diff options
| author | Yong Zhang <yong.zhang@windriver.com> | 2011-08-16 09:54:54 +0800 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2011-09-21 17:53:44 +0200 |
| commit | 1eec6cd08b4feb72a73aff468ab72bdd21e1dc61 (patch) | |
| tree | 70278d81550236b2dc57ddb52b3fc3380fe0c5d9 | |
| parent | b8ecf341f1b7ca7bf3cb80c48cbbae33b79947d0 (diff) | |
MIPS: Compat: Use 32-bit wrapper for compat_sys_futex.
We can't trust userspace to pass signed-extend arguments. Not correctly
sign-extended arguments to futex-wait result in architecturally undefined
operation of 32-bit arithmetic instructions.
For example, if 'val' is too big and bit-31 is 1, the caller may enter
endless loop at:
futex_wait_setup()
{
...
if (uval != val) {
queue_unlock(q, *hb);
ret = -EWOULDBLOCK;
...
}
Signed-off-by: Yong Zhang <yong.zhang@windriver.com>
To: linux-mips@linux-mips.org
To: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/2714/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| -rw-r--r-- | arch/mips/kernel/linux32.c | 7 | ||||
| -rw-r--r-- | arch/mips/kernel/scall64-n32.S | 2 | ||||
| -rw-r--r-- | arch/mips/kernel/scall64-o32.S | 2 |
3 files changed, 9 insertions, 2 deletions
diff --git a/arch/mips/kernel/linux32.c b/arch/mips/kernel/linux32.c index 876a75cc376..922a554cd10 100644 --- a/arch/mips/kernel/linux32.c +++ b/arch/mips/kernel/linux32.c @@ -349,3 +349,10 @@ SYSCALL_DEFINE6(32_fanotify_mark, int, fanotify_fd, unsigned int, flags, return sys_fanotify_mark(fanotify_fd, flags, merge_64(a3, a4), dfd, pathname); } + +SYSCALL_DEFINE6(32_futex, u32 __user *, uaddr, int, op, u32, val, + struct compat_timespec __user *, utime, u32 __user *, uaddr2, + u32, val3) +{ + return compat_sys_futex(uaddr, op, val, utime, uaddr2, val3); +} diff --git a/arch/mips/kernel/scall64-n32.S b/arch/mips/kernel/scall64-n32.S index f9296e894e4..6de1f598346 100644 --- a/arch/mips/kernel/scall64-n32.S +++ b/arch/mips/kernel/scall64-n32.S @@ -315,7 +315,7 @@ EXPORT(sysn32_call_table) PTR sys_fremovexattr PTR sys_tkill PTR sys_ni_syscall - PTR compat_sys_futex + PTR sys_32_futex PTR compat_sys_sched_setaffinity /* 6195 */ PTR compat_sys_sched_getaffinity PTR sys_cacheflush diff --git a/arch/mips/kernel/scall64-o32.S b/arch/mips/kernel/scall64-o32.S index 4d7c9827706..1d813169e45 100644 --- a/arch/mips/kernel/scall64-o32.S +++ b/arch/mips/kernel/scall64-o32.S @@ -441,7 +441,7 @@ sys_call_table: PTR sys_fremovexattr /* 4235 */ PTR sys_tkill PTR sys_sendfile64 - PTR compat_sys_futex + PTR sys_32_futex PTR compat_sys_sched_setaffinity PTR compat_sys_sched_getaffinity /* 4240 */ PTR compat_sys_io_setup |