2 * Copyright 2010 Tilera Corporation. All Rights Reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation, version 2.
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11 * NON INFRINGEMENT. See the GNU General Public License for
15 #include <linux/sched.h>
17 #include <linux/smp.h>
18 #include <linux/kernel.h>
19 #include <linux/signal.h>
20 #include <linux/errno.h>
21 #include <linux/wait.h>
22 #include <linux/unistd.h>
23 #include <linux/stddef.h>
24 #include <linux/personality.h>
25 #include <linux/suspend.h>
26 #include <linux/ptrace.h>
27 #include <linux/elf.h>
28 #include <linux/compat.h>
29 #include <linux/syscalls.h>
30 #include <linux/uaccess.h>
31 #include <asm/processor.h>
32 #include <asm/ucontext.h>
33 #include <asm/sigframe.h>
34 #include <asm/syscalls.h>
36 #include <arch/interrupts.h>
38 struct compat_ucontext
{
39 compat_ulong_t uc_flags
;
40 compat_uptr_t uc_link
;
41 struct compat_sigaltstack uc_stack
;
42 struct sigcontext uc_mcontext
;
43 sigset_t uc_sigmask
; /* mask last for extensibility */
46 struct compat_rt_sigframe
{
47 unsigned char save_area
[C_ABI_SAVE_AREA_SIZE
]; /* caller save area */
48 struct compat_siginfo info
;
49 struct compat_ucontext uc
;
52 int copy_siginfo_to_user32(struct compat_siginfo __user
*to
, const siginfo_t
*from
)
56 if (!access_ok(VERIFY_WRITE
, to
, sizeof(struct compat_siginfo
)))
59 /* If you change siginfo_t structure, please make sure that
60 this code is fixed accordingly.
61 It should never copy any pad contained in the structure
62 to avoid security leaks, but must copy the generic
63 3 ints plus the relevant union member. */
64 err
= __put_user(from
->si_signo
, &to
->si_signo
);
65 err
|= __put_user(from
->si_errno
, &to
->si_errno
);
66 err
|= __put_user((short)from
->si_code
, &to
->si_code
);
68 if (from
->si_code
< 0) {
69 err
|= __put_user(from
->si_pid
, &to
->si_pid
);
70 err
|= __put_user(from
->si_uid
, &to
->si_uid
);
71 err
|= __put_user(from
->si_int
, &to
->si_int
);
74 * First 32bits of unions are always present:
75 * si_pid === si_band === si_tid === si_addr(LS half)
77 err
|= __put_user(from
->_sifields
._pad
[0],
78 &to
->_sifields
._pad
[0]);
79 switch (from
->si_code
>> 16) {
80 case __SI_FAULT
>> 16:
83 err
|= __put_user(from
->si_utime
, &to
->si_utime
);
84 err
|= __put_user(from
->si_stime
, &to
->si_stime
);
85 err
|= __put_user(from
->si_status
, &to
->si_status
);
89 err
|= __put_user(from
->si_uid
, &to
->si_uid
);
92 err
|= __put_user(from
->si_fd
, &to
->si_fd
);
94 case __SI_TIMER
>> 16:
95 err
|= __put_user(from
->si_overrun
, &to
->si_overrun
);
96 err
|= __put_user(from
->si_int
, &to
->si_int
);
98 /* This is not generated by the kernel as of now. */
100 case __SI_MESGQ
>> 16:
101 err
|= __put_user(from
->si_uid
, &to
->si_uid
);
102 err
|= __put_user(from
->si_int
, &to
->si_int
);
109 int copy_siginfo_from_user32(siginfo_t
*to
, struct compat_siginfo __user
*from
)
113 if (!access_ok(VERIFY_READ
, from
, sizeof(struct compat_siginfo
)))
116 memset(to
, 0, sizeof(*to
));
118 err
= __get_user(to
->si_signo
, &from
->si_signo
);
119 err
|= __get_user(to
->si_errno
, &from
->si_errno
);
120 err
|= __get_user(to
->si_code
, &from
->si_code
);
122 err
|= __get_user(to
->si_pid
, &from
->si_pid
);
123 err
|= __get_user(to
->si_uid
, &from
->si_uid
);
124 err
|= __get_user(to
->si_int
, &from
->si_int
);
129 /* The assembly shim for this function arranges to ignore the return value. */
130 long compat_sys_rt_sigreturn(void)
132 struct pt_regs
*regs
= current_pt_regs();
133 struct compat_rt_sigframe __user
*frame
=
134 (struct compat_rt_sigframe __user
*) compat_ptr(regs
->sp
);
137 if (!access_ok(VERIFY_READ
, frame
, sizeof(*frame
)))
139 if (__copy_from_user(&set
, &frame
->uc
.uc_sigmask
, sizeof(set
)))
142 set_current_blocked(&set
);
144 if (restore_sigcontext(regs
, &frame
->uc
.uc_mcontext
))
147 if (compat_restore_altstack(&frame
->uc
.uc_stack
))
153 signal_fault("bad sigreturn frame", regs
, frame
, 0);
158 * Determine which stack to use..
160 static inline void __user
*compat_get_sigframe(struct k_sigaction
*ka
,
161 struct pt_regs
*regs
,
166 /* Default to using normal stack */
167 sp
= (unsigned long)compat_ptr(regs
->sp
);
170 * If we are on the alternate signal stack and would overflow
171 * it, don't. Return an always-bogus address instead so we
172 * will die with SIGSEGV.
174 if (on_sig_stack(sp
) && !likely(on_sig_stack(sp
- frame_size
)))
175 return (void __user __force
*)-1UL;
177 /* This is the X/Open sanctioned signal stack switching. */
178 if (ka
->sa
.sa_flags
& SA_ONSTACK
) {
179 if (sas_ss_flags(sp
) == 0)
180 sp
= current
->sas_ss_sp
+ current
->sas_ss_size
;
185 * Align the stack pointer according to the TILE ABI,
186 * i.e. so that on function entry (sp & 15) == 0.
189 return (void __user
*) sp
;
192 int compat_setup_rt_frame(struct ksignal
*ksig
, sigset_t
*set
,
193 struct pt_regs
*regs
)
195 unsigned long restorer
;
196 struct compat_rt_sigframe __user
*frame
;
197 int err
= 0, sig
= ksig
->sig
;
199 frame
= compat_get_sigframe(&ksig
->ka
, regs
, sizeof(*frame
));
201 if (!access_ok(VERIFY_WRITE
, frame
, sizeof(*frame
)))
204 /* Always write at least the signal number for the stack backtracer. */
205 if (ksig
->ka
.sa
.sa_flags
& SA_SIGINFO
) {
206 /* At sigreturn time, restore the callee-save registers too. */
207 err
|= copy_siginfo_to_user32(&frame
->info
, &ksig
->info
);
208 regs
->flags
|= PT_FLAGS_RESTORE_REGS
;
210 err
|= __put_user(ksig
->info
.si_signo
, &frame
->info
.si_signo
);
213 /* Create the ucontext. */
214 err
|= __clear_user(&frame
->save_area
, sizeof(frame
->save_area
));
215 err
|= __put_user(0, &frame
->uc
.uc_flags
);
216 err
|= __put_user(0, &frame
->uc
.uc_link
);
217 err
|= __compat_save_altstack(&frame
->uc
.uc_stack
, regs
->sp
);
218 err
|= setup_sigcontext(&frame
->uc
.uc_mcontext
, regs
);
219 err
|= __copy_to_user(&frame
->uc
.uc_sigmask
, set
, sizeof(*set
));
223 restorer
= VDSO_SYM(&__vdso_rt_sigreturn
);
224 if (ksig
->ka
.sa
.sa_flags
& SA_RESTORER
)
225 restorer
= ptr_to_compat_reg(ksig
->ka
.sa
.sa_restorer
);
228 * Set up registers for signal handler.
229 * Registers that we don't modify keep the value they had from
230 * user-space at the time we took the signal.
231 * We always pass siginfo and mcontext, regardless of SA_SIGINFO,
232 * since some things rely on this (e.g. glibc's debug/segfault.c).
234 regs
->pc
= ptr_to_compat_reg(ksig
->ka
.sa
.sa_handler
);
235 regs
->ex1
= PL_ICS_EX1(USER_PL
, 1); /* set crit sec in handler */
236 regs
->sp
= ptr_to_compat_reg(frame
);
238 regs
->regs
[0] = (unsigned long) sig
;
239 regs
->regs
[1] = ptr_to_compat_reg(&frame
->info
);
240 regs
->regs
[2] = ptr_to_compat_reg(&frame
->uc
);
241 regs
->flags
|= PT_FLAGS_CALLER_SAVES
;
245 trace_unhandled_signal("bad sigreturn frame", regs
,
246 (unsigned long)frame
, SIGSEGV
);