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-rw-r--r--arch/um/sys-x86_64/signal.c290
1 files changed, 290 insertions, 0 deletions
diff --git a/arch/um/sys-x86_64/signal.c b/arch/um/sys-x86_64/signal.c
new file mode 100644
index 00000000000..b6b65c7c7a7
--- /dev/null
+++ b/arch/um/sys-x86_64/signal.c
@@ -0,0 +1,290 @@
1/*
2 * Copyright (C) 2003 PathScale, Inc.
3 * Copyright (C) 2003 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 * Licensed under the GPL
5 */
6
7#include <linux/personality.h>
8#include <linux/ptrace.h>
9#include <linux/kernel.h>
10#include <asm/unistd.h>
11#include <asm/uaccess.h>
12#include <asm/ucontext.h>
13#include "frame_kern.h"
14#include "skas.h"
15
16void copy_sc(struct uml_pt_regs *regs, void *from)
17{
18 struct sigcontext *sc = from;
19
20#define GETREG(regs, regno, sc, regname) \
21 (regs)->gp[(regno) / sizeof(unsigned long)] = (sc)->regname
22
23 GETREG(regs, R8, sc, r8);
24 GETREG(regs, R9, sc, r9);
25 GETREG(regs, R10, sc, r10);
26 GETREG(regs, R11, sc, r11);
27 GETREG(regs, R12, sc, r12);
28 GETREG(regs, R13, sc, r13);
29 GETREG(regs, R14, sc, r14);
30 GETREG(regs, R15, sc, r15);
31 GETREG(regs, RDI, sc, di);
32 GETREG(regs, RSI, sc, si);
33 GETREG(regs, RBP, sc, bp);
34 GETREG(regs, RBX, sc, bx);
35 GETREG(regs, RDX, sc, dx);
36 GETREG(regs, RAX, sc, ax);
37 GETREG(regs, RCX, sc, cx);
38 GETREG(regs, RSP, sc, sp);
39 GETREG(regs, RIP, sc, ip);
40 GETREG(regs, EFLAGS, sc, flags);
41 GETREG(regs, CS, sc, cs);
42
43#undef GETREG
44}
45
46static int copy_sc_from_user(struct pt_regs *regs,
47 struct sigcontext __user *from,
48 struct _fpstate __user *fpp)
49{
50 struct user_i387_struct fp;
51 int err = 0;
52
53#define GETREG(regs, regno, sc, regname) \
54 __get_user((regs)->regs.gp[(regno) / sizeof(unsigned long)], \
55 &(sc)->regname)
56
57 err |= GETREG(regs, R8, from, r8);
58 err |= GETREG(regs, R9, from, r9);
59 err |= GETREG(regs, R10, from, r10);
60 err |= GETREG(regs, R11, from, r11);
61 err |= GETREG(regs, R12, from, r12);
62 err |= GETREG(regs, R13, from, r13);
63 err |= GETREG(regs, R14, from, r14);
64 err |= GETREG(regs, R15, from, r15);
65 err |= GETREG(regs, RDI, from, di);
66 err |= GETREG(regs, RSI, from, si);
67 err |= GETREG(regs, RBP, from, bp);
68 err |= GETREG(regs, RBX, from, bx);
69 err |= GETREG(regs, RDX, from, dx);
70 err |= GETREG(regs, RAX, from, ax);
71 err |= GETREG(regs, RCX, from, cx);
72 err |= GETREG(regs, RSP, from, sp);
73 err |= GETREG(regs, RIP, from, ip);
74 err |= GETREG(regs, EFLAGS, from, flags);
75 err |= GETREG(regs, CS, from, cs);
76 if (err)
77 return 1;
78
79#undef GETREG
80
81 err = copy_from_user(&fp, fpp, sizeof(struct user_i387_struct));
82 if (err)
83 return 1;
84
85 err = restore_fp_registers(userspace_pid[current_thread_info()->cpu],
86 (unsigned long *) &fp);
87 if (err < 0) {
88 printk(KERN_ERR "copy_sc_from_user - "
89 "restore_fp_registers failed, errno = %d\n",
90 -err);
91 return 1;
92 }
93
94 return 0;
95}
96
97static int copy_sc_to_user(struct sigcontext __user *to,
98 struct _fpstate __user *to_fp, struct pt_regs *regs,
99 unsigned long mask, unsigned long sp)
100{
101 struct faultinfo * fi = &current->thread.arch.faultinfo;
102 struct user_i387_struct fp;
103 int err = 0;
104
105 err |= __put_user(0, &to->gs);
106 err |= __put_user(0, &to->fs);
107
108#define PUTREG(regs, regno, sc, regname) \
109 __put_user((regs)->regs.gp[(regno) / sizeof(unsigned long)], \
110 &(sc)->regname)
111
112 err |= PUTREG(regs, RDI, to, di);
113 err |= PUTREG(regs, RSI, to, si);
114 err |= PUTREG(regs, RBP, to, bp);
115 /*
116 * Must use original RSP, which is passed in, rather than what's in
117 * the pt_regs, because that's already been updated to point at the
118 * signal frame.
119 */
120 err |= __put_user(sp, &to->sp);
121 err |= PUTREG(regs, RBX, to, bx);
122 err |= PUTREG(regs, RDX, to, dx);
123 err |= PUTREG(regs, RCX, to, cx);
124 err |= PUTREG(regs, RAX, to, ax);
125 err |= PUTREG(regs, R8, to, r8);
126 err |= PUTREG(regs, R9, to, r9);
127 err |= PUTREG(regs, R10, to, r10);
128 err |= PUTREG(regs, R11, to, r11);
129 err |= PUTREG(regs, R12, to, r12);
130 err |= PUTREG(regs, R13, to, r13);
131 err |= PUTREG(regs, R14, to, r14);
132 err |= PUTREG(regs, R15, to, r15);
133 err |= PUTREG(regs, CS, to, cs); /* XXX x86_64 doesn't do this */
134
135 err |= __put_user(fi->cr2, &to->cr2);
136 err |= __put_user(fi->error_code, &to->err);
137 err |= __put_user(fi->trap_no, &to->trapno);
138
139 err |= PUTREG(regs, RIP, to, ip);
140 err |= PUTREG(regs, EFLAGS, to, flags);
141#undef PUTREG
142
143 err |= __put_user(mask, &to->oldmask);
144 if (err)
145 return 1;
146
147 err = save_fp_registers(userspace_pid[current_thread_info()->cpu],
148 (unsigned long *) &fp);
149 if (err < 0) {
150 printk(KERN_ERR "copy_sc_from_user - restore_fp_registers "
151 "failed, errno = %d\n", -err);
152 return 1;
153 }
154
155 if (copy_to_user(to_fp, &fp, sizeof(struct user_i387_struct)))
156 return 1;
157
158 return err;
159}
160
161struct rt_sigframe
162{
163 char __user *pretcode;
164 struct ucontext uc;
165 struct siginfo info;
166 struct _fpstate fpstate;
167};
168
169int setup_signal_stack_si(unsigned long stack_top, int sig,
170 struct k_sigaction *ka, struct pt_regs * regs,
171 siginfo_t *info, sigset_t *set)
172{
173 struct rt_sigframe __user *frame;
174 unsigned long save_sp = PT_REGS_RSP(regs);
175 int err = 0;
176 struct task_struct *me = current;
177
178 frame = (struct rt_sigframe __user *)
179 round_down(stack_top - sizeof(struct rt_sigframe), 16);
180 /* Subtract 128 for a red zone and 8 for proper alignment */
181 frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);
182
183 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
184 goto out;
185
186 if (ka->sa.sa_flags & SA_SIGINFO) {
187 err |= copy_siginfo_to_user(&frame->info, info);
188 if (err)
189 goto out;
190 }
191
192 /*
193 * Update SP now because the page fault handler refuses to extend
194 * the stack if the faulting address is too far below the current
195 * SP, which frame now certainly is. If there's an error, the original
196 * value is restored on the way out.
197 * When writing the sigcontext to the stack, we have to write the
198 * original value, so that's passed to copy_sc_to_user, which does
199 * the right thing with it.
200 */
201 PT_REGS_RSP(regs) = (unsigned long) frame;
202
203 /* Create the ucontext. */
204 err |= __put_user(0, &frame->uc.uc_flags);
205 err |= __put_user(0, &frame->uc.uc_link);
206 err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
207 err |= __put_user(sas_ss_flags(save_sp),
208 &frame->uc.uc_stack.ss_flags);
209 err |= __put_user(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
210 err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
211 set->sig[0], save_sp);
212 err |= __put_user(&frame->fpstate, &frame->uc.uc_mcontext.fpstate);
213 if (sizeof(*set) == 16) {
214 __put_user(set->sig[0], &frame->uc.uc_sigmask.sig[0]);
215 __put_user(set->sig[1], &frame->uc.uc_sigmask.sig[1]);
216 }
217 else
218 err |= __copy_to_user(&frame->uc.uc_sigmask, set,
219 sizeof(*set));
220
221 /*
222 * Set up to return from userspace. If provided, use a stub
223 * already in userspace.
224 */
225 /* x86-64 should always use SA_RESTORER. */
226 if (ka->sa.sa_flags & SA_RESTORER)
227 err |= __put_user(ka->sa.sa_restorer, &frame->pretcode);
228 else
229 /* could use a vstub here */
230 goto restore_sp;
231
232 if (err)
233 goto restore_sp;
234
235 /* Set up registers for signal handler */
236 {
237 struct exec_domain *ed = current_thread_info()->exec_domain;
238 if (unlikely(ed && ed->signal_invmap && sig < 32))
239 sig = ed->signal_invmap[sig];
240 }
241
242 PT_REGS_RDI(regs) = sig;
243 /* In case the signal handler was declared without prototypes */
244 PT_REGS_RAX(regs) = 0;
245
246 /*
247 * This also works for non SA_SIGINFO handlers because they expect the
248 * next argument after the signal number on the stack.
249 */
250 PT_REGS_RSI(regs) = (unsigned long) &frame->info;
251 PT_REGS_RDX(regs) = (unsigned long) &frame->uc;
252 PT_REGS_RIP(regs) = (unsigned long) ka->sa.sa_handler;
253 out:
254 return err;
255
256restore_sp:
257 PT_REGS_RSP(regs) = save_sp;
258 return err;
259}
260
261long sys_rt_sigreturn(struct pt_regs *regs)
262{
263 unsigned long sp = PT_REGS_SP(&current->thread.regs);
264 struct rt_sigframe __user *frame =
265 (struct rt_sigframe __user *)(sp - 8);
266 struct ucontext __user *uc = &frame->uc;
267 sigset_t set;
268
269 if (copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
270 goto segfault;
271
272 sigdelsetmask(&set, ~_BLOCKABLE);
273
274 spin_lock_irq(&current->sighand->siglock);
275 current->blocked = set;
276 recalc_sigpending();
277 spin_unlock_irq(&current->sighand->siglock);
278
279 if (copy_sc_from_user(&current->thread.regs, &uc->uc_mcontext,
280 &frame->fpstate))
281 goto segfault;
282
283 /* Avoid ERESTART handling */
284 PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
285 return PT_REGS_SYSCALL_RET(&current->thread.regs);
286
287 segfault:
288 force_sig(SIGSEGV, current);
289 return 0;
290}
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