linux/arch/mips/kernel/signal32.c
Ralf Baechle 13fdd31abe [MIPS] Avoid double signal restarting.
In entry.S resume_userspace ... jal do_notify_resume form a loop through
which the kernel will iterate as long as work is pending.  If we
iterate through this loop more than once with no signal pending for at
least one but the last iteration we will take do the syscall restarting
multiple times resulting in a syscall return prior to the the syscall
instruction in userspace.  This may happen when debugging a multithreaded
program.

Debugging and original fix by Maciej; extended to other ABIs by me.

Signed-off-by: Maciej W. Rozycki <macro@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-09-27 13:37:33 +01:00

994 lines
26 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 1994 - 2000, 2006 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
*/
#include <linux/cache.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/syscalls.h>
#include <linux/errno.h>
#include <linux/wait.h>
#include <linux/ptrace.h>
#include <linux/compat.h>
#include <linux/suspend.h>
#include <linux/compiler.h>
#include <asm/abi.h>
#include <asm/asm.h>
#include <linux/bitops.h>
#include <asm/cacheflush.h>
#include <asm/sim.h>
#include <asm/uaccess.h>
#include <asm/ucontext.h>
#include <asm/system.h>
#include <asm/fpu.h>
#include <asm/war.h>
#define SI_PAD_SIZE32 ((SI_MAX_SIZE/sizeof(int)) - 3)
typedef struct compat_siginfo {
int si_signo;
int si_code;
int si_errno;
union {
int _pad[SI_PAD_SIZE32];
/* kill() */
struct {
compat_pid_t _pid; /* sender's pid */
compat_uid_t _uid; /* sender's uid */
} _kill;
/* SIGCHLD */
struct {
compat_pid_t _pid; /* which child */
compat_uid_t _uid; /* sender's uid */
int _status; /* exit code */
compat_clock_t _utime;
compat_clock_t _stime;
} _sigchld;
/* IRIX SIGCHLD */
struct {
compat_pid_t _pid; /* which child */
compat_clock_t _utime;
int _status; /* exit code */
compat_clock_t _stime;
} _irix_sigchld;
/* SIGILL, SIGFPE, SIGSEGV, SIGBUS */
struct {
s32 _addr; /* faulting insn/memory ref. */
} _sigfault;
/* SIGPOLL, SIGXFSZ (To do ...) */
struct {
int _band; /* POLL_IN, POLL_OUT, POLL_MSG */
int _fd;
} _sigpoll;
/* POSIX.1b timers */
struct {
timer_t _tid; /* timer id */
int _overrun; /* overrun count */
compat_sigval_t _sigval;/* same as below */
int _sys_private; /* not to be passed to user */
} _timer;
/* POSIX.1b signals */
struct {
compat_pid_t _pid; /* sender's pid */
compat_uid_t _uid; /* sender's uid */
compat_sigval_t _sigval;
} _rt;
} _sifields;
} compat_siginfo_t;
/*
* Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
*/
#define __NR_O32_sigreturn 4119
#define __NR_O32_rt_sigreturn 4193
#define __NR_O32_restart_syscall 4253
#define DEBUG_SIG 0
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
/* 32-bit compatibility types */
#define _NSIG_BPW32 32
#define _NSIG_WORDS32 (_NSIG / _NSIG_BPW32)
typedef struct {
unsigned int sig[_NSIG_WORDS32];
} sigset_t32;
typedef unsigned int __sighandler32_t;
typedef void (*vfptr_t)(void);
struct sigaction32 {
unsigned int sa_flags;
__sighandler32_t sa_handler;
compat_sigset_t sa_mask;
};
/* IRIX compatible stack_t */
typedef struct sigaltstack32 {
s32 ss_sp;
compat_size_t ss_size;
int ss_flags;
} stack32_t;
struct ucontext32 {
u32 uc_flags;
s32 uc_link;
stack32_t uc_stack;
struct sigcontext32 uc_mcontext;
sigset_t32 uc_sigmask; /* mask last for extensibility */
};
extern void __put_sigset_unknown_nsig(void);
extern void __get_sigset_unknown_nsig(void);
static inline int put_sigset(const sigset_t *kbuf, compat_sigset_t __user *ubuf)
{
int err = 0;
if (!access_ok(VERIFY_WRITE, ubuf, sizeof(*ubuf)))
return -EFAULT;
switch (_NSIG_WORDS) {
default:
__put_sigset_unknown_nsig();
case 2:
err |= __put_user (kbuf->sig[1] >> 32, &ubuf->sig[3]);
err |= __put_user (kbuf->sig[1] & 0xffffffff, &ubuf->sig[2]);
case 1:
err |= __put_user (kbuf->sig[0] >> 32, &ubuf->sig[1]);
err |= __put_user (kbuf->sig[0] & 0xffffffff, &ubuf->sig[0]);
}
return err;
}
static inline int get_sigset(sigset_t *kbuf, const compat_sigset_t __user *ubuf)
{
int err = 0;
unsigned long sig[4];
if (!access_ok(VERIFY_READ, ubuf, sizeof(*ubuf)))
return -EFAULT;
switch (_NSIG_WORDS) {
default:
__get_sigset_unknown_nsig();
case 2:
err |= __get_user (sig[3], &ubuf->sig[3]);
err |= __get_user (sig[2], &ubuf->sig[2]);
kbuf->sig[1] = sig[2] | (sig[3] << 32);
case 1:
err |= __get_user (sig[1], &ubuf->sig[1]);
err |= __get_user (sig[0], &ubuf->sig[0]);
kbuf->sig[0] = sig[0] | (sig[1] << 32);
}
return err;
}
/*
* Atomically swap in the new signal mask, and wait for a signal.
*/
save_static_function(sys32_sigsuspend);
__attribute_used__ noinline static int
_sys32_sigsuspend(nabi_no_regargs struct pt_regs regs)
{
compat_sigset_t __user *uset;
sigset_t newset;
uset = (compat_sigset_t __user *) regs.regs[4];
if (get_sigset(&newset, uset))
return -EFAULT;
sigdelsetmask(&newset, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
current->saved_sigmask = current->blocked;
current->blocked = newset;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
current->state = TASK_INTERRUPTIBLE;
schedule();
set_thread_flag(TIF_RESTORE_SIGMASK);
return -ERESTARTNOHAND;
}
save_static_function(sys32_rt_sigsuspend);
__attribute_used__ noinline static int
_sys32_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
{
compat_sigset_t __user *uset;
sigset_t newset;
size_t sigsetsize;
/* XXX Don't preclude handling different sized sigset_t's. */
sigsetsize = regs.regs[5];
if (sigsetsize != sizeof(compat_sigset_t))
return -EINVAL;
uset = (compat_sigset_t __user *) regs.regs[4];
if (get_sigset(&newset, uset))
return -EFAULT;
sigdelsetmask(&newset, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
current->saved_sigmask = current->blocked;
current->blocked = newset;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
current->state = TASK_INTERRUPTIBLE;
schedule();
set_thread_flag(TIF_RESTORE_SIGMASK);
return -ERESTARTNOHAND;
}
asmlinkage int sys32_sigaction(int sig, const struct sigaction32 __user *act,
struct sigaction32 __user *oact)
{
struct k_sigaction new_ka, old_ka;
int ret;
int err = 0;
if (act) {
old_sigset_t mask;
s32 handler;
if (!access_ok(VERIFY_READ, act, sizeof(*act)))
return -EFAULT;
err |= __get_user(handler, &act->sa_handler);
new_ka.sa.sa_handler = (void __user *)(s64)handler;
err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
err |= __get_user(mask, &act->sa_mask.sig[0]);
if (err)
return -EFAULT;
siginitset(&new_ka.sa.sa_mask, mask);
}
ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
if (!ret && oact) {
if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
return -EFAULT;
err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
err |= __put_user((u32)(u64)old_ka.sa.sa_handler,
&oact->sa_handler);
err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig);
err |= __put_user(0, &oact->sa_mask.sig[1]);
err |= __put_user(0, &oact->sa_mask.sig[2]);
err |= __put_user(0, &oact->sa_mask.sig[3]);
if (err)
return -EFAULT;
}
return ret;
}
asmlinkage int sys32_sigaltstack(nabi_no_regargs struct pt_regs regs)
{
const stack32_t __user *uss = (const stack32_t __user *) regs.regs[4];
stack32_t __user *uoss = (stack32_t __user *) regs.regs[5];
unsigned long usp = regs.regs[29];
stack_t kss, koss;
int ret, err = 0;
mm_segment_t old_fs = get_fs();
s32 sp;
if (uss) {
if (!access_ok(VERIFY_READ, uss, sizeof(*uss)))
return -EFAULT;
err |= __get_user(sp, &uss->ss_sp);
kss.ss_sp = (void __user *) (long) sp;
err |= __get_user(kss.ss_size, &uss->ss_size);
err |= __get_user(kss.ss_flags, &uss->ss_flags);
if (err)
return -EFAULT;
}
set_fs (KERNEL_DS);
ret = do_sigaltstack(uss ? (stack_t __user *)&kss : NULL,
uoss ? (stack_t __user *)&koss : NULL, usp);
set_fs (old_fs);
if (!ret && uoss) {
if (!access_ok(VERIFY_WRITE, uoss, sizeof(*uoss)))
return -EFAULT;
sp = (int) (unsigned long) koss.ss_sp;
err |= __put_user(sp, &uoss->ss_sp);
err |= __put_user(koss.ss_size, &uoss->ss_size);
err |= __put_user(koss.ss_flags, &uoss->ss_flags);
if (err)
return -EFAULT;
}
return ret;
}
static int restore_sigcontext32(struct pt_regs *regs, struct sigcontext32 __user *sc)
{
u32 used_math;
int err = 0;
s32 treg;
/* Always make any pending restarted system calls return -EINTR */
current_thread_info()->restart_block.fn = do_no_restart_syscall;
err |= __get_user(regs->cp0_epc, &sc->sc_pc);
err |= __get_user(regs->hi, &sc->sc_mdhi);
err |= __get_user(regs->lo, &sc->sc_mdlo);
if (cpu_has_dsp) {
err |= __get_user(treg, &sc->sc_hi1); mthi1(treg);
err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg);
err |= __get_user(treg, &sc->sc_hi2); mthi2(treg);
err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg);
err |= __get_user(treg, &sc->sc_hi3); mthi3(treg);
err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg);
err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK);
}
#define restore_gp_reg(i) do { \
err |= __get_user(regs->regs[i], &sc->sc_regs[i]); \
} while(0)
restore_gp_reg( 1); restore_gp_reg( 2); restore_gp_reg( 3);
restore_gp_reg( 4); restore_gp_reg( 5); restore_gp_reg( 6);
restore_gp_reg( 7); restore_gp_reg( 8); restore_gp_reg( 9);
restore_gp_reg(10); restore_gp_reg(11); restore_gp_reg(12);
restore_gp_reg(13); restore_gp_reg(14); restore_gp_reg(15);
restore_gp_reg(16); restore_gp_reg(17); restore_gp_reg(18);
restore_gp_reg(19); restore_gp_reg(20); restore_gp_reg(21);
restore_gp_reg(22); restore_gp_reg(23); restore_gp_reg(24);
restore_gp_reg(25); restore_gp_reg(26); restore_gp_reg(27);
restore_gp_reg(28); restore_gp_reg(29); restore_gp_reg(30);
restore_gp_reg(31);
#undef restore_gp_reg
err |= __get_user(used_math, &sc->sc_used_math);
conditional_used_math(used_math);
preempt_disable();
if (used_math()) {
/* restore fpu context if we have used it before */
own_fpu();
err |= restore_fp_context32(sc);
} else {
/* signal handler may have used FPU. Give it up. */
lose_fpu();
}
preempt_enable();
return err;
}
struct sigframe {
u32 sf_ass[4]; /* argument save space for o32 */
#if ICACHE_REFILLS_WORKAROUND_WAR
u32 sf_pad[2];
#else
u32 sf_code[2]; /* signal trampoline */
#endif
struct sigcontext32 sf_sc;
sigset_t sf_mask;
#if ICACHE_REFILLS_WORKAROUND_WAR
u32 sf_code[8] ____cacheline_aligned; /* signal trampoline */
#endif
};
struct rt_sigframe32 {
u32 rs_ass[4]; /* argument save space for o32 */
#if ICACHE_REFILLS_WORKAROUND_WAR
u32 rs_pad[2];
#else
u32 rs_code[2]; /* signal trampoline */
#endif
compat_siginfo_t rs_info;
struct ucontext32 rs_uc;
#if ICACHE_REFILLS_WORKAROUND_WAR
u32 rs_code[8] __attribute__((aligned(32))); /* signal trampoline */
#endif
};
int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from)
{
int err;
if (!access_ok (VERIFY_WRITE, to, sizeof(compat_siginfo_t)))
return -EFAULT;
/* If you change siginfo_t structure, please be sure
this code is fixed accordingly.
It should never copy any pad contained in the structure
to avoid security leaks, but must copy the generic
3 ints plus the relevant union member.
This routine must convert siginfo from 64bit to 32bit as well
at the same time. */
err = __put_user(from->si_signo, &to->si_signo);
err |= __put_user(from->si_errno, &to->si_errno);
err |= __put_user((short)from->si_code, &to->si_code);
if (from->si_code < 0)
err |= __copy_to_user(&to->_sifields._pad, &from->_sifields._pad, SI_PAD_SIZE);
else {
switch (from->si_code >> 16) {
case __SI_TIMER >> 16:
err |= __put_user(from->si_tid, &to->si_tid);
err |= __put_user(from->si_overrun, &to->si_overrun);
err |= __put_user(from->si_int, &to->si_int);
break;
case __SI_CHLD >> 16:
err |= __put_user(from->si_utime, &to->si_utime);
err |= __put_user(from->si_stime, &to->si_stime);
err |= __put_user(from->si_status, &to->si_status);
default:
err |= __put_user(from->si_pid, &to->si_pid);
err |= __put_user(from->si_uid, &to->si_uid);
break;
case __SI_FAULT >> 16:
err |= __put_user((unsigned long)from->si_addr, &to->si_addr);
break;
case __SI_POLL >> 16:
err |= __put_user(from->si_band, &to->si_band);
err |= __put_user(from->si_fd, &to->si_fd);
break;
case __SI_RT >> 16: /* This is not generated by the kernel as of now. */
case __SI_MESGQ >> 16:
err |= __put_user(from->si_pid, &to->si_pid);
err |= __put_user(from->si_uid, &to->si_uid);
err |= __put_user(from->si_int, &to->si_int);
break;
}
}
return err;
}
save_static_function(sys32_sigreturn);
__attribute_used__ noinline static void
_sys32_sigreturn(nabi_no_regargs struct pt_regs regs)
{
struct sigframe __user *frame;
sigset_t blocked;
frame = (struct sigframe __user *) regs.regs[29];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
goto badframe;
sigdelsetmask(&blocked, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
current->blocked = blocked;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
if (restore_sigcontext32(&regs, &frame->sf_sc))
goto badframe;
/*
* Don't let your children do this ...
*/
__asm__ __volatile__(
"move\t$29, %0\n\t"
"j\tsyscall_exit"
:/* no outputs */
:"r" (&regs));
/* Unreached */
badframe:
force_sig(SIGSEGV, current);
}
save_static_function(sys32_rt_sigreturn);
__attribute_used__ noinline static void
_sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
{
struct rt_sigframe32 __user *frame;
mm_segment_t old_fs;
sigset_t set;
stack_t st;
s32 sp;
frame = (struct rt_sigframe32 __user *) regs.regs[29];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
goto badframe;
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
if (restore_sigcontext32(&regs, &frame->rs_uc.uc_mcontext))
goto badframe;
/* The ucontext contains a stack32_t, so we must convert! */
if (__get_user(sp, &frame->rs_uc.uc_stack.ss_sp))
goto badframe;
st.ss_sp = (void __user *)(long) sp;
if (__get_user(st.ss_size, &frame->rs_uc.uc_stack.ss_size))
goto badframe;
if (__get_user(st.ss_flags, &frame->rs_uc.uc_stack.ss_flags))
goto badframe;
/* It is more difficult to avoid calling this function than to
call it and ignore errors. */
old_fs = get_fs();
set_fs (KERNEL_DS);
do_sigaltstack((stack_t __user *)&st, NULL, regs.regs[29]);
set_fs (old_fs);
/*
* Don't let your children do this ...
*/
__asm__ __volatile__(
"move\t$29, %0\n\t"
"j\tsyscall_exit"
:/* no outputs */
:"r" (&regs));
/* Unreached */
badframe:
force_sig(SIGSEGV, current);
}
static inline int setup_sigcontext32(struct pt_regs *regs,
struct sigcontext32 __user *sc)
{
int err = 0;
err |= __put_user(regs->cp0_epc, &sc->sc_pc);
err |= __put_user(regs->cp0_status, &sc->sc_status);
#define save_gp_reg(i) { \
err |= __put_user(regs->regs[i], &sc->sc_regs[i]); \
} while(0)
__put_user(0, &sc->sc_regs[0]); save_gp_reg(1); save_gp_reg(2);
save_gp_reg(3); save_gp_reg(4); save_gp_reg(5); save_gp_reg(6);
save_gp_reg(7); save_gp_reg(8); save_gp_reg(9); save_gp_reg(10);
save_gp_reg(11); save_gp_reg(12); save_gp_reg(13); save_gp_reg(14);
save_gp_reg(15); save_gp_reg(16); save_gp_reg(17); save_gp_reg(18);
save_gp_reg(19); save_gp_reg(20); save_gp_reg(21); save_gp_reg(22);
save_gp_reg(23); save_gp_reg(24); save_gp_reg(25); save_gp_reg(26);
save_gp_reg(27); save_gp_reg(28); save_gp_reg(29); save_gp_reg(30);
save_gp_reg(31);
#undef save_gp_reg
err |= __put_user(regs->hi, &sc->sc_mdhi);
err |= __put_user(regs->lo, &sc->sc_mdlo);
if (cpu_has_dsp) {
err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp);
err |= __put_user(mfhi1(), &sc->sc_hi1);
err |= __put_user(mflo1(), &sc->sc_lo1);
err |= __put_user(mfhi2(), &sc->sc_hi2);
err |= __put_user(mflo2(), &sc->sc_lo2);
err |= __put_user(mfhi3(), &sc->sc_hi3);
err |= __put_user(mflo3(), &sc->sc_lo3);
}
err |= __put_user(!!used_math(), &sc->sc_used_math);
if (!used_math())
goto out;
/*
* Save FPU state to signal context. Signal handler will "inherit"
* current FPU state.
*/
preempt_disable();
if (!is_fpu_owner()) {
own_fpu();
restore_fp(current);
}
err |= save_fp_context32(sc);
preempt_enable();
out:
return err;
}
/*
* Determine which stack to use..
*/
static inline void __user *get_sigframe(struct k_sigaction *ka,
struct pt_regs *regs,
size_t frame_size)
{
unsigned long sp;
/* Default to using normal stack */
sp = regs->regs[29];
/*
* FPU emulator may have it's own trampoline active just
* above the user stack, 16-bytes before the next lowest
* 16 byte boundary. Try to avoid trashing it.
*/
sp -= 32;
/* This is the X/Open sanctioned signal stack switching. */
if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags (sp) == 0))
sp = current->sas_ss_sp + current->sas_ss_size;
return (void __user *)((sp - frame_size) & ALMASK);
}
int setup_frame_32(struct k_sigaction * ka, struct pt_regs *regs,
int signr, sigset_t *set)
{
struct sigframe __user *frame;
int err = 0;
frame = get_sigframe(ka, regs, sizeof(*frame));
if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
goto give_sigsegv;
/*
* Set up the return code ...
*
* li v0, __NR_O32_sigreturn
* syscall
*/
err |= __put_user(0x24020000 + __NR_O32_sigreturn, frame->sf_code + 0);
err |= __put_user(0x0000000c , frame->sf_code + 1);
flush_cache_sigtramp((unsigned long) frame->sf_code);
err |= setup_sigcontext32(regs, &frame->sf_sc);
err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
if (err)
goto give_sigsegv;
/*
* Arguments to signal handler:
*
* a0 = signal number
* a1 = 0 (should be cause)
* a2 = pointer to struct sigcontext
*
* $25 and c0_epc point to the signal handler, $29 points to the
* struct sigframe.
*/
regs->regs[ 4] = signr;
regs->regs[ 5] = 0;
regs->regs[ 6] = (unsigned long) &frame->sf_sc;
regs->regs[29] = (unsigned long) frame;
regs->regs[31] = (unsigned long) frame->sf_code;
regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
#if DEBUG_SIG
printk("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%p\n",
current->comm, current->pid,
frame, regs->cp0_epc, frame->sf_code);
#endif
return 0;
give_sigsegv:
force_sigsegv(signr, current);
return -EFAULT;
}
int setup_rt_frame_32(struct k_sigaction * ka, struct pt_regs *regs,
int signr, sigset_t *set, siginfo_t *info)
{
struct rt_sigframe32 __user *frame;
int err = 0;
s32 sp;
frame = get_sigframe(ka, regs, sizeof(*frame));
if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
goto give_sigsegv;
/* Set up to return from userspace. If provided, use a stub already
in userspace. */
/*
* Set up the return code ...
*
* li v0, __NR_O32_rt_sigreturn
* syscall
*/
err |= __put_user(0x24020000 + __NR_O32_rt_sigreturn, frame->rs_code + 0);
err |= __put_user(0x0000000c , frame->rs_code + 1);
flush_cache_sigtramp((unsigned long) frame->rs_code);
/* Convert (siginfo_t -> compat_siginfo_t) and copy to user. */
err |= copy_siginfo_to_user32(&frame->rs_info, info);
/* Create the ucontext. */
err |= __put_user(0, &frame->rs_uc.uc_flags);
err |= __put_user(0, &frame->rs_uc.uc_link);
sp = (int) (long) current->sas_ss_sp;
err |= __put_user(sp,
&frame->rs_uc.uc_stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->regs[29]),
&frame->rs_uc.uc_stack.ss_flags);
err |= __put_user(current->sas_ss_size,
&frame->rs_uc.uc_stack.ss_size);
err |= setup_sigcontext32(regs, &frame->rs_uc.uc_mcontext);
err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
if (err)
goto give_sigsegv;
/*
* Arguments to signal handler:
*
* a0 = signal number
* a1 = 0 (should be cause)
* a2 = pointer to ucontext
*
* $25 and c0_epc point to the signal handler, $29 points to
* the struct rt_sigframe32.
*/
regs->regs[ 4] = signr;
regs->regs[ 5] = (unsigned long) &frame->rs_info;
regs->regs[ 6] = (unsigned long) &frame->rs_uc;
regs->regs[29] = (unsigned long) frame;
regs->regs[31] = (unsigned long) frame->rs_code;
regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
#if DEBUG_SIG
printk("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%p\n",
current->comm, current->pid,
frame, regs->cp0_epc, frame->rs_code);
#endif
return 0;
give_sigsegv:
force_sigsegv(signr, current);
return -EFAULT;
}
static inline int handle_signal(unsigned long sig, siginfo_t *info,
struct k_sigaction *ka, sigset_t *oldset, struct pt_regs * regs)
{
int ret;
switch (regs->regs[0]) {
case ERESTART_RESTARTBLOCK:
case ERESTARTNOHAND:
regs->regs[2] = EINTR;
break;
case ERESTARTSYS:
if (!(ka->sa.sa_flags & SA_RESTART)) {
regs->regs[2] = EINTR;
break;
}
/* fallthrough */
case ERESTARTNOINTR: /* Userland will reload $v0. */
regs->regs[7] = regs->regs[26];
regs->cp0_epc -= 8;
}
regs->regs[0] = 0; /* Don't deal with this again. */
if (ka->sa.sa_flags & SA_SIGINFO)
ret = current->thread.abi->setup_rt_frame(ka, regs, sig, oldset, info);
else
ret = current->thread.abi->setup_frame(ka, regs, sig, oldset);
spin_lock_irq(&current->sighand->siglock);
sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
if (!(ka->sa.sa_flags & SA_NODEFER))
sigaddset(&current->blocked,sig);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
return ret;
}
void do_signal32(struct pt_regs *regs)
{
struct k_sigaction ka;
sigset_t *oldset;
siginfo_t info;
int signr;
/*
* We want the common case to go fast, which is why we may in certain
* cases get here from kernel mode. Just return without doing anything
* if so.
*/
if (!user_mode(regs))
return;
if (test_thread_flag(TIF_RESTORE_SIGMASK))
oldset = &current->saved_sigmask;
else
oldset = &current->blocked;
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
if (signr > 0) {
/* Whee! Actually deliver the signal. */
if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
/*
* A signal was successfully delivered; the saved
* sigmask will have been stored in the signal frame,
* and will be restored by sigreturn, so we can simply
* clear the TIF_RESTORE_SIGMASK flag.
*/
if (test_thread_flag(TIF_RESTORE_SIGMASK))
clear_thread_flag(TIF_RESTORE_SIGMASK);
}
return;
}
/*
* Who's code doesn't conform to the restartable syscall convention
* dies here!!! The li instruction, a single machine instruction,
* must directly be followed by the syscall instruction.
*/
if (regs->regs[0]) {
if (regs->regs[2] == ERESTARTNOHAND ||
regs->regs[2] == ERESTARTSYS ||
regs->regs[2] == ERESTARTNOINTR) {
regs->regs[7] = regs->regs[26];
regs->cp0_epc -= 8;
}
if (regs->regs[2] == ERESTART_RESTARTBLOCK) {
regs->regs[2] = __NR_O32_restart_syscall;
regs->regs[7] = regs->regs[26];
regs->cp0_epc -= 4;
}
regs->regs[0] = 0; /* Don't deal with this again. */
}
/*
* If there's no signal to deliver, we just put the saved sigmask
* back
*/
if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
clear_thread_flag(TIF_RESTORE_SIGMASK);
sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
}
}
asmlinkage int sys32_rt_sigaction(int sig, const struct sigaction32 __user *act,
struct sigaction32 __user *oact,
unsigned int sigsetsize)
{
struct k_sigaction new_sa, old_sa;
int ret = -EINVAL;
/* XXX: Don't preclude handling different sized sigset_t's. */
if (sigsetsize != sizeof(sigset_t))
goto out;
if (act) {
s32 handler;
int err = 0;
if (!access_ok(VERIFY_READ, act, sizeof(*act)))
return -EFAULT;
err |= __get_user(handler, &act->sa_handler);
new_sa.sa.sa_handler = (void __user *)(s64)handler;
err |= __get_user(new_sa.sa.sa_flags, &act->sa_flags);
err |= get_sigset(&new_sa.sa.sa_mask, &act->sa_mask);
if (err)
return -EFAULT;
}
ret = do_sigaction(sig, act ? &new_sa : NULL, oact ? &old_sa : NULL);
if (!ret && oact) {
int err = 0;
if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)))
return -EFAULT;
err |= __put_user((u32)(u64)old_sa.sa.sa_handler,
&oact->sa_handler);
err |= __put_user(old_sa.sa.sa_flags, &oact->sa_flags);
err |= put_sigset(&old_sa.sa.sa_mask, &oact->sa_mask);
if (err)
return -EFAULT;
}
out:
return ret;
}
asmlinkage int sys32_rt_sigprocmask(int how, compat_sigset_t __user *set,
compat_sigset_t __user *oset, unsigned int sigsetsize)
{
sigset_t old_set, new_set;
int ret;
mm_segment_t old_fs = get_fs();
if (set && get_sigset(&new_set, set))
return -EFAULT;
set_fs (KERNEL_DS);
ret = sys_rt_sigprocmask(how, set ? (sigset_t __user *)&new_set : NULL,
oset ? (sigset_t __user *)&old_set : NULL,
sigsetsize);
set_fs (old_fs);
if (!ret && oset && put_sigset(&old_set, oset))
return -EFAULT;
return ret;
}
asmlinkage int sys32_rt_sigpending(compat_sigset_t __user *uset,
unsigned int sigsetsize)
{
int ret;
sigset_t set;
mm_segment_t old_fs = get_fs();
set_fs (KERNEL_DS);
ret = sys_rt_sigpending((sigset_t __user *)&set, sigsetsize);
set_fs (old_fs);
if (!ret && put_sigset(&set, uset))
return -EFAULT;
return ret;
}
asmlinkage int sys32_rt_sigqueueinfo(int pid, int sig, compat_siginfo_t __user *uinfo)
{
siginfo_t info;
int ret;
mm_segment_t old_fs = get_fs();
if (copy_from_user (&info, uinfo, 3*sizeof(int)) ||
copy_from_user (info._sifields._pad, uinfo->_sifields._pad, SI_PAD_SIZE))
return -EFAULT;
set_fs (KERNEL_DS);
ret = sys_rt_sigqueueinfo(pid, sig, (siginfo_t __user *)&info);
set_fs (old_fs);
return ret;
}
asmlinkage long
sys32_waitid(int which, compat_pid_t pid,
compat_siginfo_t __user *uinfo, int options,
struct compat_rusage __user *uru)
{
siginfo_t info;
struct rusage ru;
long ret;
mm_segment_t old_fs = get_fs();
info.si_signo = 0;
set_fs (KERNEL_DS);
ret = sys_waitid(which, pid, (siginfo_t __user *) &info, options,
uru ? (struct rusage __user *) &ru : NULL);
set_fs (old_fs);
if (ret < 0 || info.si_signo == 0)
return ret;
if (uru && (ret = put_compat_rusage(&ru, uru)))
return ret;
BUG_ON(info.si_code & __SI_MASK);
info.si_code |= __SI_CHLD;
return copy_siginfo_to_user32(uinfo, &info);
}