Al Viro | 765927b | 2012-06-26 21:58:53 +0400 | [diff] [blame] | 867 | struct file *dentry_open(const struct path *path, int flags, |
David Howells | 745ca24 | 2008-11-14 10:39:22 +1100 | [diff] [blame] | 868 | const struct cred *cred) |
Peter Staubach | a1a5b3d | 2005-09-13 01:25:12 -0700 | [diff] [blame] | 869 | { |
| 870 | int error; |
| 871 | struct file *f; |
| 872 | |
David Howells | e0e8173 | 2009-09-02 09:13:40 +0100 | [diff] [blame] | 873 | validate_creds(cred); |
| 874 | |
Tetsuo Handa | c212f9a | 2011-01-19 21:08:41 +0900 | [diff] [blame] | 875 | /* We must always pass in a valid mount pointer. */ |
Al Viro | 765927b | 2012-06-26 21:58:53 +0400 | [diff] [blame] | 876 | BUG_ON(!path->mnt); |
Christoph Hellwig | 322ee5b | 2008-02-15 14:37:24 -0800 | [diff] [blame] | 877 | |
Peter Staubach | a1a5b3d | 2005-09-13 01:25:12 -0700 | [diff] [blame] | 878 | f = get_empty_filp(); |
Al Viro | 1afc99b | 2013-02-14 20:41:04 -0500 | [diff] [blame] | 879 | if (!IS_ERR(f)) { |
| 880 | f->f_flags = flags; |
Miklos Szeredi | 4aa7c63 | 2014-10-24 00:14:35 +0200 | [diff] [blame] | 881 | error = vfs_open(path, f, cred); |
Al Viro | 1afc99b | 2013-02-14 20:41:04 -0500 | [diff] [blame] | 882 | if (!error) { |
| 883 | /* from now on we need fput() to dispose of f */ |
| 884 | error = open_check_o_direct(f); |
| 885 | if (error) { |
| 886 | fput(f); |
| 887 | f = ERR_PTR(error); |
| 888 | } |
| 889 | } else { |
| 890 | put_filp(f); |
Al Viro | 2a027e7 | 2012-06-10 14:24:38 -0400 | [diff] [blame] | 891 | f = ERR_PTR(error); |
| 892 | } |
Al Viro | 2a027e7 | 2012-06-10 14:24:38 -0400 | [diff] [blame] | 893 | } |
| 894 | return f; |
Peter Staubach | a1a5b3d | 2005-09-13 01:25:12 -0700 | [diff] [blame] | 895 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 896 | EXPORT_SYMBOL(dentry_open); |
| 897 | |
Al Viro | a218d0f | 2011-11-21 14:59:34 -0500 | [diff] [blame] | 898 | static inline int build_open_flags(int flags, umode_t mode, struct open_flags *op) |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 899 | { |
| 900 | int lookup_flags = 0; |
Al Viro | 62fb4a1 | 2015-12-26 22:33:24 -0500 | [diff] [blame] | 901 | int acc_mode = ACC_MODE(flags); |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 902 | |
Andy Lutomirski | e305f48 | 2013-08-01 21:07:52 -0700 | [diff] [blame] | 903 | if (flags & (O_CREAT | __O_TMPFILE)) |
Miklos Szeredi | e68726f | 2012-08-15 13:01:24 +0200 | [diff] [blame] | 904 | op->mode = (mode & S_IALLUGO) | S_IFREG; |
| 905 | else |
| 906 | op->mode = 0; |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 907 | |
| 908 | /* Must never be set by userspace */ |
Al Viro | c6f3d81 | 2012-08-26 11:01:04 -0400 | [diff] [blame] | 909 | flags &= ~FMODE_NONOTIFY & ~O_CLOEXEC; |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 910 | |
| 911 | /* |
| 912 | * O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only |
| 913 | * check for O_DSYNC if the need any syncing at all we enforce it's |
| 914 | * always set instead of having to deal with possibly weird behaviour |
| 915 | * for malicious applications setting only __O_SYNC. |
| 916 | */ |
| 917 | if (flags & __O_SYNC) |
| 918 | flags |= O_DSYNC; |
| 919 | |
Al Viro | bb458c6 | 2013-07-13 13:26:37 +0400 | [diff] [blame] | 920 | if (flags & __O_TMPFILE) { |
| 921 | if ((flags & O_TMPFILE_MASK) != O_TMPFILE) |
Al Viro | 60545d0 | 2013-06-07 01:20:27 -0400 | [diff] [blame] | 922 | return -EINVAL; |
Al Viro | ba57ea6 | 2013-07-20 03:11:32 +0400 | [diff] [blame] | 923 | if (!(acc_mode & MAY_WRITE)) |
| 924 | return -EINVAL; |
Al Viro | 60545d0 | 2013-06-07 01:20:27 -0400 | [diff] [blame] | 925 | } else if (flags & O_PATH) { |
| 926 | /* |
| 927 | * If we have O_PATH in the open flag. Then we |
| 928 | * cannot have anything other than the below set of flags |
| 929 | */ |
Al Viro | 1abf0c7 | 2011-03-13 03:51:11 -0400 | [diff] [blame] | 930 | flags &= O_DIRECTORY | O_NOFOLLOW | O_PATH; |
| 931 | acc_mode = 0; |
Al Viro | 1abf0c7 | 2011-03-13 03:51:11 -0400 | [diff] [blame] | 932 | } |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 933 | |
Al Viro | 1abf0c7 | 2011-03-13 03:51:11 -0400 | [diff] [blame] | 934 | op->open_flag = flags; |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 935 | |
| 936 | /* O_TRUNC implies we need access checks for write permissions */ |
| 937 | if (flags & O_TRUNC) |
| 938 | acc_mode |= MAY_WRITE; |
| 939 | |
| 940 | /* Allow the LSM permission hook to distinguish append |
| 941 | access from general write access. */ |
| 942 | if (flags & O_APPEND) |
| 943 | acc_mode |= MAY_APPEND; |
| 944 | |
| 945 | op->acc_mode = acc_mode; |
| 946 | |
Al Viro | 1abf0c7 | 2011-03-13 03:51:11 -0400 | [diff] [blame] | 947 | op->intent = flags & O_PATH ? 0 : LOOKUP_OPEN; |
| 948 | |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 949 | if (flags & O_CREAT) { |
| 950 | op->intent |= LOOKUP_CREATE; |
| 951 | if (flags & O_EXCL) |
| 952 | op->intent |= LOOKUP_EXCL; |
| 953 | } |
| 954 | |
| 955 | if (flags & O_DIRECTORY) |
| 956 | lookup_flags |= LOOKUP_DIRECTORY; |
| 957 | if (!(flags & O_NOFOLLOW)) |
| 958 | lookup_flags |= LOOKUP_FOLLOW; |
Al Viro | f9652e1 | 2013-06-11 08:23:01 +0400 | [diff] [blame] | 959 | op->lookup_flags = lookup_flags; |
| 960 | return 0; |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 961 | } |
| 962 | |
| 963 | /** |
Jeff Layton | 669abf4 | 2012-10-10 16:43:10 -0400 | [diff] [blame] | 964 | * file_open_name - open file and return file pointer |
| 965 | * |
| 966 | * @name: struct filename containing path to open |
| 967 | * @flags: open flags as per the open(2) second argument |
| 968 | * @mode: mode for the new file if O_CREAT is set, else ignored |
| 969 | * |
| 970 | * This is the helper to open a file from kernelspace if you really |
| 971 | * have to. But in generally you should not do this, so please move |
| 972 | * along, nothing to see here.. |
| 973 | */ |
| 974 | struct file *file_open_name(struct filename *name, int flags, umode_t mode) |
| 975 | { |
| 976 | struct open_flags op; |
Al Viro | f9652e1 | 2013-06-11 08:23:01 +0400 | [diff] [blame] | 977 | int err = build_open_flags(flags, mode, &op); |
| 978 | return err ? ERR_PTR(err) : do_filp_open(AT_FDCWD, name, &op); |
Jeff Layton | 669abf4 | 2012-10-10 16:43:10 -0400 | [diff] [blame] | 979 | } |
| 980 | |
| 981 | /** |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 982 | * filp_open - open file and return file pointer |
| 983 | * |
| 984 | * @filename: path to open |
| 985 | * @flags: open flags as per the open(2) second argument |
| 986 | * @mode: mode for the new file if O_CREAT is set, else ignored |
| 987 | * |
| 988 | * This is the helper to open a file from kernelspace if you really |
| 989 | * have to. But in generally you should not do this, so please move |
| 990 | * along, nothing to see here.. |
| 991 | */ |
Al Viro | a218d0f | 2011-11-21 14:59:34 -0500 | [diff] [blame] | 992 | struct file *filp_open(const char *filename, int flags, umode_t mode) |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 993 | { |
Paul Moore | 5168910 | 2015-01-22 00:00:03 -0500 | [diff] [blame] | 994 | struct filename *name = getname_kernel(filename); |
| 995 | struct file *file = ERR_CAST(name); |
| 996 | |
| 997 | if (!IS_ERR(name)) { |
| 998 | file = file_open_name(name, flags, mode); |
| 999 | putname(name); |
| 1000 | } |
| 1001 | return file; |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 1002 | } |
| 1003 | EXPORT_SYMBOL(filp_open); |
| 1004 | |
Al Viro | 73d049a | 2011-03-11 12:08:24 -0500 | [diff] [blame] | 1005 | struct file *file_open_root(struct dentry *dentry, struct vfsmount *mnt, |
Jann Horn | 378c652 | 2016-03-22 14:25:36 -0700 | [diff] [blame] | 1006 | const char *filename, int flags, umode_t mode) |
Al Viro | 73d049a | 2011-03-11 12:08:24 -0500 | [diff] [blame] | 1007 | { |
| 1008 | struct open_flags op; |
Jann Horn | 378c652 | 2016-03-22 14:25:36 -0700 | [diff] [blame] | 1009 | int err = build_open_flags(flags, mode, &op); |
Al Viro | f9652e1 | 2013-06-11 08:23:01 +0400 | [diff] [blame] | 1010 | if (err) |
| 1011 | return ERR_PTR(err); |
Al Viro | f9652e1 | 2013-06-11 08:23:01 +0400 | [diff] [blame] | 1012 | return do_file_open_root(dentry, mnt, filename, &op); |
Al Viro | 73d049a | 2011-03-11 12:08:24 -0500 | [diff] [blame] | 1013 | } |
| 1014 | EXPORT_SYMBOL(file_open_root); |
| 1015 | |
James Bottomley | 9a08c35 | 2016-02-17 16:49:38 -0800 | [diff] [blame] | 1016 | struct file *filp_clone_open(struct file *oldfile) |
| 1017 | { |
| 1018 | struct file *file; |
| 1019 | int retval; |
| 1020 | |
| 1021 | file = get_empty_filp(); |
| 1022 | if (IS_ERR(file)) |
| 1023 | return file; |
| 1024 | |
| 1025 | file->f_flags = oldfile->f_flags; |
| 1026 | retval = vfs_open(&oldfile->f_path, file, oldfile->f_cred); |
| 1027 | if (retval) { |
| 1028 | put_filp(file); |
| 1029 | return ERR_PTR(retval); |
| 1030 | } |
| 1031 | |
| 1032 | return file; |
| 1033 | } |
| 1034 | EXPORT_SYMBOL(filp_clone_open); |
| 1035 | |
Al Viro | a218d0f | 2011-11-21 14:59:34 -0500 | [diff] [blame] | 1036 | long do_sys_open(int dfd, const char __user *filename, int flags, umode_t mode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1037 | { |
Al Viro | 47c805d | 2011-02-23 17:44:09 -0500 | [diff] [blame] | 1038 | struct open_flags op; |
Al Viro | f9652e1 | 2013-06-11 08:23:01 +0400 | [diff] [blame] | 1039 | int fd = build_open_flags(flags, mode, &op); |
| 1040 | struct filename *tmp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1041 | |
Al Viro | f9652e1 | 2013-06-11 08:23:01 +0400 | [diff] [blame] | 1042 | if (fd) |
| 1043 | return fd; |
| 1044 | |
| 1045 | tmp = getname(filename); |
| 1046 | if (IS_ERR(tmp)) |
| 1047 | return PTR_ERR(tmp); |
| 1048 | |
| 1049 | fd = get_unused_fd_flags(flags); |
| 1050 | if (fd >= 0) { |
| 1051 | struct file *f = do_filp_open(dfd, tmp, &op); |
| 1052 | if (IS_ERR(f)) { |
| 1053 | put_unused_fd(fd); |
| 1054 | fd = PTR_ERR(f); |
| 1055 | } else { |
| 1056 | fsnotify_open(f); |
| 1057 | fd_install(fd, f); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1058 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1059 | } |
Al Viro | f9652e1 | 2013-06-11 08:23:01 +0400 | [diff] [blame] | 1060 | putname(tmp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1061 | return fd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1062 | } |
Miklos Szeredi | e922efc | 2005-09-06 15:18:25 -0700 | [diff] [blame] | 1063 | |
Al Viro | a218d0f | 2011-11-21 14:59:34 -0500 | [diff] [blame] | 1064 | SYSCALL_DEFINE3(open, const char __user *, filename, int, flags, umode_t, mode) |
Miklos Szeredi | e922efc | 2005-09-06 15:18:25 -0700 | [diff] [blame] | 1065 | { |
| 1066 | if (force_o_largefile()) |
| 1067 | flags |= O_LARGEFILE; |
| 1068 | |
Al Viro | 2cf0966 | 2013-01-21 15:25:54 -0500 | [diff] [blame] | 1069 | return do_sys_open(AT_FDCWD, filename, flags, mode); |
Miklos Szeredi | e922efc | 2005-09-06 15:18:25 -0700 | [diff] [blame] | 1070 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1071 | |
Heiko Carstens | 6559eed8 | 2009-01-14 14:14:32 +0100 | [diff] [blame] | 1072 | SYSCALL_DEFINE4(openat, int, dfd, const char __user *, filename, int, flags, |
Al Viro | a218d0f | 2011-11-21 14:59:34 -0500 | [diff] [blame] | 1073 | umode_t, mode) |
Ulrich Drepper | 5590ff0 | 2006-01-18 17:43:53 -0800 | [diff] [blame] | 1074 | { |
| 1075 | if (force_o_largefile()) |
| 1076 | flags |= O_LARGEFILE; |
| 1077 | |
Al Viro | 2cf0966 | 2013-01-21 15:25:54 -0500 | [diff] [blame] | 1078 | return do_sys_open(dfd, filename, flags, mode); |
Ulrich Drepper | 5590ff0 | 2006-01-18 17:43:53 -0800 | [diff] [blame] | 1079 | } |
Ulrich Drepper | 5590ff0 | 2006-01-18 17:43:53 -0800 | [diff] [blame] | 1080 | |
Al Viro | e35d49f | 2017-04-08 18:15:12 -0400 | [diff] [blame] | 1081 | #ifdef CONFIG_COMPAT |
| 1082 | /* |
| 1083 | * Exactly like sys_open(), except that it doesn't set the |
| 1084 | * O_LARGEFILE flag. |
| 1085 | */ |
| 1086 | COMPAT_SYSCALL_DEFINE3(open, const char __user *, filename, int, flags, umode_t, mode) |
| 1087 | { |
| 1088 | return do_sys_open(AT_FDCWD, filename, flags, mode); |
| 1089 | } |
| 1090 | |
| 1091 | /* |
| 1092 | * Exactly like sys_openat(), except that it doesn't set the |
| 1093 | * O_LARGEFILE flag. |
| 1094 | */ |
| 1095 | COMPAT_SYSCALL_DEFINE4(openat, int, dfd, const char __user *, filename, int, flags, umode_t, mode) |
| 1096 | { |
| 1097 | return do_sys_open(dfd, filename, flags, mode); |
| 1098 | } |
| 1099 | #endif |
| 1100 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1101 | #ifndef __alpha__ |
| 1102 | |
| 1103 | /* |
| 1104 | * For backward compatibility? Maybe this should be moved |
| 1105 | * into arch/i386 instead? |
| 1106 | */ |
Al Viro | a218d0f | 2011-11-21 14:59:34 -0500 | [diff] [blame] | 1107 | SYSCALL_DEFINE2(creat, const char __user *, pathname, umode_t, mode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1108 | { |
| 1109 | return sys_open(pathname, O_CREAT | O_WRONLY | O_TRUNC, mode); |
| 1110 | } |
| 1111 | |
| 1112 | #endif |
| 1113 | |
| 1114 | /* |
| 1115 | * "id" is the POSIX thread ID. We use the |
| 1116 | * files pointer for this.. |
| 1117 | */ |
| 1118 | int filp_close(struct file *filp, fl_owner_t id) |
| 1119 | { |
Christoph Lameter | 45778ca | 2005-06-23 00:10:17 -0700 | [diff] [blame] | 1120 | int retval = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1121 | |
| 1122 | if (!file_count(filp)) { |
| 1123 | printk(KERN_ERR "VFS: Close: file count is 0\n"); |
Christoph Lameter | 45778ca | 2005-06-23 00:10:17 -0700 | [diff] [blame] | 1124 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1125 | } |
| 1126 | |
Al Viro | 72c2d53 | 2013-09-22 16:27:52 -0400 | [diff] [blame] | 1127 | if (filp->f_op->flush) |
Miklos Szeredi | 75e1fcc | 2006-06-23 02:05:12 -0700 | [diff] [blame] | 1128 | retval = filp->f_op->flush(filp, id); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1129 | |
Al Viro | 1abf0c7 | 2011-03-13 03:51:11 -0400 | [diff] [blame] | 1130 | if (likely(!(filp->f_mode & FMODE_PATH))) { |
| 1131 | dnotify_flush(filp, id); |
| 1132 | locks_remove_posix(filp, id); |
| 1133 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1134 | fput(filp); |
| 1135 | return retval; |
| 1136 | } |
| 1137 | |
| 1138 | EXPORT_SYMBOL(filp_close); |
| 1139 | |
| 1140 | /* |
| 1141 | * Careful here! We test whether the file pointer is NULL before |
| 1142 | * releasing the fd. This ensures that one clone task can't release |
| 1143 | * an fd while another clone is opening it. |
| 1144 | */ |
Heiko Carstens | ca013e9 | 2009-01-14 14:14:19 +0100 | [diff] [blame] | 1145 | SYSCALL_DEFINE1(close, unsigned int, fd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1146 | { |
Al Viro | 483ce1d | 2012-08-19 12:04:24 -0400 | [diff] [blame] | 1147 | int retval = __close_fd(current->files, fd); |
Ernie Petrides | ee731f4 | 2006-09-29 02:00:13 -0700 | [diff] [blame] | 1148 | |
| 1149 | /* can't restart close syscall because file table entry was cleared */ |
| 1150 | if (unlikely(retval == -ERESTARTSYS || |
| 1151 | retval == -ERESTARTNOINTR || |
| 1152 | retval == -ERESTARTNOHAND || |
| 1153 | retval == -ERESTART_RESTARTBLOCK)) |
| 1154 | retval = -EINTR; |
| 1155 | |
| 1156 | return retval; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1157 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1158 | EXPORT_SYMBOL(sys_close); |
| 1159 | |
| 1160 | /* |
| 1161 | * This routine simulates a hangup on the tty, to arrange that users |
| 1162 | * are given clean terminals at login time. |
| 1163 | */ |
Heiko Carstens | ca013e9 | 2009-01-14 14:14:19 +0100 | [diff] [blame] | 1164 | SYSCALL_DEFINE0(vhangup) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1165 | { |
| 1166 | if (capable(CAP_SYS_TTY_CONFIG)) { |
Alan Cox | 2cb5998 | 2008-10-13 10:40:30 +0100 | [diff] [blame] | 1167 | tty_vhangup_self(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1168 | return 0; |
| 1169 | } |
| 1170 | return -EPERM; |
| 1171 | } |
| 1172 | |
| 1173 | /* |
| 1174 | * Called when an inode is about to be open. |
| 1175 | * We use this to disallow opening large files on 32bit systems if |
| 1176 | * the caller didn't specify O_LARGEFILE. On 64bit systems we force |
| 1177 | * on this flag in sys_open. |
| 1178 | */ |
| 1179 | int generic_file_open(struct inode * inode, struct file * filp) |
| 1180 | { |
| 1181 | if (!(filp->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS) |
Alan Cox | a9c62a1 | 2007-10-16 23:30:22 -0700 | [diff] [blame] | 1182 | return -EOVERFLOW; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1183 | return 0; |
| 1184 | } |
| 1185 | |
| 1186 | EXPORT_SYMBOL(generic_file_open); |
| 1187 | |
| 1188 | /* |
| 1189 | * This is used by subsystems that don't want seekable |
Dmitry Torokhov | 06b1e10 | 2010-08-10 18:01:33 -0700 | [diff] [blame] | 1190 | * file descriptors. The function is not supposed to ever fail, the only |
| 1191 | * reason it returns an 'int' and not 'void' is so that it can be plugged |
| 1192 | * directly into file_operations structure. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1193 | */ |
| 1194 | int nonseekable_open(struct inode *inode, struct file *filp) |
| 1195 | { |
| 1196 | filp->f_mode &= ~(FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE); |
| 1197 | return 0; |
| 1198 | } |
| 1199 | |
| 1200 | EXPORT_SYMBOL(nonseekable_open); |