Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 1 | /* |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 2 | * arch/xtensa/kernel/signal.c |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 3 | * |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 4 | * Default platform functions. |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 5 | * |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 6 | * This file is subject to the terms and conditions of the GNU General Public |
| 7 | * License. See the file "COPYING" in the main directory of this archive |
| 8 | * for more details. |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 9 | * |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 10 | * Copyright (C) 2005, 2006 Tensilica Inc. |
| 11 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 12 | * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 13 | * |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 14 | * Chris Zankel <chris@zankel.net> |
| 15 | * Joe Taylor <joe@tensilica.com> |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 16 | */ |
| 17 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 18 | #include <linux/signal.h> |
| 19 | #include <linux/errno.h> |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 20 | #include <linux/ptrace.h> |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 21 | #include <linux/personality.h> |
Al Viro | a53bb24e | 2012-04-24 02:30:16 -0400 | [diff] [blame] | 22 | #include <linux/tracehook.h> |
Ingo Molnar | 68db0cf | 2017-02-08 18:51:37 +0100 | [diff] [blame] | 23 | #include <linux/sched/task_stack.h> |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 24 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 25 | #include <asm/ucontext.h> |
Linus Torvalds | 7c0f6ba | 2016-12-24 11:46:01 -0800 | [diff] [blame] | 26 | #include <linux/uaccess.h> |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 27 | #include <asm/cacheflush.h> |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 28 | #include <asm/coprocessor.h> |
| 29 | #include <asm/unistd.h> |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 30 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 31 | extern struct task_struct *coproc_owners[]; |
| 32 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 33 | struct rt_sigframe |
| 34 | { |
| 35 | struct siginfo info; |
| 36 | struct ucontext uc; |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 37 | struct { |
| 38 | xtregs_opt_t opt; |
| 39 | xtregs_user_t user; |
| 40 | #if XTENSA_HAVE_COPROCESSORS |
| 41 | xtregs_coprocessor_t cp; |
| 42 | #endif |
| 43 | } xtregs; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 44 | unsigned char retcode[6]; |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 45 | unsigned int window[4]; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 46 | }; |
| 47 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 48 | /* |
| 49 | * Flush register windows stored in pt_regs to stack. |
| 50 | * Returns 1 for errors. |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 51 | */ |
| 52 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 53 | int |
| 54 | flush_window_regs_user(struct pt_regs *regs) |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 55 | { |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 56 | const unsigned long ws = regs->windowstart; |
| 57 | const unsigned long wb = regs->windowbase; |
| 58 | unsigned long sp = 0; |
| 59 | unsigned long wm; |
| 60 | int err = 1; |
| 61 | int base; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 62 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 63 | /* Return if no other frames. */ |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 64 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 65 | if (regs->wmask == 1) |
| 66 | return 0; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 67 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 68 | /* Rotate windowmask and skip empty frames. */ |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 69 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 70 | wm = (ws >> wb) | (ws << (XCHAL_NUM_AREGS / 4 - wb)); |
| 71 | base = (XCHAL_NUM_AREGS / 4) - (regs->wmask >> 4); |
| 72 | |
| 73 | /* For call8 or call12 frames, we need the previous stack pointer. */ |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 74 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 75 | if ((regs->wmask & 2) == 0) |
| 76 | if (__get_user(sp, (int*)(regs->areg[base * 4 + 1] - 12))) |
| 77 | goto errout; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 78 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 79 | /* Spill frames to stack. */ |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 80 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 81 | while (base < XCHAL_NUM_AREGS / 4) { |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 82 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 83 | int m = (wm >> base); |
| 84 | int inc = 0; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 85 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 86 | /* Save registers a4..a7 (call8) or a4...a11 (call12) */ |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 87 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 88 | if (m & 2) { /* call4 */ |
| 89 | inc = 1; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 90 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 91 | } else if (m & 4) { /* call8 */ |
Max Filippov | 062b1c1 | 2015-01-27 01:15:10 +0300 | [diff] [blame] | 92 | if (copy_to_user(&SPILL_SLOT_CALL8(sp, 4), |
| 93 | ®s->areg[(base + 1) * 4], 16)) |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 94 | goto errout; |
| 95 | inc = 2; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 96 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 97 | } else if (m & 8) { /* call12 */ |
Max Filippov | 062b1c1 | 2015-01-27 01:15:10 +0300 | [diff] [blame] | 98 | if (copy_to_user(&SPILL_SLOT_CALL12(sp, 4), |
| 99 | ®s->areg[(base + 1) * 4], 32)) |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 100 | goto errout; |
| 101 | inc = 3; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 102 | } |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 103 | |
| 104 | /* Save current frame a0..a3 under next SP */ |
| 105 | |
| 106 | sp = regs->areg[((base + inc) * 4 + 1) % XCHAL_NUM_AREGS]; |
Max Filippov | 062b1c1 | 2015-01-27 01:15:10 +0300 | [diff] [blame] | 107 | if (copy_to_user(&SPILL_SLOT(sp, 0), ®s->areg[base * 4], 16)) |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 108 | goto errout; |
| 109 | |
| 110 | /* Get current stack pointer for next loop iteration. */ |
| 111 | |
| 112 | sp = regs->areg[base * 4 + 1]; |
| 113 | base += inc; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 114 | } |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 115 | |
Chris Zankel | 3befce8 | 2008-02-12 12:22:15 -0800 | [diff] [blame] | 116 | regs->wmask = 1; |
| 117 | regs->windowstart = 1 << wb; |
| 118 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 119 | return 0; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 120 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 121 | errout: |
| 122 | return err; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 123 | } |
| 124 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 125 | /* |
| 126 | * Note: We don't copy double exception 'regs', we have to finish double exc. |
| 127 | * first before we return to signal handler! This dbl.exc.handler might cause |
| 128 | * another double exception, but I think we are fine as the situation is the |
| 129 | * same as if we had returned to the signal handerl and got an interrupt |
| 130 | * immediately... |
| 131 | */ |
| 132 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 133 | static int |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 134 | setup_sigcontext(struct rt_sigframe __user *frame, struct pt_regs *regs) |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 135 | { |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 136 | struct sigcontext __user *sc = &frame->uc.uc_mcontext; |
| 137 | struct thread_info *ti = current_thread_info(); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 138 | int err = 0; |
| 139 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 140 | #define COPY(x) err |= __put_user(regs->x, &sc->sc_##x) |
| 141 | COPY(pc); |
| 142 | COPY(ps); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 143 | COPY(lbeg); |
| 144 | COPY(lend); |
| 145 | COPY(lcount); |
| 146 | COPY(sar); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 147 | #undef COPY |
| 148 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 149 | err |= flush_window_regs_user(regs); |
| 150 | err |= __copy_to_user (sc->sc_a, regs->areg, 16 * 4); |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 151 | err |= __put_user(0, &sc->sc_xtregs); |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 152 | |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 153 | if (err) |
| 154 | return err; |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 155 | |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 156 | #if XTENSA_HAVE_COPROCESSORS |
| 157 | coprocessor_flush_all(ti); |
| 158 | coprocessor_release_all(ti); |
| 159 | err |= __copy_to_user(&frame->xtregs.cp, &ti->xtregs_cp, |
| 160 | sizeof (frame->xtregs.cp)); |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 161 | #endif |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 162 | err |= __copy_to_user(&frame->xtregs.opt, ®s->xtregs_opt, |
| 163 | sizeof (xtregs_opt_t)); |
| 164 | err |= __copy_to_user(&frame->xtregs.user, &ti->xtregs_user, |
| 165 | sizeof (xtregs_user_t)); |
| 166 | |
| 167 | err |= __put_user(err ? NULL : &frame->xtregs, &sc->sc_xtregs); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 168 | |
| 169 | return err; |
| 170 | } |
| 171 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 172 | static int |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 173 | restore_sigcontext(struct pt_regs *regs, struct rt_sigframe __user *frame) |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 174 | { |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 175 | struct sigcontext __user *sc = &frame->uc.uc_mcontext; |
| 176 | struct thread_info *ti = current_thread_info(); |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 177 | unsigned int err = 0; |
| 178 | unsigned long ps; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 179 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 180 | #define COPY(x) err |= __get_user(regs->x, &sc->sc_##x) |
| 181 | COPY(pc); |
| 182 | COPY(lbeg); |
| 183 | COPY(lend); |
| 184 | COPY(lcount); |
| 185 | COPY(sar); |
| 186 | #undef COPY |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 187 | |
Max Filippov | 6a98698 | 2018-11-09 15:43:14 -0800 | [diff] [blame] | 188 | /* All registers were flushed to stack. Start with a pristine frame. */ |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 189 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 190 | regs->wmask = 1; |
| 191 | regs->windowbase = 0; |
| 192 | regs->windowstart = 1; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 193 | |
Max Filippov | 6a98698 | 2018-11-09 15:43:14 -0800 | [diff] [blame] | 194 | regs->syscall = NO_SYSCALL; /* disable syscall checks */ |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 195 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 196 | /* For PS, restore only PS.CALLINC. |
| 197 | * Assume that all other bits are either the same as for the signal |
| 198 | * handler, or the user mode value doesn't matter (e.g. PS.OWB). |
| 199 | */ |
| 200 | err |= __get_user(ps, &sc->sc_ps); |
| 201 | regs->ps = (regs->ps & ~PS_CALLINC_MASK) | (ps & PS_CALLINC_MASK); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 202 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 203 | /* Additional corruption checks */ |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 204 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 205 | if ((regs->lcount > 0) |
| 206 | && ((regs->lbeg > TASK_SIZE) || (regs->lend > TASK_SIZE)) ) |
| 207 | err = 1; |
| 208 | |
| 209 | err |= __copy_from_user(regs->areg, sc->sc_a, 16 * 4); |
| 210 | |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 211 | if (err) |
| 212 | return err; |
| 213 | |
Chris Zankel | c4c4594 | 2012-11-28 16:53:51 -0800 | [diff] [blame] | 214 | /* The signal handler may have used coprocessors in which |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 215 | * case they are still enabled. We disable them to force a |
| 216 | * reloading of the original task's CP state by the lazy |
| 217 | * context-switching mechanisms of CP exception handling. |
| 218 | * Also, we essentially discard any coprocessor state that the |
| 219 | * signal handler created. */ |
| 220 | |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 221 | #if XTENSA_HAVE_COPROCESSORS |
| 222 | coprocessor_release_all(ti); |
| 223 | err |= __copy_from_user(&ti->xtregs_cp, &frame->xtregs.cp, |
| 224 | sizeof (frame->xtregs.cp)); |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 225 | #endif |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 226 | err |= __copy_from_user(&ti->xtregs_user, &frame->xtregs.user, |
| 227 | sizeof (xtregs_user_t)); |
| 228 | err |= __copy_from_user(®s->xtregs_opt, &frame->xtregs.opt, |
| 229 | sizeof (xtregs_opt_t)); |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 230 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 231 | return err; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 232 | } |
| 233 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 234 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 235 | /* |
| 236 | * Do a signal return; undo the signal stack. |
| 237 | */ |
| 238 | |
Max Filippov | 9d9043f | 2019-11-29 01:25:20 -0800 | [diff] [blame] | 239 | asmlinkage long xtensa_rt_sigreturn(void) |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 240 | { |
Max Filippov | 9d9043f | 2019-11-29 01:25:20 -0800 | [diff] [blame] | 241 | struct pt_regs *regs = current_pt_regs(); |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 242 | struct rt_sigframe __user *frame; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 243 | sigset_t set; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 244 | int ret; |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 245 | |
Al Viro | 188f677 | 2012-04-22 03:35:28 -0400 | [diff] [blame] | 246 | /* Always make any pending restarted system calls return -EINTR */ |
Andy Lutomirski | f56141e | 2015-02-12 15:01:14 -0800 | [diff] [blame] | 247 | current->restart_block.fn = do_no_restart_syscall; |
Al Viro | 188f677 | 2012-04-22 03:35:28 -0400 | [diff] [blame] | 248 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 249 | if (regs->depc > 64) |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 250 | panic("rt_sigreturn in double exception!\n"); |
| 251 | |
| 252 | frame = (struct rt_sigframe __user *) regs->areg[1]; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 253 | |
Linus Torvalds | 96d4f26 | 2019-01-03 18:57:57 -0800 | [diff] [blame] | 254 | if (!access_ok(frame, sizeof(*frame))) |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 255 | goto badframe; |
| 256 | |
| 257 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) |
| 258 | goto badframe; |
| 259 | |
Matt Fleming | d12f7c4 | 2012-03-21 16:33:45 -0700 | [diff] [blame] | 260 | set_current_blocked(&set); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 261 | |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 262 | if (restore_sigcontext(regs, frame)) |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 263 | goto badframe; |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 264 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 265 | ret = regs->areg[2]; |
| 266 | |
Al Viro | 0430f2f | 2012-12-23 03:54:43 -0500 | [diff] [blame] | 267 | if (restore_altstack(&frame->uc.uc_stack)) |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 268 | goto badframe; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 269 | |
| 270 | return ret; |
| 271 | |
| 272 | badframe: |
Eric W. Biederman | 3cf5d07 | 2019-05-23 10:17:27 -0500 | [diff] [blame] | 273 | force_sig(SIGSEGV); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 274 | return 0; |
| 275 | } |
| 276 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 277 | |
| 278 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 279 | /* |
| 280 | * Set up a signal frame. |
| 281 | */ |
| 282 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 283 | static int |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 284 | gen_return_code(unsigned char *codemem) |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 285 | { |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 286 | int err = 0; |
| 287 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 288 | /* |
| 289 | * The 12-bit immediate is really split up within the 24-bit MOVI |
| 290 | * instruction. As long as the above system call numbers fit within |
| 291 | * 8-bits, the following code works fine. See the Xtensa ISA for |
| 292 | * details. |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 293 | */ |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 294 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 295 | #if __NR_rt_sigreturn > 255 |
| 296 | # error Generating the MOVI instruction below breaks! |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 297 | #endif |
| 298 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 299 | #ifdef __XTENSA_EB__ /* Big Endian version */ |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 300 | /* Generate instruction: MOVI a2, __NR_rt_sigreturn */ |
| 301 | err |= __put_user(0x22, &codemem[0]); |
| 302 | err |= __put_user(0x0a, &codemem[1]); |
| 303 | err |= __put_user(__NR_rt_sigreturn, &codemem[2]); |
| 304 | /* Generate instruction: SYSCALL */ |
| 305 | err |= __put_user(0x00, &codemem[3]); |
| 306 | err |= __put_user(0x05, &codemem[4]); |
| 307 | err |= __put_user(0x00, &codemem[5]); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 308 | |
| 309 | #elif defined __XTENSA_EL__ /* Little Endian version */ |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 310 | /* Generate instruction: MOVI a2, __NR_rt_sigreturn */ |
| 311 | err |= __put_user(0x22, &codemem[0]); |
| 312 | err |= __put_user(0xa0, &codemem[1]); |
| 313 | err |= __put_user(__NR_rt_sigreturn, &codemem[2]); |
| 314 | /* Generate instruction: SYSCALL */ |
| 315 | err |= __put_user(0x00, &codemem[3]); |
| 316 | err |= __put_user(0x50, &codemem[4]); |
| 317 | err |= __put_user(0x00, &codemem[5]); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 318 | #else |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 319 | # error Must use compiler for Xtensa processors. |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 320 | #endif |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 321 | |
| 322 | /* Flush generated code out of the data cache */ |
| 323 | |
Chris Zankel | 173d668 | 2006-12-10 02:18:48 -0800 | [diff] [blame] | 324 | if (err == 0) { |
| 325 | __invalidate_icache_range((unsigned long)codemem, 6UL); |
| 326 | __flush_invalidate_dcache_range((unsigned long)codemem, 6UL); |
| 327 | } |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 328 | |
| 329 | return err; |
| 330 | } |
| 331 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 332 | |
Richard Weinberger | 5bdb7611 | 2013-10-07 15:09:23 +0200 | [diff] [blame] | 333 | static int setup_frame(struct ksignal *ksig, sigset_t *set, |
| 334 | struct pt_regs *regs) |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 335 | { |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 336 | struct rt_sigframe *frame; |
Richard Weinberger | 5bdb7611 | 2013-10-07 15:09:23 +0200 | [diff] [blame] | 337 | int err = 0, sig = ksig->sig; |
Max Filippov | 09f8a6d | 2015-01-12 09:44:44 +0300 | [diff] [blame] | 338 | unsigned long sp, ra, tp, ps; |
| 339 | unsigned int base; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 340 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 341 | sp = regs->areg[1]; |
| 342 | |
Richard Weinberger | 5bdb7611 | 2013-10-07 15:09:23 +0200 | [diff] [blame] | 343 | if ((ksig->ka.sa.sa_flags & SA_ONSTACK) != 0 && sas_ss_flags(sp) == 0) { |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 344 | sp = current->sas_ss_sp + current->sas_ss_size; |
| 345 | } |
| 346 | |
| 347 | frame = (void *)((sp - sizeof(*frame)) & -16ul); |
| 348 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 349 | if (regs->depc > 64) |
| 350 | panic ("Double exception sys_sigreturn\n"); |
| 351 | |
Linus Torvalds | 96d4f26 | 2019-01-03 18:57:57 -0800 | [diff] [blame] | 352 | if (!access_ok(frame, sizeof(*frame))) { |
Richard Weinberger | 5bdb7611 | 2013-10-07 15:09:23 +0200 | [diff] [blame] | 353 | return -EFAULT; |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 354 | } |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 355 | |
Richard Weinberger | 5bdb7611 | 2013-10-07 15:09:23 +0200 | [diff] [blame] | 356 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) { |
| 357 | err |= copy_siginfo_to_user(&frame->info, &ksig->info); |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 358 | } |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 359 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 360 | /* Create the user context. */ |
| 361 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 362 | err |= __put_user(0, &frame->uc.uc_flags); |
| 363 | err |= __put_user(0, &frame->uc.uc_link); |
Al Viro | 0430f2f | 2012-12-23 03:54:43 -0500 | [diff] [blame] | 364 | err |= __save_altstack(&frame->uc.uc_stack, regs->areg[1]); |
Chris Zankel | c658eac | 2008-02-12 13:17:07 -0800 | [diff] [blame] | 365 | err |= setup_sigcontext(frame, regs); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 366 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); |
| 367 | |
Richard Weinberger | 5bdb7611 | 2013-10-07 15:09:23 +0200 | [diff] [blame] | 368 | if (ksig->ka.sa.sa_flags & SA_RESTORER) { |
| 369 | ra = (unsigned long)ksig->ka.sa.sa_restorer; |
Chris Zankel | 44c64e6 | 2008-01-11 11:44:17 -0800 | [diff] [blame] | 370 | } else { |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 371 | |
Chris Zankel | 44c64e6 | 2008-01-11 11:44:17 -0800 | [diff] [blame] | 372 | /* Create sys_rt_sigreturn syscall in stack frame */ |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 373 | |
Chris Zankel | 44c64e6 | 2008-01-11 11:44:17 -0800 | [diff] [blame] | 374 | err |= gen_return_code(frame->retcode); |
| 375 | |
| 376 | if (err) { |
Richard Weinberger | 5bdb7611 | 2013-10-07 15:09:23 +0200 | [diff] [blame] | 377 | return -EFAULT; |
Chris Zankel | 44c64e6 | 2008-01-11 11:44:17 -0800 | [diff] [blame] | 378 | } |
| 379 | ra = (unsigned long) frame->retcode; |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 380 | } |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 381 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 382 | /* |
| 383 | * Create signal handler execution context. |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 384 | * Return context not modified until this point. |
| 385 | */ |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 386 | |
Chris Zankel | c50842d | 2013-02-23 19:35:57 -0800 | [diff] [blame] | 387 | /* Set up registers for signal handler; preserve the threadptr */ |
| 388 | tp = regs->threadptr; |
Max Filippov | 09f8a6d | 2015-01-12 09:44:44 +0300 | [diff] [blame] | 389 | ps = regs->ps; |
Richard Weinberger | 5bdb7611 | 2013-10-07 15:09:23 +0200 | [diff] [blame] | 390 | start_thread(regs, (unsigned long) ksig->ka.sa.sa_handler, |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 391 | (unsigned long) frame); |
| 392 | |
Max Filippov | 09f8a6d | 2015-01-12 09:44:44 +0300 | [diff] [blame] | 393 | /* Set up a stack frame for a call4 if userspace uses windowed ABI */ |
| 394 | if (ps & PS_WOE_MASK) { |
| 395 | base = 4; |
| 396 | regs->areg[base] = |
| 397 | (((unsigned long) ra) & 0x3fffffff) | 0x40000000; |
| 398 | ps = (ps & ~(PS_CALLINC_MASK | PS_OWB_MASK)) | |
| 399 | (1 << PS_CALLINC_SHIFT); |
| 400 | } else { |
| 401 | base = 0; |
| 402 | regs->areg[base] = (unsigned long) ra; |
| 403 | } |
| 404 | regs->areg[base + 2] = (unsigned long) sig; |
| 405 | regs->areg[base + 3] = (unsigned long) &frame->info; |
| 406 | regs->areg[base + 4] = (unsigned long) &frame->uc; |
Chris Zankel | c50842d | 2013-02-23 19:35:57 -0800 | [diff] [blame] | 407 | regs->threadptr = tp; |
Max Filippov | 09f8a6d | 2015-01-12 09:44:44 +0300 | [diff] [blame] | 408 | regs->ps = ps; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 409 | |
Max Filippov | c130d3b | 2017-12-15 12:00:30 -0800 | [diff] [blame] | 410 | pr_debug("SIG rt deliver (%s:%d): signal=%d sp=%p pc=%08lx\n", |
| 411 | current->comm, current->pid, sig, frame, regs->pc); |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 412 | |
Matt Fleming | 3785006 | 2012-03-21 16:33:45 -0700 | [diff] [blame] | 413 | return 0; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 414 | } |
| 415 | |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 416 | /* |
| 417 | * Note that 'init' is a special process: it doesn't get signals it doesn't |
| 418 | * want to handle. Thus you cannot kill init even with a SIGKILL even by |
| 419 | * mistake. |
| 420 | * |
| 421 | * Note that we go through the signals twice: once to check the signals that |
| 422 | * the kernel can handle, and then we build all the user-level signal handling |
| 423 | * stack-frames in one go after that. |
| 424 | */ |
Al Viro | a53bb24e | 2012-04-24 02:30:16 -0400 | [diff] [blame] | 425 | static void do_signal(struct pt_regs *regs) |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 426 | { |
Richard Weinberger | 5bdb7611 | 2013-10-07 15:09:23 +0200 | [diff] [blame] | 427 | struct ksignal ksig; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 428 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 429 | task_pt_regs(current)->icountlevel = 0; |
| 430 | |
Richard Weinberger | 5bdb7611 | 2013-10-07 15:09:23 +0200 | [diff] [blame] | 431 | if (get_signal(&ksig)) { |
Paul Gortmaker | 9112a6b | 2012-04-18 16:17:13 -0400 | [diff] [blame] | 432 | int ret; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 433 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 434 | /* Are we from a system call? */ |
| 435 | |
Max Filippov | 6a98698 | 2018-11-09 15:43:14 -0800 | [diff] [blame] | 436 | if (regs->syscall != NO_SYSCALL) { |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 437 | |
| 438 | /* If so, check system call restarting.. */ |
| 439 | |
| 440 | switch (regs->areg[2]) { |
| 441 | case -ERESTARTNOHAND: |
| 442 | case -ERESTART_RESTARTBLOCK: |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 443 | regs->areg[2] = -EINTR; |
| 444 | break; |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 445 | |
| 446 | case -ERESTARTSYS: |
Richard Weinberger | 5bdb7611 | 2013-10-07 15:09:23 +0200 | [diff] [blame] | 447 | if (!(ksig.ka.sa.sa_flags & SA_RESTART)) { |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 448 | regs->areg[2] = -EINTR; |
| 449 | break; |
| 450 | } |
| 451 | /* fallthrough */ |
| 452 | case -ERESTARTNOINTR: |
| 453 | regs->areg[2] = regs->syscall; |
| 454 | regs->pc -= 3; |
| 455 | break; |
| 456 | |
| 457 | default: |
| 458 | /* nothing to do */ |
| 459 | if (regs->areg[2] != 0) |
| 460 | break; |
| 461 | } |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 462 | } |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 463 | |
| 464 | /* Whee! Actually deliver the signal. */ |
| 465 | /* Set up the stack frame */ |
Richard Weinberger | 5bdb7611 | 2013-10-07 15:09:23 +0200 | [diff] [blame] | 466 | ret = setup_frame(&ksig, sigmask_to_save(), regs); |
| 467 | signal_setup_done(ret, &ksig, 0); |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 468 | if (current->ptrace & PT_SINGLESTEP) |
| 469 | task_pt_regs(current)->icountlevel = 1; |
| 470 | |
Al Viro | 9ccc9c7 | 2012-04-22 00:59:07 -0400 | [diff] [blame] | 471 | return; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 472 | } |
| 473 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 474 | /* Did we come from a system call? */ |
Max Filippov | 6a98698 | 2018-11-09 15:43:14 -0800 | [diff] [blame] | 475 | if (regs->syscall != NO_SYSCALL) { |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 476 | /* Restart the system call - no handlers present */ |
| 477 | switch (regs->areg[2]) { |
| 478 | case -ERESTARTNOHAND: |
| 479 | case -ERESTARTSYS: |
| 480 | case -ERESTARTNOINTR: |
| 481 | regs->areg[2] = regs->syscall; |
| 482 | regs->pc -= 3; |
| 483 | break; |
| 484 | case -ERESTART_RESTARTBLOCK: |
| 485 | regs->areg[2] = __NR_restart_syscall; |
| 486 | regs->pc -= 3; |
| 487 | break; |
| 488 | } |
| 489 | } |
Al Viro | 9ccc9c7 | 2012-04-22 00:59:07 -0400 | [diff] [blame] | 490 | |
| 491 | /* If there's no signal to deliver, we just restore the saved mask. */ |
Al Viro | 51a7b44 | 2012-05-21 23:33:55 -0400 | [diff] [blame] | 492 | restore_saved_sigmask(); |
Al Viro | 9ccc9c7 | 2012-04-22 00:59:07 -0400 | [diff] [blame] | 493 | |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 494 | if (current->ptrace & PT_SINGLESTEP) |
| 495 | task_pt_regs(current)->icountlevel = 1; |
Al Viro | 9ccc9c7 | 2012-04-22 00:59:07 -0400 | [diff] [blame] | 496 | return; |
Chris Zankel | 5a0015d | 2005-06-23 22:01:16 -0700 | [diff] [blame] | 497 | } |
Chris Zankel | 29c4dfd | 2007-05-31 17:49:32 -0700 | [diff] [blame] | 498 | |
Al Viro | a53bb24e | 2012-04-24 02:30:16 -0400 | [diff] [blame] | 499 | void do_notify_resume(struct pt_regs *regs) |
| 500 | { |
Al Viro | a53bb24e | 2012-04-24 02:30:16 -0400 | [diff] [blame] | 501 | if (test_thread_flag(TIF_SIGPENDING)) |
| 502 | do_signal(regs); |
| 503 | |
Al Viro | a42c6de | 2012-05-23 14:44:37 -0400 | [diff] [blame] | 504 | if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) |
Al Viro | a53bb24e | 2012-04-24 02:30:16 -0400 | [diff] [blame] | 505 | tracehook_notify_resume(regs); |
Al Viro | a53bb24e | 2012-04-24 02:30:16 -0400 | [diff] [blame] | 506 | } |