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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 | 2 | /* |
a53c8fab | 3 | * Copyright IBM Corp. 1999, 2006 |
1da177e4 LT |
4 | * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com) |
5 | * | |
6 | * Based on Intel version | |
7 | * | |
8 | * Copyright (C) 1991, 1992 Linus Torvalds | |
9 | * | |
10 | * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson | |
11 | */ | |
12 | ||
1da177e4 | 13 | #include <linux/sched.h> |
68db0cf1 | 14 | #include <linux/sched/task_stack.h> |
1da177e4 LT |
15 | #include <linux/mm.h> |
16 | #include <linux/smp.h> | |
1da177e4 LT |
17 | #include <linux/kernel.h> |
18 | #include <linux/signal.h> | |
19 | #include <linux/errno.h> | |
20 | #include <linux/wait.h> | |
21 | #include <linux/ptrace.h> | |
22 | #include <linux/unistd.h> | |
23 | #include <linux/stddef.h> | |
24 | #include <linux/tty.h> | |
25 | #include <linux/personality.h> | |
26 | #include <linux/binfmts.h> | |
753c4dd6 | 27 | #include <linux/tracehook.h> |
26689452 | 28 | #include <linux/syscalls.h> |
7757591a | 29 | #include <linux/compat.h> |
1da177e4 | 30 | #include <asm/ucontext.h> |
7c0f6ba6 | 31 | #include <linux/uaccess.h> |
1da177e4 | 32 | #include <asm/lowcore.h> |
a0616cde | 33 | #include <asm/switch_to.h> |
a806170e | 34 | #include "entry.h" |
1da177e4 | 35 | |
80703617 MS |
36 | /* |
37 | * Layout of an old-style signal-frame: | |
38 | * ----------------------------------------- | |
39 | * | save area (_SIGNAL_FRAMESIZE) | | |
40 | * ----------------------------------------- | |
41 | * | struct sigcontext | | |
42 | * | oldmask | | |
43 | * | _sigregs * | | |
44 | * ----------------------------------------- | |
45 | * | _sigregs with | | |
46 | * | _s390_regs_common | | |
47 | * | _s390_fp_regs | | |
48 | * ----------------------------------------- | |
49 | * | int signo | | |
50 | * ----------------------------------------- | |
51 | * | _sigregs_ext with | | |
52 | * | gprs_high 64 byte (opt) | | |
53 | * | vxrs_low 128 byte (opt) | | |
54 | * | vxrs_high 256 byte (opt) | | |
55 | * | reserved 128 byte (opt) | | |
56 | * ----------------------------------------- | |
57 | * | __u16 svc_insn | | |
58 | * ----------------------------------------- | |
59 | * The svc_insn entry with the sigreturn system call opcode does not | |
60 | * have a fixed position and moves if gprs_high or vxrs exist. | |
61 | * Future extensions will be added to _sigregs_ext. | |
62 | */ | |
63 | struct sigframe | |
1da177e4 LT |
64 | { |
65 | __u8 callee_used_stack[__SIGNAL_FRAMESIZE]; | |
66 | struct sigcontext sc; | |
67 | _sigregs sregs; | |
68 | int signo; | |
80703617 MS |
69 | _sigregs_ext sregs_ext; |
70 | __u16 svc_insn; /* Offset of svc_insn is NOT fixed! */ | |
71 | }; | |
1da177e4 | 72 | |
80703617 MS |
73 | /* |
74 | * Layout of an rt signal-frame: | |
75 | * ----------------------------------------- | |
76 | * | save area (_SIGNAL_FRAMESIZE) | | |
77 | * ----------------------------------------- | |
78 | * | svc __NR_rt_sigreturn 2 byte | | |
79 | * ----------------------------------------- | |
80 | * | struct siginfo | | |
81 | * ----------------------------------------- | |
82 | * | struct ucontext_extended with | | |
83 | * | unsigned long uc_flags | | |
84 | * | struct ucontext *uc_link | | |
85 | * | stack_t uc_stack | | |
86 | * | _sigregs uc_mcontext with | | |
87 | * | _s390_regs_common | | |
88 | * | _s390_fp_regs | | |
89 | * | sigset_t uc_sigmask | | |
90 | * | _sigregs_ext uc_mcontext_ext | | |
91 | * | gprs_high 64 byte (opt) | | |
92 | * | vxrs_low 128 byte (opt) | | |
93 | * | vxrs_high 256 byte (opt)| | |
94 | * | reserved 128 byte (opt) | | |
95 | * ----------------------------------------- | |
96 | * Future extensions will be added to _sigregs_ext. | |
97 | */ | |
98 | struct rt_sigframe | |
1da177e4 LT |
99 | { |
100 | __u8 callee_used_stack[__SIGNAL_FRAMESIZE]; | |
80703617 | 101 | __u16 svc_insn; |
1da177e4 | 102 | struct siginfo info; |
80703617 MS |
103 | struct ucontext_extended uc; |
104 | }; | |
105 | ||
106 | /* Store registers needed to create the signal frame */ | |
107 | static void store_sigregs(void) | |
108 | { | |
109 | save_access_regs(current->thread.acrs); | |
d0164ee2 | 110 | save_fpu_regs(); |
80703617 MS |
111 | } |
112 | ||
113 | /* Load registers after signal return */ | |
114 | static void load_sigregs(void) | |
115 | { | |
116 | restore_access_regs(current->thread.acrs); | |
80703617 | 117 | } |
1da177e4 | 118 | |
1da177e4 LT |
119 | /* Returns non-zero on fault. */ |
120 | static int save_sigregs(struct pt_regs *regs, _sigregs __user *sregs) | |
121 | { | |
6837a8c3 GS |
122 | _sigregs user_sregs; |
123 | ||
1da177e4 LT |
124 | /* Copy a 'clean' PSW mask to the user to avoid leaking |
125 | information about whether PER is currently on. */ | |
e258d719 | 126 | user_sregs.regs.psw.mask = PSW_USER_BITS | |
5ebf250d | 127 | (regs->psw.mask & (PSW_MASK_USER | PSW_MASK_RI)); |
b05e3703 MS |
128 | user_sregs.regs.psw.addr = regs->psw.addr; |
129 | memcpy(&user_sregs.regs.gprs, ®s->gprs, sizeof(sregs->regs.gprs)); | |
6837a8c3 | 130 | memcpy(&user_sregs.regs.acrs, current->thread.acrs, |
4725c860 | 131 | sizeof(user_sregs.regs.acrs)); |
904818e2 | 132 | fpregs_store(&user_sregs.fpregs, ¤t->thread.fpu); |
f8544ec4 HC |
133 | if (__copy_to_user(sregs, &user_sregs, sizeof(_sigregs))) |
134 | return -EFAULT; | |
135 | return 0; | |
1da177e4 LT |
136 | } |
137 | ||
1da177e4 LT |
138 | static int restore_sigregs(struct pt_regs *regs, _sigregs __user *sregs) |
139 | { | |
6837a8c3 | 140 | _sigregs user_sregs; |
1da177e4 LT |
141 | |
142 | /* Alwys make any pending restarted system call return -EINTR */ | |
f56141e3 | 143 | current->restart_block.fn = do_no_restart_syscall; |
1da177e4 | 144 | |
4725c860 | 145 | if (__copy_from_user(&user_sregs, sregs, sizeof(user_sregs))) |
f8544ec4 | 146 | return -EFAULT; |
4725c860 | 147 | |
5ebf250d HC |
148 | if (!is_ri_task(current) && (user_sregs.regs.psw.mask & PSW_MASK_RI)) |
149 | return -EINVAL; | |
150 | ||
4084eb77 HB |
151 | /* Test the floating-point-control word. */ |
152 | if (test_fp_ctl(user_sregs.fpregs.fpc)) | |
4725c860 MS |
153 | return -EINVAL; |
154 | ||
e258d719 | 155 | /* Use regs->psw.mask instead of PSW_USER_BITS to preserve PER bit. */ |
aa7e04b3 | 156 | regs->psw.mask = (regs->psw.mask & ~(PSW_MASK_USER | PSW_MASK_RI)) | |
5ebf250d | 157 | (user_sregs.regs.psw.mask & (PSW_MASK_USER | PSW_MASK_RI)); |
fa968ee2 | 158 | /* Check for invalid user address space control. */ |
e258d719 MS |
159 | if ((regs->psw.mask & PSW_MASK_ASC) == PSW_ASC_HOME) |
160 | regs->psw.mask = PSW_ASC_PRIMARY | | |
fa968ee2 | 161 | (regs->psw.mask & ~PSW_MASK_ASC); |
d4e81b35 MS |
162 | /* Check for invalid amode */ |
163 | if (regs->psw.mask & PSW_MASK_EA) | |
164 | regs->psw.mask |= PSW_MASK_BA; | |
165 | regs->psw.addr = user_sregs.regs.psw.addr; | |
b05e3703 | 166 | memcpy(®s->gprs, &user_sregs.regs.gprs, sizeof(sregs->regs.gprs)); |
6837a8c3 | 167 | memcpy(¤t->thread.acrs, &user_sregs.regs.acrs, |
4725c860 | 168 | sizeof(current->thread.acrs)); |
1da177e4 | 169 | |
904818e2 | 170 | fpregs_load(&user_sregs.fpregs, ¤t->thread.fpu); |
1da177e4 | 171 | |
d3a73acb | 172 | clear_pt_regs_flag(regs, PIF_SYSCALL); /* No longer in a system call */ |
1da177e4 LT |
173 | return 0; |
174 | } | |
175 | ||
80703617 MS |
176 | /* Returns non-zero on fault. */ |
177 | static int save_sigregs_ext(struct pt_regs *regs, | |
178 | _sigregs_ext __user *sregs_ext) | |
179 | { | |
80703617 MS |
180 | __u64 vxrs[__NUM_VXRS_LOW]; |
181 | int i; | |
182 | ||
183 | /* Save vector registers to signal stack */ | |
b5510d9b | 184 | if (MACHINE_HAS_VX) { |
80703617 | 185 | for (i = 0; i < __NUM_VXRS_LOW; i++) |
904818e2 | 186 | vxrs[i] = *((__u64 *)(current->thread.fpu.vxrs + i) + 1); |
80703617 MS |
187 | if (__copy_to_user(&sregs_ext->vxrs_low, vxrs, |
188 | sizeof(sregs_ext->vxrs_low)) || | |
189 | __copy_to_user(&sregs_ext->vxrs_high, | |
904818e2 | 190 | current->thread.fpu.vxrs + __NUM_VXRS_LOW, |
80703617 MS |
191 | sizeof(sregs_ext->vxrs_high))) |
192 | return -EFAULT; | |
193 | } | |
80703617 MS |
194 | return 0; |
195 | } | |
196 | ||
197 | static int restore_sigregs_ext(struct pt_regs *regs, | |
198 | _sigregs_ext __user *sregs_ext) | |
199 | { | |
80703617 MS |
200 | __u64 vxrs[__NUM_VXRS_LOW]; |
201 | int i; | |
202 | ||
203 | /* Restore vector registers from signal stack */ | |
b5510d9b | 204 | if (MACHINE_HAS_VX) { |
80703617 MS |
205 | if (__copy_from_user(vxrs, &sregs_ext->vxrs_low, |
206 | sizeof(sregs_ext->vxrs_low)) || | |
904818e2 | 207 | __copy_from_user(current->thread.fpu.vxrs + __NUM_VXRS_LOW, |
80703617 MS |
208 | &sregs_ext->vxrs_high, |
209 | sizeof(sregs_ext->vxrs_high))) | |
210 | return -EFAULT; | |
211 | for (i = 0; i < __NUM_VXRS_LOW; i++) | |
904818e2 | 212 | *((__u64 *)(current->thread.fpu.vxrs + i) + 1) = vxrs[i]; |
80703617 | 213 | } |
80703617 MS |
214 | return 0; |
215 | } | |
216 | ||
26689452 | 217 | SYSCALL_DEFINE0(sigreturn) |
1da177e4 | 218 | { |
03ff9a23 | 219 | struct pt_regs *regs = task_pt_regs(current); |
80703617 MS |
220 | struct sigframe __user *frame = |
221 | (struct sigframe __user *) regs->gprs[15]; | |
1da177e4 LT |
222 | sigset_t set; |
223 | ||
1da177e4 LT |
224 | if (__copy_from_user(&set.sig, &frame->sc.oldmask, _SIGMASK_COPY_SIZE)) |
225 | goto badframe; | |
391c62fe | 226 | set_current_blocked(&set); |
d0164ee2 | 227 | save_fpu_regs(); |
1da177e4 LT |
228 | if (restore_sigregs(regs, &frame->sregs)) |
229 | goto badframe; | |
80703617 MS |
230 | if (restore_sigregs_ext(regs, &frame->sregs_ext)) |
231 | goto badframe; | |
232 | load_sigregs(); | |
1da177e4 | 233 | return regs->gprs[2]; |
1da177e4 LT |
234 | badframe: |
235 | force_sig(SIGSEGV, current); | |
236 | return 0; | |
237 | } | |
238 | ||
26689452 | 239 | SYSCALL_DEFINE0(rt_sigreturn) |
1da177e4 | 240 | { |
03ff9a23 | 241 | struct pt_regs *regs = task_pt_regs(current); |
80703617 MS |
242 | struct rt_sigframe __user *frame = |
243 | (struct rt_sigframe __user *)regs->gprs[15]; | |
1da177e4 LT |
244 | sigset_t set; |
245 | ||
1da177e4 LT |
246 | if (__copy_from_user(&set.sig, &frame->uc.uc_sigmask, sizeof(set))) |
247 | goto badframe; | |
391c62fe | 248 | set_current_blocked(&set); |
80703617 MS |
249 | if (restore_altstack(&frame->uc.uc_stack)) |
250 | goto badframe; | |
d0164ee2 | 251 | save_fpu_regs(); |
1da177e4 LT |
252 | if (restore_sigregs(regs, &frame->uc.uc_mcontext)) |
253 | goto badframe; | |
80703617 | 254 | if (restore_sigregs_ext(regs, &frame->uc.uc_mcontext_ext)) |
4e3df37e | 255 | goto badframe; |
80703617 | 256 | load_sigregs(); |
1da177e4 | 257 | return regs->gprs[2]; |
1da177e4 LT |
258 | badframe: |
259 | force_sig(SIGSEGV, current); | |
260 | return 0; | |
261 | } | |
262 | ||
1da177e4 LT |
263 | /* |
264 | * Determine which stack to use.. | |
265 | */ | |
266 | static inline void __user * | |
267 | get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size) | |
268 | { | |
269 | unsigned long sp; | |
270 | ||
271 | /* Default to using normal stack */ | |
272 | sp = regs->gprs[15]; | |
273 | ||
de553438 HC |
274 | /* Overflow on alternate signal stack gives SIGSEGV. */ |
275 | if (on_sig_stack(sp) && !on_sig_stack((sp - frame_size) & -8UL)) | |
276 | return (void __user *) -1UL; | |
277 | ||
1da177e4 LT |
278 | /* This is the X/Open sanctioned signal stack switching. */ |
279 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
280 | if (! sas_ss_flags(sp)) | |
281 | sp = current->sas_ss_sp + current->sas_ss_size; | |
282 | } | |
283 | ||
1da177e4 LT |
284 | return (void __user *)((sp - frame_size) & -8ul); |
285 | } | |
286 | ||
54dfe5dd HC |
287 | static int setup_frame(int sig, struct k_sigaction *ka, |
288 | sigset_t *set, struct pt_regs * regs) | |
1da177e4 | 289 | { |
80703617 MS |
290 | struct sigframe __user *frame; |
291 | struct sigcontext sc; | |
292 | unsigned long restorer; | |
293 | size_t frame_size; | |
294 | ||
295 | /* | |
296 | * gprs_high are only present for a 31-bit task running on | |
297 | * a 64-bit kernel (see compat_signal.c) but the space for | |
298 | * gprs_high need to be allocated if vector registers are | |
299 | * included in the signal frame on a 31-bit system. | |
300 | */ | |
301 | frame_size = sizeof(*frame) - sizeof(frame->sregs_ext); | |
302 | if (MACHINE_HAS_VX) | |
303 | frame_size += sizeof(frame->sregs_ext); | |
304 | frame = get_sigframe(ka, regs, frame_size); | |
de553438 | 305 | if (frame == (void __user *) -1UL) |
067bf2d4 | 306 | return -EFAULT; |
de553438 | 307 | |
80703617 MS |
308 | /* Set up backchain. */ |
309 | if (__put_user(regs->gprs[15], (addr_t __user *) frame)) | |
067bf2d4 | 310 | return -EFAULT; |
1da177e4 | 311 | |
80703617 MS |
312 | /* Create struct sigcontext on the signal stack */ |
313 | memcpy(&sc.oldmask, &set->sig, _SIGMASK_COPY_SIZE); | |
314 | sc.sregs = (_sigregs __user __force *) &frame->sregs; | |
315 | if (__copy_to_user(&frame->sc, &sc, sizeof(frame->sc))) | |
316 | return -EFAULT; | |
317 | ||
318 | /* Store registers needed to create the signal frame */ | |
319 | store_sigregs(); | |
320 | ||
321 | /* Create _sigregs on the signal stack */ | |
1da177e4 | 322 | if (save_sigregs(regs, &frame->sregs)) |
067bf2d4 | 323 | return -EFAULT; |
80703617 MS |
324 | |
325 | /* Place signal number on stack to allow backtrace from handler. */ | |
326 | if (__put_user(regs->gprs[2], (int __user *) &frame->signo)) | |
327 | return -EFAULT; | |
328 | ||
329 | /* Create _sigregs_ext on the signal stack */ | |
330 | if (save_sigregs_ext(regs, &frame->sregs_ext)) | |
067bf2d4 | 331 | return -EFAULT; |
1da177e4 LT |
332 | |
333 | /* Set up to return from userspace. If provided, use a stub | |
334 | already in userspace. */ | |
335 | if (ka->sa.sa_flags & SA_RESTORER) { | |
fecc868a | 336 | restorer = (unsigned long) ka->sa.sa_restorer; |
1da177e4 | 337 | } else { |
80703617 | 338 | /* Signal frame without vector registers are short ! */ |
37d2cd9d | 339 | __u16 __user *svc = (void __user *) frame + frame_size - 2; |
80703617 | 340 | if (__put_user(S390_SYSCALL_OPCODE | __NR_sigreturn, svc)) |
067bf2d4 | 341 | return -EFAULT; |
fecc868a | 342 | restorer = (unsigned long) svc; |
1da177e4 LT |
343 | } |
344 | ||
1da177e4 | 345 | /* Set up registers for signal handler */ |
80703617 | 346 | regs->gprs[14] = restorer; |
1da177e4 | 347 | regs->gprs[15] = (unsigned long) frame; |
fa968ee2 MS |
348 | /* Force default amode and default user address space control. */ |
349 | regs->psw.mask = PSW_MASK_EA | PSW_MASK_BA | | |
e258d719 | 350 | (PSW_USER_BITS & PSW_MASK_ASC) | |
fa968ee2 | 351 | (regs->psw.mask & ~PSW_MASK_ASC); |
fecc868a | 352 | regs->psw.addr = (unsigned long) ka->sa.sa_handler; |
1da177e4 | 353 | |
6a32591a | 354 | regs->gprs[2] = sig; |
1da177e4 LT |
355 | regs->gprs[3] = (unsigned long) &frame->sc; |
356 | ||
357 | /* We forgot to include these in the sigcontext. | |
358 | To avoid breaking binary compatibility, they are passed as args. */ | |
aa33c8cb MS |
359 | if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL || |
360 | sig == SIGTRAP || sig == SIGFPE) { | |
361 | /* set extra registers only for synchronous signals */ | |
362 | regs->gprs[4] = regs->int_code & 127; | |
363 | regs->gprs[5] = regs->int_parm_long; | |
ef280c85 | 364 | regs->gprs[6] = current->thread.last_break; |
aa33c8cb | 365 | } |
54dfe5dd | 366 | return 0; |
1da177e4 LT |
367 | } |
368 | ||
067bf2d4 RW |
369 | static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, |
370 | struct pt_regs *regs) | |
1da177e4 | 371 | { |
80703617 MS |
372 | struct rt_sigframe __user *frame; |
373 | unsigned long uc_flags, restorer; | |
374 | size_t frame_size; | |
375 | ||
376 | frame_size = sizeof(struct rt_sigframe) - sizeof(_sigregs_ext); | |
377 | /* | |
378 | * gprs_high are only present for a 31-bit task running on | |
379 | * a 64-bit kernel (see compat_signal.c) but the space for | |
380 | * gprs_high need to be allocated if vector registers are | |
381 | * included in the signal frame on a 31-bit system. | |
382 | */ | |
383 | uc_flags = 0; | |
80703617 MS |
384 | if (MACHINE_HAS_VX) { |
385 | frame_size += sizeof(_sigregs_ext); | |
b5510d9b | 386 | uc_flags |= UC_VXRS; |
80703617 | 387 | } |
80703617 | 388 | frame = get_sigframe(&ksig->ka, regs, frame_size); |
de553438 | 389 | if (frame == (void __user *) -1UL) |
067bf2d4 | 390 | return -EFAULT; |
de553438 | 391 | |
80703617 MS |
392 | /* Set up backchain. */ |
393 | if (__put_user(regs->gprs[15], (addr_t __user *) frame)) | |
067bf2d4 | 394 | return -EFAULT; |
1da177e4 LT |
395 | |
396 | /* Set up to return from userspace. If provided, use a stub | |
397 | already in userspace. */ | |
067bf2d4 | 398 | if (ksig->ka.sa.sa_flags & SA_RESTORER) { |
fecc868a | 399 | restorer = (unsigned long) ksig->ka.sa.sa_restorer; |
1da177e4 | 400 | } else { |
80703617 MS |
401 | __u16 __user *svc = &frame->svc_insn; |
402 | if (__put_user(S390_SYSCALL_OPCODE | __NR_rt_sigreturn, svc)) | |
067bf2d4 | 403 | return -EFAULT; |
fecc868a | 404 | restorer = (unsigned long) svc; |
1da177e4 LT |
405 | } |
406 | ||
80703617 MS |
407 | /* Create siginfo on the signal stack */ |
408 | if (copy_siginfo_to_user(&frame->info, &ksig->info)) | |
409 | return -EFAULT; | |
410 | ||
411 | /* Store registers needed to create the signal frame */ | |
412 | store_sigregs(); | |
413 | ||
414 | /* Create ucontext on the signal stack. */ | |
415 | if (__put_user(uc_flags, &frame->uc.uc_flags) || | |
416 | __put_user(NULL, &frame->uc.uc_link) || | |
417 | __save_altstack(&frame->uc.uc_stack, regs->gprs[15]) || | |
418 | save_sigregs(regs, &frame->uc.uc_mcontext) || | |
419 | __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)) || | |
420 | save_sigregs_ext(regs, &frame->uc.uc_mcontext_ext)) | |
067bf2d4 | 421 | return -EFAULT; |
1da177e4 LT |
422 | |
423 | /* Set up registers for signal handler */ | |
80703617 | 424 | regs->gprs[14] = restorer; |
1da177e4 | 425 | regs->gprs[15] = (unsigned long) frame; |
fa968ee2 MS |
426 | /* Force default amode and default user address space control. */ |
427 | regs->psw.mask = PSW_MASK_EA | PSW_MASK_BA | | |
e258d719 | 428 | (PSW_USER_BITS & PSW_MASK_ASC) | |
fa968ee2 | 429 | (regs->psw.mask & ~PSW_MASK_ASC); |
fecc868a | 430 | regs->psw.addr = (unsigned long) ksig->ka.sa.sa_handler; |
1da177e4 | 431 | |
6a32591a | 432 | regs->gprs[2] = ksig->sig; |
1da177e4 LT |
433 | regs->gprs[3] = (unsigned long) &frame->info; |
434 | regs->gprs[4] = (unsigned long) &frame->uc; | |
ef280c85 | 435 | regs->gprs[5] = current->thread.last_break; |
54dfe5dd | 436 | return 0; |
1da177e4 LT |
437 | } |
438 | ||
067bf2d4 RW |
439 | static void handle_signal(struct ksignal *ksig, sigset_t *oldset, |
440 | struct pt_regs *regs) | |
1da177e4 | 441 | { |
54dfe5dd HC |
442 | int ret; |
443 | ||
1da177e4 | 444 | /* Set up the stack frame */ |
067bf2d4 RW |
445 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) |
446 | ret = setup_rt_frame(ksig, oldset, regs); | |
1da177e4 | 447 | else |
067bf2d4 RW |
448 | ret = setup_frame(ksig->sig, &ksig->ka, oldset, regs); |
449 | ||
450 | signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLE_STEP)); | |
1da177e4 LT |
451 | } |
452 | ||
453 | /* | |
454 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
455 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
456 | * mistake. | |
457 | * | |
458 | * Note that we go through the signals twice: once to check the signals that | |
459 | * the kernel can handle, and then we build all the user-level signal handling | |
460 | * stack-frames in one go after that. | |
461 | */ | |
54dfe5dd | 462 | void do_signal(struct pt_regs *regs) |
1da177e4 | 463 | { |
067bf2d4 | 464 | struct ksignal ksig; |
b7f9a11a | 465 | sigset_t *oldset = sigmask_to_save(); |
1da177e4 | 466 | |
20b40a79 MS |
467 | /* |
468 | * Get signal to deliver. When running under ptrace, at this point | |
469 | * the debugger may change all our registers, including the system | |
470 | * call information. | |
471 | */ | |
f8fc82b4 | 472 | current->thread.system_call = |
d3a73acb | 473 | test_pt_regs_flag(regs, PIF_SYSCALL) ? regs->int_code : 0; |
1da177e4 | 474 | |
067bf2d4 | 475 | if (get_signal(&ksig)) { |
1da177e4 | 476 | /* Whee! Actually deliver the signal. */ |
f8fc82b4 MS |
477 | if (current->thread.system_call) { |
478 | regs->int_code = current->thread.system_call; | |
20b40a79 MS |
479 | /* Check for system call restarting. */ |
480 | switch (regs->gprs[2]) { | |
481 | case -ERESTART_RESTARTBLOCK: | |
482 | case -ERESTARTNOHAND: | |
483 | regs->gprs[2] = -EINTR; | |
484 | break; | |
485 | case -ERESTARTSYS: | |
067bf2d4 | 486 | if (!(ksig.ka.sa.sa_flags & SA_RESTART)) { |
20b40a79 MS |
487 | regs->gprs[2] = -EINTR; |
488 | break; | |
489 | } | |
490 | /* fallthrough */ | |
491 | case -ERESTARTNOINTR: | |
492 | regs->gprs[2] = regs->orig_gpr2; | |
ccf45caf MS |
493 | regs->psw.addr = |
494 | __rewind_psw(regs->psw, | |
aa33c8cb | 495 | regs->int_code >> 16); |
20b40a79 MS |
496 | break; |
497 | } | |
20b40a79 | 498 | } |
d9ae6772 | 499 | /* No longer in a system call */ |
d3a73acb | 500 | clear_pt_regs_flag(regs, PIF_SYSCALL); |
20b40a79 | 501 | |
a610d6e6 | 502 | if (is_compat_task()) |
067bf2d4 | 503 | handle_signal32(&ksig, oldset, regs); |
a610d6e6 | 504 | else |
067bf2d4 | 505 | handle_signal(&ksig, oldset, regs); |
54dfe5dd HC |
506 | return; |
507 | } | |
508 | ||
20b40a79 | 509 | /* No handlers present - check for system call restart */ |
d3a73acb | 510 | clear_pt_regs_flag(regs, PIF_SYSCALL); |
f8fc82b4 MS |
511 | if (current->thread.system_call) { |
512 | regs->int_code = current->thread.system_call; | |
20b40a79 MS |
513 | switch (regs->gprs[2]) { |
514 | case -ERESTART_RESTARTBLOCK: | |
515 | /* Restart with sys_restart_syscall */ | |
aa33c8cb | 516 | regs->int_code = __NR_restart_syscall; |
20b40a79 MS |
517 | /* fallthrough */ |
518 | case -ERESTARTNOHAND: | |
519 | case -ERESTARTSYS: | |
520 | case -ERESTARTNOINTR: | |
521 | /* Restart system call with magic TIF bit. */ | |
522 | regs->gprs[2] = regs->orig_gpr2; | |
d3a73acb | 523 | set_pt_regs_flag(regs, PIF_SYSCALL); |
39efd4ec | 524 | if (test_thread_flag(TIF_SINGLE_STEP)) |
d3a73acb | 525 | clear_pt_regs_flag(regs, PIF_PER_TRAP); |
b6ef5bb3 | 526 | break; |
20b40a79 MS |
527 | } |
528 | } | |
529 | ||
54dfe5dd HC |
530 | /* |
531 | * If there's no signal to deliver, we just put the saved sigmask back. | |
532 | */ | |
51a7b448 | 533 | restore_saved_sigmask(); |
1da177e4 | 534 | } |
753c4dd6 MS |
535 | |
536 | void do_notify_resume(struct pt_regs *regs) | |
537 | { | |
538 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
539 | tracehook_notify_resume(regs); | |
540 | } |