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1/*
2 * linux/arch/x86_64/ia32/ia32_signal.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 *
6 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
7 * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes
8 * 2000-12-* x86-64 compatibility mode signal handling by Andi Kleen
9 */
10
11#include <linux/sched.h>
12#include <linux/mm.h>
13#include <linux/smp.h>
14#include <linux/kernel.h>
15#include <linux/errno.h>
16#include <linux/wait.h>
17#include <linux/unistd.h>
18#include <linux/stddef.h>
19#include <linux/personality.h>
20#include <linux/compat.h>
21#include <linux/binfmts.h>
22#include <asm/ucontext.h>
23#include <asm/uaccess.h>
24#include <asm/fpu/internal.h>
25#include <asm/fpu/signal.h>
26#include <asm/ptrace.h>
27#include <asm/ia32_unistd.h>
28#include <asm/user32.h>
29#include <uapi/asm/sigcontext.h>
30#include <asm/proto.h>
31#include <asm/vdso.h>
32#include <asm/sigframe.h>
33#include <asm/sighandling.h>
34#include <asm/sys_ia32.h>
35#include <asm/smap.h>
36
37/*
38 * Do a signal return; undo the signal stack.
39 */
40#define loadsegment_gs(v) load_gs_index(v)
41#define loadsegment_fs(v) loadsegment(fs, v)
42#define loadsegment_ds(v) loadsegment(ds, v)
43#define loadsegment_es(v) loadsegment(es, v)
44
45#define get_user_seg(seg) ({ unsigned int v; savesegment(seg, v); v; })
46#define set_user_seg(seg, v) loadsegment_##seg(v)
47
48#define COPY(x) { \
49 get_user_ex(regs->x, &sc->x); \
50}
51
52#define GET_SEG(seg) ({ \
53 unsigned short tmp; \
54 get_user_ex(tmp, &sc->seg); \
55 tmp; \
56})
57
58#define COPY_SEG_CPL3(seg) do { \
59 regs->seg = GET_SEG(seg) | 3; \
60} while (0)
61
62#define RELOAD_SEG(seg) { \
63 unsigned int pre = GET_SEG(seg); \
64 unsigned int cur = get_user_seg(seg); \
65 pre |= 3; \
66 if (pre != cur) \
67 set_user_seg(seg, pre); \
68}
69
70static int ia32_restore_sigcontext(struct pt_regs *regs,
71 struct sigcontext_32 __user *sc)
72{
73 unsigned int tmpflags, err = 0;
74 void __user *buf;
75 u32 tmp;
76
77 /* Always make any pending restarted system calls return -EINTR */
78 current->restart_block.fn = do_no_restart_syscall;
79
80 get_user_try {
81 /*
82 * Reload fs and gs if they have changed in the signal
83 * handler. This does not handle long fs/gs base changes in
84 * the handler, but does not clobber them at least in the
85 * normal case.
86 */
87 RELOAD_SEG(gs);
88 RELOAD_SEG(fs);
89 RELOAD_SEG(ds);
90 RELOAD_SEG(es);
91
92 COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx);
93 COPY(dx); COPY(cx); COPY(ip); COPY(ax);
94 /* Don't touch extended registers */
95
96 COPY_SEG_CPL3(cs);
97 COPY_SEG_CPL3(ss);
98
99 get_user_ex(tmpflags, &sc->flags);
100 regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
101 /* disable syscall checks */
102 regs->orig_ax = -1;
103
104 get_user_ex(tmp, &sc->fpstate);
105 buf = compat_ptr(tmp);
106 } get_user_catch(err);
107
108 err |= fpu__restore_sig(buf, 1);
109
110 force_iret();
111
112 return err;
113}
114
115asmlinkage long sys32_sigreturn(void)
116{
117 struct pt_regs *regs = current_pt_regs();
118 struct sigframe_ia32 __user *frame = (struct sigframe_ia32 __user *)(regs->sp-8);
119 sigset_t set;
120
121 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
122 goto badframe;
123 if (__get_user(set.sig[0], &frame->sc.oldmask)
124 || (_COMPAT_NSIG_WORDS > 1
125 && __copy_from_user((((char *) &set.sig) + 4),
126 &frame->extramask,
127 sizeof(frame->extramask))))
128 goto badframe;
129
130 set_current_blocked(&set);
131
132 if (ia32_restore_sigcontext(regs, &frame->sc))
133 goto badframe;
134 return regs->ax;
135
136badframe:
137 signal_fault(regs, frame, "32bit sigreturn");
138 return 0;
139}
140
141asmlinkage long sys32_rt_sigreturn(void)
142{
143 struct pt_regs *regs = current_pt_regs();
144 struct rt_sigframe_ia32 __user *frame;
145 sigset_t set;
146
147 frame = (struct rt_sigframe_ia32 __user *)(regs->sp - 4);
148
149 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
150 goto badframe;
151 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
152 goto badframe;
153
154 set_current_blocked(&set);
155
156 if (ia32_restore_sigcontext(regs, &frame->uc.uc_mcontext))
157 goto badframe;
158
159 if (compat_restore_altstack(&frame->uc.uc_stack))
160 goto badframe;
161
162 return regs->ax;
163
164badframe:
165 signal_fault(regs, frame, "32bit rt sigreturn");
166 return 0;
167}
168
169/*
170 * Set up a signal frame.
171 */
172
173static int ia32_setup_sigcontext(struct sigcontext_32 __user *sc,
174 void __user *fpstate,
175 struct pt_regs *regs, unsigned int mask)
176{
177 int err = 0;
178
179 put_user_try {
180 put_user_ex(get_user_seg(gs), (unsigned int __user *)&sc->gs);
181 put_user_ex(get_user_seg(fs), (unsigned int __user *)&sc->fs);
182 put_user_ex(get_user_seg(ds), (unsigned int __user *)&sc->ds);
183 put_user_ex(get_user_seg(es), (unsigned int __user *)&sc->es);
184
185 put_user_ex(regs->di, &sc->di);
186 put_user_ex(regs->si, &sc->si);
187 put_user_ex(regs->bp, &sc->bp);
188 put_user_ex(regs->sp, &sc->sp);
189 put_user_ex(regs->bx, &sc->bx);
190 put_user_ex(regs->dx, &sc->dx);
191 put_user_ex(regs->cx, &sc->cx);
192 put_user_ex(regs->ax, &sc->ax);
193 put_user_ex(current->thread.trap_nr, &sc->trapno);
194 put_user_ex(current->thread.error_code, &sc->err);
195 put_user_ex(regs->ip, &sc->ip);
196 put_user_ex(regs->cs, (unsigned int __user *)&sc->cs);
197 put_user_ex(regs->flags, &sc->flags);
198 put_user_ex(regs->sp, &sc->sp_at_signal);
199 put_user_ex(regs->ss, (unsigned int __user *)&sc->ss);
200
201 put_user_ex(ptr_to_compat(fpstate), &sc->fpstate);
202
203 /* non-iBCS2 extensions.. */
204 put_user_ex(mask, &sc->oldmask);
205 put_user_ex(current->thread.cr2, &sc->cr2);
206 } put_user_catch(err);
207
208 return err;
209}
210
211/*
212 * Determine which stack to use..
213 */
214static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs,
215 size_t frame_size,
216 void __user **fpstate)
217{
218 struct fpu *fpu = ¤t->thread.fpu;
219 unsigned long sp;
220
221 /* Default to using normal stack */
222 sp = regs->sp;
223
224 /* This is the X/Open sanctioned signal stack switching. */
225 if (ksig->ka.sa.sa_flags & SA_ONSTACK)
226 sp = sigsp(sp, ksig);
227 /* This is the legacy signal stack switching. */
228 else if ((regs->ss & 0xffff) != __USER32_DS &&
229 !(ksig->ka.sa.sa_flags & SA_RESTORER) &&
230 ksig->ka.sa.sa_restorer)
231 sp = (unsigned long) ksig->ka.sa.sa_restorer;
232
233 if (fpu->fpstate_active) {
234 unsigned long fx_aligned, math_size;
235
236 sp = fpu__alloc_mathframe(sp, 1, &fx_aligned, &math_size);
237 *fpstate = (struct _fpstate_32 __user *) sp;
238 if (copy_fpstate_to_sigframe(*fpstate, (void __user *)fx_aligned,
239 math_size) < 0)
240 return (void __user *) -1L;
241 }
242
243 sp -= frame_size;
244 /* Align the stack pointer according to the i386 ABI,
245 * i.e. so that on function entry ((sp + 4) & 15) == 0. */
246 sp = ((sp + 4) & -16ul) - 4;
247 return (void __user *) sp;
248}
249
250int ia32_setup_frame(int sig, struct ksignal *ksig,
251 compat_sigset_t *set, struct pt_regs *regs)
252{
253 struct sigframe_ia32 __user *frame;
254 void __user *restorer;
255 int err = 0;
256 void __user *fpstate = NULL;
257
258 /* copy_to_user optimizes that into a single 8 byte store */
259 static const struct {
260 u16 poplmovl;
261 u32 val;
262 u16 int80;
263 } __attribute__((packed)) code = {
264 0xb858, /* popl %eax ; movl $...,%eax */
265 __NR_ia32_sigreturn,
266 0x80cd, /* int $0x80 */
267 };
268
269 frame = get_sigframe(ksig, regs, sizeof(*frame), &fpstate);
270
271 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
272 return -EFAULT;
273
274 if (__put_user(sig, &frame->sig))
275 return -EFAULT;
276
277 if (ia32_setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0]))
278 return -EFAULT;
279
280 if (_COMPAT_NSIG_WORDS > 1) {
281 if (__copy_to_user(frame->extramask, &set->sig[1],
282 sizeof(frame->extramask)))
283 return -EFAULT;
284 }
285
286 if (ksig->ka.sa.sa_flags & SA_RESTORER) {
287 restorer = ksig->ka.sa.sa_restorer;
288 } else {
289 /* Return stub is in 32bit vsyscall page */
290 if (current->mm->context.vdso)
291 restorer = current->mm->context.vdso +
292 vdso_image_32.sym___kernel_sigreturn;
293 else
294 restorer = &frame->retcode;
295 }
296
297 put_user_try {
298 put_user_ex(ptr_to_compat(restorer), &frame->pretcode);
299
300 /*
301 * These are actually not used anymore, but left because some
302 * gdb versions depend on them as a marker.
303 */
304 put_user_ex(*((u64 *)&code), (u64 __user *)frame->retcode);
305 } put_user_catch(err);
306
307 if (err)
308 return -EFAULT;
309
310 /* Set up registers for signal handler */
311 regs->sp = (unsigned long) frame;
312 regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
313
314 /* Make -mregparm=3 work */
315 regs->ax = sig;
316 regs->dx = 0;
317 regs->cx = 0;
318
319 loadsegment(ds, __USER32_DS);
320 loadsegment(es, __USER32_DS);
321
322 regs->cs = __USER32_CS;
323 regs->ss = __USER32_DS;
324
325 return 0;
326}
327
328int ia32_setup_rt_frame(int sig, struct ksignal *ksig,
329 compat_sigset_t *set, struct pt_regs *regs)
330{
331 struct rt_sigframe_ia32 __user *frame;
332 void __user *restorer;
333 int err = 0;
334 void __user *fpstate = NULL;
335
336 /* __copy_to_user optimizes that into a single 8 byte store */
337 static const struct {
338 u8 movl;
339 u32 val;
340 u16 int80;
341 u8 pad;
342 } __attribute__((packed)) code = {
343 0xb8,
344 __NR_ia32_rt_sigreturn,
345 0x80cd,
346 0,
347 };
348
349 frame = get_sigframe(ksig, regs, sizeof(*frame), &fpstate);
350
351 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
352 return -EFAULT;
353
354 put_user_try {
355 put_user_ex(sig, &frame->sig);
356 put_user_ex(ptr_to_compat(&frame->info), &frame->pinfo);
357 put_user_ex(ptr_to_compat(&frame->uc), &frame->puc);
358
359 /* Create the ucontext. */
360 if (cpu_has_xsave)
361 put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags);
362 else
363 put_user_ex(0, &frame->uc.uc_flags);
364 put_user_ex(0, &frame->uc.uc_link);
365 compat_save_altstack_ex(&frame->uc.uc_stack, regs->sp);
366
367 if (ksig->ka.sa.sa_flags & SA_RESTORER)
368 restorer = ksig->ka.sa.sa_restorer;
369 else
370 restorer = current->mm->context.vdso +
371 vdso_image_32.sym___kernel_rt_sigreturn;
372 put_user_ex(ptr_to_compat(restorer), &frame->pretcode);
373
374 /*
375 * Not actually used anymore, but left because some gdb
376 * versions need it.
377 */
378 put_user_ex(*((u64 *)&code), (u64 __user *)frame->retcode);
379 } put_user_catch(err);
380
381 err |= copy_siginfo_to_user32(&frame->info, &ksig->info);
382 err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
383 regs, set->sig[0]);
384 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
385
386 if (err)
387 return -EFAULT;
388
389 /* Set up registers for signal handler */
390 regs->sp = (unsigned long) frame;
391 regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
392
393 /* Make -mregparm=3 work */
394 regs->ax = sig;
395 regs->dx = (unsigned long) &frame->info;
396 regs->cx = (unsigned long) &frame->uc;
397
398 loadsegment(ds, __USER32_DS);
399 loadsegment(es, __USER32_DS);
400
401 regs->cs = __USER32_CS;
402 regs->ss = __USER32_DS;
403
404 return 0;
405}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/arch/x86_64/ia32/ia32_signal.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 *
7 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
8 * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes
9 * 2000-12-* x86-64 compatibility mode signal handling by Andi Kleen
10 */
11
12#include <linux/sched.h>
13#include <linux/sched/task_stack.h>
14#include <linux/mm.h>
15#include <linux/smp.h>
16#include <linux/kernel.h>
17#include <linux/errno.h>
18#include <linux/wait.h>
19#include <linux/unistd.h>
20#include <linux/stddef.h>
21#include <linux/personality.h>
22#include <linux/compat.h>
23#include <linux/binfmts.h>
24#include <linux/syscalls.h>
25#include <asm/ucontext.h>
26#include <linux/uaccess.h>
27#include <asm/fpu/internal.h>
28#include <asm/fpu/signal.h>
29#include <asm/ptrace.h>
30#include <asm/ia32_unistd.h>
31#include <asm/user32.h>
32#include <uapi/asm/sigcontext.h>
33#include <asm/proto.h>
34#include <asm/vdso.h>
35#include <asm/sigframe.h>
36#include <asm/sighandling.h>
37#include <asm/smap.h>
38
39static inline void reload_segments(struct sigcontext_32 *sc)
40{
41 unsigned int cur;
42
43 savesegment(gs, cur);
44 if ((sc->gs | 0x03) != cur)
45 load_gs_index(sc->gs | 0x03);
46 savesegment(fs, cur);
47 if ((sc->fs | 0x03) != cur)
48 loadsegment(fs, sc->fs | 0x03);
49 savesegment(ds, cur);
50 if ((sc->ds | 0x03) != cur)
51 loadsegment(ds, sc->ds | 0x03);
52 savesegment(es, cur);
53 if ((sc->es | 0x03) != cur)
54 loadsegment(es, sc->es | 0x03);
55}
56
57/*
58 * Do a signal return; undo the signal stack.
59 */
60static int ia32_restore_sigcontext(struct pt_regs *regs,
61 struct sigcontext_32 __user *usc)
62{
63 struct sigcontext_32 sc;
64
65 /* Always make any pending restarted system calls return -EINTR */
66 current->restart_block.fn = do_no_restart_syscall;
67
68 if (unlikely(copy_from_user(&sc, usc, sizeof(sc))))
69 return -EFAULT;
70
71 /* Get only the ia32 registers. */
72 regs->bx = sc.bx;
73 regs->cx = sc.cx;
74 regs->dx = sc.dx;
75 regs->si = sc.si;
76 regs->di = sc.di;
77 regs->bp = sc.bp;
78 regs->ax = sc.ax;
79 regs->sp = sc.sp;
80 regs->ip = sc.ip;
81
82 /* Get CS/SS and force CPL3 */
83 regs->cs = sc.cs | 0x03;
84 regs->ss = sc.ss | 0x03;
85
86 regs->flags = (regs->flags & ~FIX_EFLAGS) | (sc.flags & FIX_EFLAGS);
87 /* disable syscall checks */
88 regs->orig_ax = -1;
89
90 /*
91 * Reload fs and gs if they have changed in the signal
92 * handler. This does not handle long fs/gs base changes in
93 * the handler, but does not clobber them at least in the
94 * normal case.
95 */
96 reload_segments(&sc);
97 return fpu__restore_sig(compat_ptr(sc.fpstate), 1);
98}
99
100COMPAT_SYSCALL_DEFINE0(sigreturn)
101{
102 struct pt_regs *regs = current_pt_regs();
103 struct sigframe_ia32 __user *frame = (struct sigframe_ia32 __user *)(regs->sp-8);
104 sigset_t set;
105
106 if (!access_ok(frame, sizeof(*frame)))
107 goto badframe;
108 if (__get_user(set.sig[0], &frame->sc.oldmask)
109 || __get_user(((__u32 *)&set)[1], &frame->extramask[0]))
110 goto badframe;
111
112 set_current_blocked(&set);
113
114 if (ia32_restore_sigcontext(regs, &frame->sc))
115 goto badframe;
116 return regs->ax;
117
118badframe:
119 signal_fault(regs, frame, "32bit sigreturn");
120 return 0;
121}
122
123COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
124{
125 struct pt_regs *regs = current_pt_regs();
126 struct rt_sigframe_ia32 __user *frame;
127 sigset_t set;
128
129 frame = (struct rt_sigframe_ia32 __user *)(regs->sp - 4);
130
131 if (!access_ok(frame, sizeof(*frame)))
132 goto badframe;
133 if (__get_user(set.sig[0], (__u64 __user *)&frame->uc.uc_sigmask))
134 goto badframe;
135
136 set_current_blocked(&set);
137
138 if (ia32_restore_sigcontext(regs, &frame->uc.uc_mcontext))
139 goto badframe;
140
141 if (compat_restore_altstack(&frame->uc.uc_stack))
142 goto badframe;
143
144 return regs->ax;
145
146badframe:
147 signal_fault(regs, frame, "32bit rt sigreturn");
148 return 0;
149}
150
151/*
152 * Set up a signal frame.
153 */
154
155#define get_user_seg(seg) ({ unsigned int v; savesegment(seg, v); v; })
156
157static __always_inline int
158__unsafe_setup_sigcontext32(struct sigcontext_32 __user *sc,
159 void __user *fpstate,
160 struct pt_regs *regs, unsigned int mask)
161{
162 unsafe_put_user(get_user_seg(gs), (unsigned int __user *)&sc->gs, Efault);
163 unsafe_put_user(get_user_seg(fs), (unsigned int __user *)&sc->fs, Efault);
164 unsafe_put_user(get_user_seg(ds), (unsigned int __user *)&sc->ds, Efault);
165 unsafe_put_user(get_user_seg(es), (unsigned int __user *)&sc->es, Efault);
166
167 unsafe_put_user(regs->di, &sc->di, Efault);
168 unsafe_put_user(regs->si, &sc->si, Efault);
169 unsafe_put_user(regs->bp, &sc->bp, Efault);
170 unsafe_put_user(regs->sp, &sc->sp, Efault);
171 unsafe_put_user(regs->bx, &sc->bx, Efault);
172 unsafe_put_user(regs->dx, &sc->dx, Efault);
173 unsafe_put_user(regs->cx, &sc->cx, Efault);
174 unsafe_put_user(regs->ax, &sc->ax, Efault);
175 unsafe_put_user(current->thread.trap_nr, &sc->trapno, Efault);
176 unsafe_put_user(current->thread.error_code, &sc->err, Efault);
177 unsafe_put_user(regs->ip, &sc->ip, Efault);
178 unsafe_put_user(regs->cs, (unsigned int __user *)&sc->cs, Efault);
179 unsafe_put_user(regs->flags, &sc->flags, Efault);
180 unsafe_put_user(regs->sp, &sc->sp_at_signal, Efault);
181 unsafe_put_user(regs->ss, (unsigned int __user *)&sc->ss, Efault);
182
183 unsafe_put_user(ptr_to_compat(fpstate), &sc->fpstate, Efault);
184
185 /* non-iBCS2 extensions.. */
186 unsafe_put_user(mask, &sc->oldmask, Efault);
187 unsafe_put_user(current->thread.cr2, &sc->cr2, Efault);
188 return 0;
189
190Efault:
191 return -EFAULT;
192}
193
194#define unsafe_put_sigcontext32(sc, fp, regs, set, label) \
195do { \
196 if (__unsafe_setup_sigcontext32(sc, fp, regs, set->sig[0])) \
197 goto label; \
198} while(0)
199
200/*
201 * Determine which stack to use..
202 */
203static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs,
204 size_t frame_size,
205 void __user **fpstate)
206{
207 unsigned long sp, fx_aligned, math_size;
208
209 /* Default to using normal stack */
210 sp = regs->sp;
211
212 /* This is the X/Open sanctioned signal stack switching. */
213 if (ksig->ka.sa.sa_flags & SA_ONSTACK)
214 sp = sigsp(sp, ksig);
215 /* This is the legacy signal stack switching. */
216 else if (regs->ss != __USER32_DS &&
217 !(ksig->ka.sa.sa_flags & SA_RESTORER) &&
218 ksig->ka.sa.sa_restorer)
219 sp = (unsigned long) ksig->ka.sa.sa_restorer;
220
221 sp = fpu__alloc_mathframe(sp, 1, &fx_aligned, &math_size);
222 *fpstate = (struct _fpstate_32 __user *) sp;
223 if (copy_fpstate_to_sigframe(*fpstate, (void __user *)fx_aligned,
224 math_size) < 0)
225 return (void __user *) -1L;
226
227 sp -= frame_size;
228 /* Align the stack pointer according to the i386 ABI,
229 * i.e. so that on function entry ((sp + 4) & 15) == 0. */
230 sp = ((sp + 4) & -16ul) - 4;
231 return (void __user *) sp;
232}
233
234int ia32_setup_frame(int sig, struct ksignal *ksig,
235 compat_sigset_t *set, struct pt_regs *regs)
236{
237 struct sigframe_ia32 __user *frame;
238 void __user *restorer;
239 void __user *fp = NULL;
240
241 /* copy_to_user optimizes that into a single 8 byte store */
242 static const struct {
243 u16 poplmovl;
244 u32 val;
245 u16 int80;
246 } __attribute__((packed)) code = {
247 0xb858, /* popl %eax ; movl $...,%eax */
248 __NR_ia32_sigreturn,
249 0x80cd, /* int $0x80 */
250 };
251
252 frame = get_sigframe(ksig, regs, sizeof(*frame), &fp);
253
254 if (ksig->ka.sa.sa_flags & SA_RESTORER) {
255 restorer = ksig->ka.sa.sa_restorer;
256 } else {
257 /* Return stub is in 32bit vsyscall page */
258 if (current->mm->context.vdso)
259 restorer = current->mm->context.vdso +
260 vdso_image_32.sym___kernel_sigreturn;
261 else
262 restorer = &frame->retcode;
263 }
264
265 if (!user_access_begin(frame, sizeof(*frame)))
266 return -EFAULT;
267
268 unsafe_put_user(sig, &frame->sig, Efault);
269 unsafe_put_sigcontext32(&frame->sc, fp, regs, set, Efault);
270 unsafe_put_user(set->sig[1], &frame->extramask[0], Efault);
271 unsafe_put_user(ptr_to_compat(restorer), &frame->pretcode, Efault);
272 /*
273 * These are actually not used anymore, but left because some
274 * gdb versions depend on them as a marker.
275 */
276 unsafe_put_user(*((u64 *)&code), (u64 __user *)frame->retcode, Efault);
277 user_access_end();
278
279 /* Set up registers for signal handler */
280 regs->sp = (unsigned long) frame;
281 regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
282
283 /* Make -mregparm=3 work */
284 regs->ax = sig;
285 regs->dx = 0;
286 regs->cx = 0;
287
288 loadsegment(ds, __USER32_DS);
289 loadsegment(es, __USER32_DS);
290
291 regs->cs = __USER32_CS;
292 regs->ss = __USER32_DS;
293
294 return 0;
295Efault:
296 user_access_end();
297 return -EFAULT;
298}
299
300int ia32_setup_rt_frame(int sig, struct ksignal *ksig,
301 compat_sigset_t *set, struct pt_regs *regs)
302{
303 struct rt_sigframe_ia32 __user *frame;
304 void __user *restorer;
305 void __user *fp = NULL;
306
307 /* unsafe_put_user optimizes that into a single 8 byte store */
308 static const struct {
309 u8 movl;
310 u32 val;
311 u16 int80;
312 u8 pad;
313 } __attribute__((packed)) code = {
314 0xb8,
315 __NR_ia32_rt_sigreturn,
316 0x80cd,
317 0,
318 };
319
320 frame = get_sigframe(ksig, regs, sizeof(*frame), &fp);
321
322 if (!user_access_begin(frame, sizeof(*frame)))
323 return -EFAULT;
324
325 unsafe_put_user(sig, &frame->sig, Efault);
326 unsafe_put_user(ptr_to_compat(&frame->info), &frame->pinfo, Efault);
327 unsafe_put_user(ptr_to_compat(&frame->uc), &frame->puc, Efault);
328
329 /* Create the ucontext. */
330 if (static_cpu_has(X86_FEATURE_XSAVE))
331 unsafe_put_user(UC_FP_XSTATE, &frame->uc.uc_flags, Efault);
332 else
333 unsafe_put_user(0, &frame->uc.uc_flags, Efault);
334 unsafe_put_user(0, &frame->uc.uc_link, Efault);
335 unsafe_compat_save_altstack(&frame->uc.uc_stack, regs->sp, Efault);
336
337 if (ksig->ka.sa.sa_flags & SA_RESTORER)
338 restorer = ksig->ka.sa.sa_restorer;
339 else
340 restorer = current->mm->context.vdso +
341 vdso_image_32.sym___kernel_rt_sigreturn;
342 unsafe_put_user(ptr_to_compat(restorer), &frame->pretcode, Efault);
343
344 /*
345 * Not actually used anymore, but left because some gdb
346 * versions need it.
347 */
348 unsafe_put_user(*((u64 *)&code), (u64 __user *)frame->retcode, Efault);
349 unsafe_put_sigcontext32(&frame->uc.uc_mcontext, fp, regs, set, Efault);
350 unsafe_put_user(*(__u64 *)set, (__u64 *)&frame->uc.uc_sigmask, Efault);
351 user_access_end();
352
353 if (__copy_siginfo_to_user32(&frame->info, &ksig->info))
354 return -EFAULT;
355
356 /* Set up registers for signal handler */
357 regs->sp = (unsigned long) frame;
358 regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
359
360 /* Make -mregparm=3 work */
361 regs->ax = sig;
362 regs->dx = (unsigned long) &frame->info;
363 regs->cx = (unsigned long) &frame->uc;
364
365 loadsegment(ds, __USER32_DS);
366 loadsegment(es, __USER32_DS);
367
368 regs->cs = __USER32_CS;
369 regs->ss = __USER32_DS;
370
371 return 0;
372Efault:
373 user_access_end();
374 return -EFAULT;
375}