blob: 76cee341507b7330b3955bf71a2aa4be887d351b [file] [log] [blame]
Chris Zankel5a0015d2005-06-23 22:01:16 -07001/*
Chris Zankel29c4dfd2007-05-31 17:49:32 -07002 * arch/xtensa/kernel/signal.c
Chris Zankel5a0015d2005-06-23 22:01:16 -07003 *
Chris Zankel29c4dfd2007-05-31 17:49:32 -07004 * Default platform functions.
Chris Zankel5a0015d2005-06-23 22:01:16 -07005 *
Chris Zankel29c4dfd2007-05-31 17:49:32 -07006 * 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 Zankel5a0015d2005-06-23 22:01:16 -07009 *
Chris Zankel29c4dfd2007-05-31 17:49:32 -070010 * 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 Zankel5a0015d2005-06-23 22:01:16 -070013 *
Chris Zankel29c4dfd2007-05-31 17:49:32 -070014 * Chris Zankel <chris@zankel.net>
15 * Joe Taylor <joe@tensilica.com>
Chris Zankel5a0015d2005-06-23 22:01:16 -070016 */
17
Chris Zankel5a0015d2005-06-23 22:01:16 -070018#include <linux/signal.h>
19#include <linux/errno.h>
Chris Zankel5a0015d2005-06-23 22:01:16 -070020#include <linux/ptrace.h>
Chris Zankel5a0015d2005-06-23 22:01:16 -070021#include <linux/personality.h>
Al Viroa53bb24e2012-04-24 02:30:16 -040022#include <linux/tracehook.h>
Ingo Molnar68db0cf2017-02-08 18:51:37 +010023#include <linux/sched/task_stack.h>
Chris Zankel29c4dfd2007-05-31 17:49:32 -070024
Chris Zankel5a0015d2005-06-23 22:01:16 -070025#include <asm/ucontext.h>
Linus Torvalds7c0f6ba2016-12-24 11:46:01 -080026#include <linux/uaccess.h>
Chris Zankel5a0015d2005-06-23 22:01:16 -070027#include <asm/cacheflush.h>
Chris Zankel29c4dfd2007-05-31 17:49:32 -070028#include <asm/coprocessor.h>
29#include <asm/unistd.h>
Chris Zankel5a0015d2005-06-23 22:01:16 -070030
Chris Zankel5a0015d2005-06-23 22:01:16 -070031extern struct task_struct *coproc_owners[];
32
Chris Zankel5a0015d2005-06-23 22:01:16 -070033struct rt_sigframe
34{
35 struct siginfo info;
36 struct ucontext uc;
Chris Zankelc658eac2008-02-12 13:17:07 -080037 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 Zankel5a0015d2005-06-23 22:01:16 -070044 unsigned char retcode[6];
Chris Zankel29c4dfd2007-05-31 17:49:32 -070045 unsigned int window[4];
Chris Zankel5a0015d2005-06-23 22:01:16 -070046};
47
Chris Zankel29c4dfd2007-05-31 17:49:32 -070048/*
49 * Flush register windows stored in pt_regs to stack.
50 * Returns 1 for errors.
Chris Zankel5a0015d2005-06-23 22:01:16 -070051 */
52
Chris Zankel29c4dfd2007-05-31 17:49:32 -070053int
54flush_window_regs_user(struct pt_regs *regs)
Chris Zankel5a0015d2005-06-23 22:01:16 -070055{
Chris Zankel29c4dfd2007-05-31 17:49:32 -070056 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 Zankel5a0015d2005-06-23 22:01:16 -070062
Chris Zankel29c4dfd2007-05-31 17:49:32 -070063 /* Return if no other frames. */
Chris Zankel5a0015d2005-06-23 22:01:16 -070064
Chris Zankel29c4dfd2007-05-31 17:49:32 -070065 if (regs->wmask == 1)
66 return 0;
Chris Zankel5a0015d2005-06-23 22:01:16 -070067
Chris Zankel29c4dfd2007-05-31 17:49:32 -070068 /* Rotate windowmask and skip empty frames. */
Chris Zankel5a0015d2005-06-23 22:01:16 -070069
Chris Zankel29c4dfd2007-05-31 17:49:32 -070070 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 Zankel5a0015d2005-06-23 22:01:16 -070074
Chris Zankel29c4dfd2007-05-31 17:49:32 -070075 if ((regs->wmask & 2) == 0)
76 if (__get_user(sp, (int*)(regs->areg[base * 4 + 1] - 12)))
77 goto errout;
Chris Zankel5a0015d2005-06-23 22:01:16 -070078
Chris Zankel29c4dfd2007-05-31 17:49:32 -070079 /* Spill frames to stack. */
Chris Zankel5a0015d2005-06-23 22:01:16 -070080
Chris Zankel29c4dfd2007-05-31 17:49:32 -070081 while (base < XCHAL_NUM_AREGS / 4) {
Chris Zankel5a0015d2005-06-23 22:01:16 -070082
Chris Zankel29c4dfd2007-05-31 17:49:32 -070083 int m = (wm >> base);
84 int inc = 0;
Chris Zankel5a0015d2005-06-23 22:01:16 -070085
Chris Zankel29c4dfd2007-05-31 17:49:32 -070086 /* Save registers a4..a7 (call8) or a4...a11 (call12) */
Chris Zankel5a0015d2005-06-23 22:01:16 -070087
Chris Zankel29c4dfd2007-05-31 17:49:32 -070088 if (m & 2) { /* call4 */
89 inc = 1;
Chris Zankel5a0015d2005-06-23 22:01:16 -070090
Chris Zankel29c4dfd2007-05-31 17:49:32 -070091 } else if (m & 4) { /* call8 */
Max Filippov062b1c12015-01-27 01:15:10 +030092 if (copy_to_user(&SPILL_SLOT_CALL8(sp, 4),
93 &regs->areg[(base + 1) * 4], 16))
Chris Zankel29c4dfd2007-05-31 17:49:32 -070094 goto errout;
95 inc = 2;
Chris Zankel5a0015d2005-06-23 22:01:16 -070096
Chris Zankel29c4dfd2007-05-31 17:49:32 -070097 } else if (m & 8) { /* call12 */
Max Filippov062b1c12015-01-27 01:15:10 +030098 if (copy_to_user(&SPILL_SLOT_CALL12(sp, 4),
99 &regs->areg[(base + 1) * 4], 32))
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700100 goto errout;
101 inc = 3;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700102 }
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700103
104 /* Save current frame a0..a3 under next SP */
105
106 sp = regs->areg[((base + inc) * 4 + 1) % XCHAL_NUM_AREGS];
Max Filippov062b1c12015-01-27 01:15:10 +0300107 if (copy_to_user(&SPILL_SLOT(sp, 0), &regs->areg[base * 4], 16))
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700108 goto errout;
109
110 /* Get current stack pointer for next loop iteration. */
111
112 sp = regs->areg[base * 4 + 1];
113 base += inc;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700114 }
Chris Zankel5a0015d2005-06-23 22:01:16 -0700115
Chris Zankel3befce82008-02-12 12:22:15 -0800116 regs->wmask = 1;
117 regs->windowstart = 1 << wb;
118
Chris Zankel5a0015d2005-06-23 22:01:16 -0700119 return 0;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700120
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700121errout:
122 return err;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700123}
124
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700125/*
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 Zankel5a0015d2005-06-23 22:01:16 -0700133static int
Chris Zankelc658eac2008-02-12 13:17:07 -0800134setup_sigcontext(struct rt_sigframe __user *frame, struct pt_regs *regs)
Chris Zankel5a0015d2005-06-23 22:01:16 -0700135{
Chris Zankelc658eac2008-02-12 13:17:07 -0800136 struct sigcontext __user *sc = &frame->uc.uc_mcontext;
137 struct thread_info *ti = current_thread_info();
Chris Zankel5a0015d2005-06-23 22:01:16 -0700138 int err = 0;
139
Chris Zankel5a0015d2005-06-23 22:01:16 -0700140#define COPY(x) err |= __put_user(regs->x, &sc->sc_##x)
141 COPY(pc);
142 COPY(ps);
Chris Zankel5a0015d2005-06-23 22:01:16 -0700143 COPY(lbeg);
144 COPY(lend);
145 COPY(lcount);
146 COPY(sar);
Chris Zankel5a0015d2005-06-23 22:01:16 -0700147#undef COPY
148
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700149 err |= flush_window_regs_user(regs);
150 err |= __copy_to_user (sc->sc_a, regs->areg, 16 * 4);
Chris Zankelc658eac2008-02-12 13:17:07 -0800151 err |= __put_user(0, &sc->sc_xtregs);
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700152
Chris Zankelc658eac2008-02-12 13:17:07 -0800153 if (err)
154 return err;
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700155
Chris Zankelc658eac2008-02-12 13:17:07 -0800156#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 Zankel29c4dfd2007-05-31 17:49:32 -0700161#endif
Chris Zankelc658eac2008-02-12 13:17:07 -0800162 err |= __copy_to_user(&frame->xtregs.opt, &regs->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 Zankel5a0015d2005-06-23 22:01:16 -0700168
169 return err;
170}
171
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700172static int
Chris Zankelc658eac2008-02-12 13:17:07 -0800173restore_sigcontext(struct pt_regs *regs, struct rt_sigframe __user *frame)
Chris Zankel5a0015d2005-06-23 22:01:16 -0700174{
Chris Zankelc658eac2008-02-12 13:17:07 -0800175 struct sigcontext __user *sc = &frame->uc.uc_mcontext;
176 struct thread_info *ti = current_thread_info();
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700177 unsigned int err = 0;
178 unsigned long ps;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700179
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700180#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 Zankel5a0015d2005-06-23 22:01:16 -0700187
Max Filippov6a986982018-11-09 15:43:14 -0800188 /* All registers were flushed to stack. Start with a pristine frame. */
Chris Zankel5a0015d2005-06-23 22:01:16 -0700189
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700190 regs->wmask = 1;
191 regs->windowbase = 0;
192 regs->windowstart = 1;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700193
Max Filippov6a986982018-11-09 15:43:14 -0800194 regs->syscall = NO_SYSCALL; /* disable syscall checks */
Chris Zankelc658eac2008-02-12 13:17:07 -0800195
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700196 /* 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 Zankel5a0015d2005-06-23 22:01:16 -0700202
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700203 /* Additional corruption checks */
Chris Zankel5a0015d2005-06-23 22:01:16 -0700204
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700205 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 Zankelc658eac2008-02-12 13:17:07 -0800211 if (err)
212 return err;
213
Chris Zankelc4c45942012-11-28 16:53:51 -0800214 /* The signal handler may have used coprocessors in which
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700215 * 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 Zankelc658eac2008-02-12 13:17:07 -0800221#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 Zankel29c4dfd2007-05-31 17:49:32 -0700225#endif
Chris Zankelc658eac2008-02-12 13:17:07 -0800226 err |= __copy_from_user(&ti->xtregs_user, &frame->xtregs.user,
227 sizeof (xtregs_user_t));
228 err |= __copy_from_user(&regs->xtregs_opt, &frame->xtregs.opt,
229 sizeof (xtregs_opt_t));
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700230
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700231 return err;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700232}
233
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700234
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700235/*
236 * Do a signal return; undo the signal stack.
237 */
238
Max Filippov9d9043f2019-11-29 01:25:20 -0800239asmlinkage long xtensa_rt_sigreturn(void)
Chris Zankel5a0015d2005-06-23 22:01:16 -0700240{
Max Filippov9d9043f2019-11-29 01:25:20 -0800241 struct pt_regs *regs = current_pt_regs();
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700242 struct rt_sigframe __user *frame;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700243 sigset_t set;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700244 int ret;
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700245
Al Viro188f6772012-04-22 03:35:28 -0400246 /* Always make any pending restarted system calls return -EINTR */
Andy Lutomirskif56141e2015-02-12 15:01:14 -0800247 current->restart_block.fn = do_no_restart_syscall;
Al Viro188f6772012-04-22 03:35:28 -0400248
Chris Zankel5a0015d2005-06-23 22:01:16 -0700249 if (regs->depc > 64)
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700250 panic("rt_sigreturn in double exception!\n");
251
252 frame = (struct rt_sigframe __user *) regs->areg[1];
Chris Zankel5a0015d2005-06-23 22:01:16 -0700253
Linus Torvalds96d4f262019-01-03 18:57:57 -0800254 if (!access_ok(frame, sizeof(*frame)))
Chris Zankel5a0015d2005-06-23 22:01:16 -0700255 goto badframe;
256
257 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
258 goto badframe;
259
Matt Flemingd12f7c42012-03-21 16:33:45 -0700260 set_current_blocked(&set);
Chris Zankel5a0015d2005-06-23 22:01:16 -0700261
Chris Zankelc658eac2008-02-12 13:17:07 -0800262 if (restore_sigcontext(regs, frame))
Chris Zankel5a0015d2005-06-23 22:01:16 -0700263 goto badframe;
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700264
Chris Zankel5a0015d2005-06-23 22:01:16 -0700265 ret = regs->areg[2];
266
Al Viro0430f2f2012-12-23 03:54:43 -0500267 if (restore_altstack(&frame->uc.uc_stack))
Chris Zankel5a0015d2005-06-23 22:01:16 -0700268 goto badframe;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700269
270 return ret;
271
272badframe:
Eric W. Biederman3cf5d072019-05-23 10:17:27 -0500273 force_sig(SIGSEGV);
Chris Zankel5a0015d2005-06-23 22:01:16 -0700274 return 0;
275}
276
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700277
278
Chris Zankel5a0015d2005-06-23 22:01:16 -0700279/*
280 * Set up a signal frame.
281 */
282
Chris Zankel5a0015d2005-06-23 22:01:16 -0700283static int
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700284gen_return_code(unsigned char *codemem)
Chris Zankel5a0015d2005-06-23 22:01:16 -0700285{
Chris Zankel5a0015d2005-06-23 22:01:16 -0700286 int err = 0;
287
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700288 /*
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 Zankel5a0015d2005-06-23 22:01:16 -0700293 */
Chris Zankel5a0015d2005-06-23 22:01:16 -0700294
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700295#if __NR_rt_sigreturn > 255
296# error Generating the MOVI instruction below breaks!
Chris Zankel5a0015d2005-06-23 22:01:16 -0700297#endif
298
Chris Zankel5a0015d2005-06-23 22:01:16 -0700299#ifdef __XTENSA_EB__ /* Big Endian version */
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700300 /* 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 Zankel5a0015d2005-06-23 22:01:16 -0700308
309#elif defined __XTENSA_EL__ /* Little Endian version */
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700310 /* 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 Zankel5a0015d2005-06-23 22:01:16 -0700318#else
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700319# error Must use compiler for Xtensa processors.
Chris Zankel5a0015d2005-06-23 22:01:16 -0700320#endif
Chris Zankel5a0015d2005-06-23 22:01:16 -0700321
322 /* Flush generated code out of the data cache */
323
Chris Zankel173d6682006-12-10 02:18:48 -0800324 if (err == 0) {
325 __invalidate_icache_range((unsigned long)codemem, 6UL);
326 __flush_invalidate_dcache_range((unsigned long)codemem, 6UL);
327 }
Chris Zankel5a0015d2005-06-23 22:01:16 -0700328
329 return err;
330}
331
Chris Zankel5a0015d2005-06-23 22:01:16 -0700332
Richard Weinberger5bdb76112013-10-07 15:09:23 +0200333static int setup_frame(struct ksignal *ksig, sigset_t *set,
334 struct pt_regs *regs)
Chris Zankel5a0015d2005-06-23 22:01:16 -0700335{
Chris Zankel5a0015d2005-06-23 22:01:16 -0700336 struct rt_sigframe *frame;
Richard Weinberger5bdb76112013-10-07 15:09:23 +0200337 int err = 0, sig = ksig->sig;
Max Filippov09f8a6d2015-01-12 09:44:44 +0300338 unsigned long sp, ra, tp, ps;
339 unsigned int base;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700340
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700341 sp = regs->areg[1];
342
Richard Weinberger5bdb76112013-10-07 15:09:23 +0200343 if ((ksig->ka.sa.sa_flags & SA_ONSTACK) != 0 && sas_ss_flags(sp) == 0) {
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700344 sp = current->sas_ss_sp + current->sas_ss_size;
345 }
346
347 frame = (void *)((sp - sizeof(*frame)) & -16ul);
348
Chris Zankel5a0015d2005-06-23 22:01:16 -0700349 if (regs->depc > 64)
350 panic ("Double exception sys_sigreturn\n");
351
Linus Torvalds96d4f262019-01-03 18:57:57 -0800352 if (!access_ok(frame, sizeof(*frame))) {
Richard Weinberger5bdb76112013-10-07 15:09:23 +0200353 return -EFAULT;
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700354 }
Chris Zankel5a0015d2005-06-23 22:01:16 -0700355
Richard Weinberger5bdb76112013-10-07 15:09:23 +0200356 if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
357 err |= copy_siginfo_to_user(&frame->info, &ksig->info);
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700358 }
Chris Zankel5a0015d2005-06-23 22:01:16 -0700359
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700360 /* Create the user context. */
361
Chris Zankel5a0015d2005-06-23 22:01:16 -0700362 err |= __put_user(0, &frame->uc.uc_flags);
363 err |= __put_user(0, &frame->uc.uc_link);
Al Viro0430f2f2012-12-23 03:54:43 -0500364 err |= __save_altstack(&frame->uc.uc_stack, regs->areg[1]);
Chris Zankelc658eac2008-02-12 13:17:07 -0800365 err |= setup_sigcontext(frame, regs);
Chris Zankel5a0015d2005-06-23 22:01:16 -0700366 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
367
Richard Weinberger5bdb76112013-10-07 15:09:23 +0200368 if (ksig->ka.sa.sa_flags & SA_RESTORER) {
369 ra = (unsigned long)ksig->ka.sa.sa_restorer;
Chris Zankel44c64e62008-01-11 11:44:17 -0800370 } else {
Chris Zankel5a0015d2005-06-23 22:01:16 -0700371
Chris Zankel44c64e62008-01-11 11:44:17 -0800372 /* Create sys_rt_sigreturn syscall in stack frame */
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700373
Chris Zankel44c64e62008-01-11 11:44:17 -0800374 err |= gen_return_code(frame->retcode);
375
376 if (err) {
Richard Weinberger5bdb76112013-10-07 15:09:23 +0200377 return -EFAULT;
Chris Zankel44c64e62008-01-11 11:44:17 -0800378 }
379 ra = (unsigned long) frame->retcode;
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700380 }
Chris Zankel5a0015d2005-06-23 22:01:16 -0700381
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700382 /*
383 * Create signal handler execution context.
Chris Zankel5a0015d2005-06-23 22:01:16 -0700384 * Return context not modified until this point.
385 */
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700386
Chris Zankelc50842d2013-02-23 19:35:57 -0800387 /* Set up registers for signal handler; preserve the threadptr */
388 tp = regs->threadptr;
Max Filippov09f8a6d2015-01-12 09:44:44 +0300389 ps = regs->ps;
Richard Weinberger5bdb76112013-10-07 15:09:23 +0200390 start_thread(regs, (unsigned long) ksig->ka.sa.sa_handler,
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700391 (unsigned long) frame);
392
Max Filippov09f8a6d2015-01-12 09:44:44 +0300393 /* 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 Zankelc50842d2013-02-23 19:35:57 -0800407 regs->threadptr = tp;
Max Filippov09f8a6d2015-01-12 09:44:44 +0300408 regs->ps = ps;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700409
Max Filippovc130d3b2017-12-15 12:00:30 -0800410 pr_debug("SIG rt deliver (%s:%d): signal=%d sp=%p pc=%08lx\n",
411 current->comm, current->pid, sig, frame, regs->pc);
Chris Zankel5a0015d2005-06-23 22:01:16 -0700412
Matt Fleming37850062012-03-21 16:33:45 -0700413 return 0;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700414}
415
Chris Zankel5a0015d2005-06-23 22:01:16 -0700416/*
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 Viroa53bb24e2012-04-24 02:30:16 -0400425static void do_signal(struct pt_regs *regs)
Chris Zankel5a0015d2005-06-23 22:01:16 -0700426{
Richard Weinberger5bdb76112013-10-07 15:09:23 +0200427 struct ksignal ksig;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700428
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700429 task_pt_regs(current)->icountlevel = 0;
430
Richard Weinberger5bdb76112013-10-07 15:09:23 +0200431 if (get_signal(&ksig)) {
Paul Gortmaker9112a6b2012-04-18 16:17:13 -0400432 int ret;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700433
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700434 /* Are we from a system call? */
435
Max Filippov6a986982018-11-09 15:43:14 -0800436 if (regs->syscall != NO_SYSCALL) {
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700437
438 /* If so, check system call restarting.. */
439
440 switch (regs->areg[2]) {
441 case -ERESTARTNOHAND:
442 case -ERESTART_RESTARTBLOCK:
Chris Zankel5a0015d2005-06-23 22:01:16 -0700443 regs->areg[2] = -EINTR;
444 break;
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700445
446 case -ERESTARTSYS:
Richard Weinberger5bdb76112013-10-07 15:09:23 +0200447 if (!(ksig.ka.sa.sa_flags & SA_RESTART)) {
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700448 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 Zankel5a0015d2005-06-23 22:01:16 -0700462 }
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700463
464 /* Whee! Actually deliver the signal. */
465 /* Set up the stack frame */
Richard Weinberger5bdb76112013-10-07 15:09:23 +0200466 ret = setup_frame(&ksig, sigmask_to_save(), regs);
467 signal_setup_done(ret, &ksig, 0);
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700468 if (current->ptrace & PT_SINGLESTEP)
469 task_pt_regs(current)->icountlevel = 1;
470
Al Viro9ccc9c72012-04-22 00:59:07 -0400471 return;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700472 }
473
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700474 /* Did we come from a system call? */
Max Filippov6a986982018-11-09 15:43:14 -0800475 if (regs->syscall != NO_SYSCALL) {
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700476 /* 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 Viro9ccc9c72012-04-22 00:59:07 -0400490
491 /* If there's no signal to deliver, we just restore the saved mask. */
Al Viro51a7b442012-05-21 23:33:55 -0400492 restore_saved_sigmask();
Al Viro9ccc9c72012-04-22 00:59:07 -0400493
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700494 if (current->ptrace & PT_SINGLESTEP)
495 task_pt_regs(current)->icountlevel = 1;
Al Viro9ccc9c72012-04-22 00:59:07 -0400496 return;
Chris Zankel5a0015d2005-06-23 22:01:16 -0700497}
Chris Zankel29c4dfd2007-05-31 17:49:32 -0700498
Al Viroa53bb24e2012-04-24 02:30:16 -0400499void do_notify_resume(struct pt_regs *regs)
500{
Al Viroa53bb24e2012-04-24 02:30:16 -0400501 if (test_thread_flag(TIF_SIGPENDING))
502 do_signal(regs);
503
Al Viroa42c6de2012-05-23 14:44:37 -0400504 if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME))
Al Viroa53bb24e2012-04-24 02:30:16 -0400505 tracehook_notify_resume(regs);
Al Viroa53bb24e2012-04-24 02:30:16 -0400506}