[PATCH 4.5 62/88] parisc: fix a bug when syscall number of tracee is __NR_Linux_syscalls

From: Greg Kroah-Hartman
Date: Mon May 09 2016 - 03:42:25 EST


4.5-stable review patch. If anyone has any objections, please let me know.

------------------

From: Dmitry V. Levin <ldv@xxxxxxxxxxxx>

commit f0b22d1bb2a37a665a969e95785c75a4f49d1499 upstream.

Do not load one entry beyond the end of the syscall table when the
syscall number of a traced process equals to __NR_Linux_syscalls.
Similar bug with regular processes was fixed by commit 3bb457af4fa8
("[PARISC] Fix bug when syscall nr is __NR_Linux_syscalls").

This bug was found by strace test suite.

Signed-off-by: Dmitry V. Levin <ldv@xxxxxxxxxxxx>
Acked-by: Helge Deller <deller@xxxxxx>
Signed-off-by: Helge Deller <deller@xxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/parisc/kernel/syscall.S | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/parisc/kernel/syscall.S
+++ b/arch/parisc/kernel/syscall.S
@@ -344,7 +344,7 @@ tracesys_next:
#endif

cmpib,COND(=),n -1,%r20,tracesys_exit /* seccomp may have returned -1 */
- comiclr,>>= __NR_Linux_syscalls, %r20, %r0
+ comiclr,>> __NR_Linux_syscalls, %r20, %r0
b,n .Ltracesys_nosys

LDREGX %r20(%r19), %r19