Skip to content

Commit

Permalink
[MIPS] Fix sigset_t endianess swapping issues in 32-bit compat code.
Browse files Browse the repository at this point in the history
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
  • Loading branch information
Ralf Baechle committed Feb 13, 2007
1 parent 366d6ae commit 431dc80
Show file tree
Hide file tree
Showing 6 changed files with 115 additions and 9 deletions.
47 changes: 47 additions & 0 deletions arch/mips/kernel/linux32.c
Original file line number Diff line number Diff line change
Expand Up @@ -39,6 +39,7 @@
#include <net/sock.h>
#include <net/scm.h>

#include <asm/compat-signal.h>
#include <asm/ipc.h>
#include <asm/sim.h>
#include <asm/uaccess.h>
Expand Down Expand Up @@ -736,3 +737,49 @@ _sys32_clone(nabi_no_regargs struct pt_regs regs)
return do_fork(clone_flags, newsp, &regs, 0,
parent_tidptr, child_tidptr);
}

/*
* Implement the event wait interface for the eventpoll file. It is the kernel
* part of the user space epoll_pwait(2).
*/
asmlinkage long compat_sys_epoll_pwait(int epfd,
struct epoll_event __user *events, int maxevents, int timeout,
const compat_sigset_t __user *sigmask, size_t sigsetsize)
{
int error;
sigset_t ksigmask, sigsaved;

/*
* If the caller wants a certain signal mask to be set during the wait,
* we apply it here.
*/
if (sigmask) {
if (sigsetsize != sizeof(sigset_t))
return -EINVAL;
if (!access_ok(VERIFY_READ, sigmask, sizeof(ksigmask)))
return -EFAULT;
if (__copy_conv_sigset_from_user(&ksigmask, sigmask))
return -EFAULT;
sigdelsetmask(&ksigmask, sigmask(SIGKILL) | sigmask(SIGSTOP));
sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
}

error = sys_epoll_wait(epfd, events, maxevents, timeout);

/*
* If we changed the signal mask, we need to restore the original one.
* In case we've got a signal while waiting, we do not restore the
* signal mask yet, and we allow do_signal() to deliver the signal on
* the way back to userspace, before the signal mask is restored.
*/
if (sigmask) {
if (error == -EINTR) {
memcpy(&current->saved_sigmask, &sigsaved,
sizeof(sigsaved));
set_thread_flag(TIF_RESTORE_SIGMASK);
} else
sigprocmask(SIG_SETMASK, &sigsaved, NULL);
}

return error;
}
2 changes: 1 addition & 1 deletion arch/mips/kernel/scall64-64.S
Original file line number Diff line number Diff line change
Expand Up @@ -470,4 +470,4 @@ sys_call_table:
PTR sys_get_robust_list
PTR sys_kexec_load /* 5270 */
PTR sys_getcpu
PTR sys_epoll_pwait
PTR compat_sys_epoll_pwait
2 changes: 1 addition & 1 deletion arch/mips/kernel/scall64-n32.S
Original file line number Diff line number Diff line change
Expand Up @@ -396,4 +396,4 @@ EXPORT(sysn32_call_table)
PTR compat_sys_get_robust_list
PTR compat_sys_kexec_load
PTR sys_getcpu
PTR sys_epoll_pwait
PTR compat_sys_epoll_pwait
11 changes: 7 additions & 4 deletions arch/mips/kernel/signal32.c
Original file line number Diff line number Diff line change
Expand Up @@ -8,6 +8,7 @@
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
*/
#include <linux/cache.h>
#include <linux/compat.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
Expand All @@ -24,6 +25,7 @@

#include <asm/abi.h>
#include <asm/asm.h>
#include <asm/compat-signal.h>
#include <linux/bitops.h>
#include <asm/cacheflush.h>
#include <asm/sim.h>
Expand Down Expand Up @@ -517,7 +519,7 @@ asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs)
frame = (struct sigframe32 __user *) regs.regs[29];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
if (__copy_conv_sigset_from_user(&blocked, &frame->sf_mask))
goto badframe;

sigdelsetmask(&blocked, ~_BLOCKABLE);
Expand Down Expand Up @@ -554,7 +556,7 @@ asmlinkage void sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
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)))
if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask))
goto badframe;

sigdelsetmask(&set, ~_BLOCKABLE);
Expand Down Expand Up @@ -609,7 +611,8 @@ int setup_frame_32(struct k_sigaction * ka, struct pt_regs *regs,
err |= install_sigtramp(frame->sf_code, __NR_O32_sigreturn);

err |= setup_sigcontext32(regs, &frame->sf_sc);
err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set));
err |= __copy_conv_sigset_to_user(&frame->sf_mask, set);

if (err)
goto give_sigsegv;

Expand Down Expand Up @@ -668,7 +671,7 @@ int setup_rt_frame_32(struct k_sigaction * ka, struct pt_regs *regs,
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));
err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set);

if (err)
goto give_sigsegv;
Expand Down
7 changes: 4 additions & 3 deletions arch/mips/kernel/signal_n32.c
Original file line number Diff line number Diff line change
Expand Up @@ -31,6 +31,7 @@

#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>
Expand Down Expand Up @@ -63,7 +64,7 @@ struct ucontextn32 {
s32 uc_link;
stack32_t uc_stack;
struct sigcontext uc_mcontext;
sigset_t uc_sigmask; /* mask last for extensibility */
compat_sigset_t uc_sigmask; /* mask last for extensibility */
};

#if ICACHE_REFILLS_WORKAROUND_WAR == 0
Expand Down Expand Up @@ -129,7 +130,7 @@ asmlinkage void sysn32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
frame = (struct rt_sigframe_n32 __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)))
if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask))
goto badframe;

sigdelsetmask(&set, ~_BLOCKABLE);
Expand Down Expand Up @@ -195,7 +196,7 @@ int setup_rt_frame_n32(struct k_sigaction * ka,
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_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
err |= __copy_conv_sigset_to_user(&frame->rs_uc.uc_sigmask, set);

if (err)
goto give_sigsegv;
Expand Down
55 changes: 55 additions & 0 deletions include/asm-mips/compat-signal.h
Original file line number Diff line number Diff line change
@@ -0,0 +1,55 @@
#ifndef __ASM_COMPAT_SIGNAL_H
#define __ASM_COMPAT_SIGNAL_H

#include <linux/bug.h>
#include <linux/compat.h>
#include <linux/compiler.h>

static inline int __copy_conv_sigset_to_user(compat_sigset_t __user *d,
const sigset_t *s)
{
int err;

BUG_ON(sizeof(*d) != sizeof(*s));
BUG_ON(_NSIG_WORDS != 2);

err = __put_user(s->sig[0], &d->sig[0]);
err |= __put_user(s->sig[0] >> 32, &d->sig[1]);
err |= __put_user(s->sig[1], &d->sig[2]);
err |= __put_user(s->sig[1] >> 32, &d->sig[3]);

return err;
}

static inline int __copy_conv_sigset_from_user(sigset_t *d,
const compat_sigset_t __user *s)
{
int err;
union sigset_u {
sigset_t s;
compat_sigset_t c;
} *u = (union sigset_u *) d;

BUG_ON(sizeof(*d) != sizeof(*s));
BUG_ON(_NSIG_WORDS != 2);

if (unlikely(!access_ok(VERIFY_READ, d, sizeof(*d))))
return -EFAULT;

#ifdef CONFIG_CPU_BIG_ENDIAN
err = __get_user(u->c.sig[1], &s->sig[0]);
err |= __get_user(u->c.sig[0], &s->sig[1]);
err |= __get_user(u->c.sig[3], &s->sig[2]);
err |= __get_user(u->c.sig[2], &s->sig[3]);
#endif
#ifdef CONFIG_CPU_LITTLE_ENDIAN
err = __get_user(u->c.sig[0], &s->sig[0]);
err |= __get_user(u->c.sig[1], &s->sig[1]);
err |= __get_user(u->c.sig[2], &s->sig[2]);
err |= __get_user(u->c.sig[3], &s->sig[3]);
#endif

return err;
}

#endif /* __ASM_COMPAT_SIGNAL_H */

0 comments on commit 431dc80

Please sign in to comment.