android_kernel_xiaomi_sm8350/arch/mips/kernel/signal_n32.c
Al Viro 4bfb8c5c87 MIPS: do_sigaltstack() expects userland pointers
o32 compat does the right thing, native and n32 compat do not...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-kernel@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/1700/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-10-18 16:59:03 +01:00

231 lines
6.3 KiB
C

/*
* Copyright (C) 2003 Broadcom Corporation
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <linux/cache.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/errno.h>
#include <linux/wait.h>
#include <linux/ptrace.h>
#include <linux/unistd.h>
#include <linux/compat.h>
#include <linux/bitops.h>
#include <asm/abi.h>
#include <asm/asm.h>
#include <asm/cacheflush.h>
#include <asm/compat-signal.h>
#include <asm/sim.h>
#include <asm/uaccess.h>
#include <asm/ucontext.h>
#include <asm/system.h>
#include <asm/fpu.h>
#include <asm/cpu-features.h>
#include <asm/war.h>
#include <asm/vdso.h>
#include "signal-common.h"
/*
* Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
*/
#define __NR_N32_restart_syscall 6214
extern int setup_sigcontext(struct pt_regs *, struct sigcontext __user *);
extern int restore_sigcontext(struct pt_regs *, struct sigcontext __user *);
/* IRIX compatible stack_t */
typedef struct sigaltstack32 {
s32 ss_sp;
compat_size_t ss_size;
int ss_flags;
} stack32_t;
struct ucontextn32 {
u32 uc_flags;
s32 uc_link;
stack32_t uc_stack;
struct sigcontext uc_mcontext;
compat_sigset_t uc_sigmask; /* mask last for extensibility */
};
struct rt_sigframe_n32 {
u32 rs_ass[4]; /* argument save space for o32 */
u32 rs_pad[2]; /* Was: signal trampoline */
struct compat_siginfo rs_info;
struct ucontextn32 rs_uc;
};
extern void sigset_from_compat(sigset_t *set, compat_sigset_t *compat);
asmlinkage int sysn32_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)
{
compat_sigset_t __user *unewset;
compat_sigset_t uset;
size_t sigsetsize;
sigset_t newset;
/* XXX Don't preclude handling different sized sigset_t's. */
sigsetsize = regs.regs[5];
if (sigsetsize != sizeof(sigset_t))
return -EINVAL;
unewset = (compat_sigset_t __user *) regs.regs[4];
if (copy_from_user(&uset, unewset, sizeof(uset)))
return -EFAULT;
sigset_from_compat(&newset, &uset);
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 void sysn32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
{
struct rt_sigframe_n32 __user *frame;
mm_segment_t old_fs;
sigset_t set;
stack_t st;
s32 sp;
int sig;
frame = (struct rt_sigframe_n32 __user *) regs.regs[29];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask))
goto badframe;
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
sig = restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext);
if (sig < 0)
goto badframe;
else if (sig)
force_sig(sig, current);
/* 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 int setup_rt_frame_n32(void *sig_return, struct k_sigaction *ka,
struct pt_regs *regs, int signr, sigset_t *set, siginfo_t *info)
{
struct rt_sigframe_n32 __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;
/* Create siginfo. */
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_sigcontext(regs, &frame->rs_uc.uc_mcontext);
err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, 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_sigframe.
*/
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) sig_return;
regs->cp0_epc = regs->regs[25] = (unsigned long) ka->sa.sa_handler;
DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n",
current->comm, current->pid,
frame, regs->cp0_epc, regs->regs[31]);
return 0;
give_sigsegv:
force_sigsegv(signr, current);
return -EFAULT;
}
struct mips_abi mips_abi_n32 = {
.setup_rt_frame = setup_rt_frame_n32,
.rt_signal_return_offset =
offsetof(struct mips_vdso, n32_rt_signal_trampoline),
.restart = __NR_N32_restart_syscall
};