Files
linux/arch/mips
Aurelien Jarno 7662e48478 MIPS: scall64-o32: Fix indirect syscall number load
commit 79b4a9cf0e upstream.

Commit 4c21b8fd8f (MIPS: seccomp: Handle indirect system calls (o32))
added indirect syscall detection for O32 processes running on MIPS64,
but it did not work correctly for big endian kernel/processes. The
reason is that the syscall number is loaded from ARG1 using the lw
instruction while this is a 64-bit value, so zero is loaded instead of
the syscall number.

Fix the code by using the ld instruction instead. When running a 32-bit
processes on a 64 bit CPU, the values are properly sign-extended, so it
ensures the value passed to syscall_trace_enter is correct.

Recent systemd versions with seccomp enabled whitelist the getpid
syscall for their internal  processes (e.g. systemd-journald), but call
it through syscall(SYS_getpid). This fix therefore allows O32 big endian
systems with a 64-bit kernel to run recent systemd versions.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Cc: <stable@vger.kernel.org> # v3.15+
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-15 12:34:59 +09:00
..
2023-05-15 08:19:16 +09:00
2016-10-06 17:31:02 +02:00
2016-08-03 08:16:30 +02:00
2016-04-03 12:32:09 +02:00
2023-05-15 11:44:20 +09:00
2023-05-15 08:19:35 +09:00
2016-05-28 12:35:09 +02:00
2016-05-28 12:35:09 +02:00
2015-11-11 08:36:36 +01:00
2016-11-04 00:37:15 +01:00