diff options
author | Markos Chandras <markos.chandras@imgtec.com> | 2015-09-25 08:17:42 +0100 |
---|---|---|
committer | Ralf Baechle <ralf@linux-mips.org> | 2015-10-04 12:10:56 +0200 |
commit | d218af78492a36a4ae607c08fedfb59258440314 (patch) | |
tree | fb9a1d1c08161c39c6f8b8db04b0cc116959718b /arch/mips/kernel/scall64-o32.S | |
parent | 66803dd9198cb57a4b7ed4a6846a63ab1d59a2e0 (diff) |
MIPS: scall: Always run the seccomp syscall filters
The MIPS syscall handler code used to return -ENOSYS on invalid
syscalls. Whilst this is expected, it caused problems for seccomp
filters because the said filters never had the change to run since
the code returned -ENOSYS before triggering them. This caused
problems on the chromium testsuite for filters looking for invalid
syscalls. This has now changed and the seccomp filters are always
run even if the syscall is invalid. We return -ENOSYS once we
return from the seccomp filters. Moreover, similar codepaths have
been merged in the process which simplifies somewhat the overall
syscall code.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11236/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/kernel/scall64-o32.S')
-rw-r--r-- | arch/mips/kernel/scall64-o32.S | 19 |
1 files changed, 5 insertions, 14 deletions
diff --git a/arch/mips/kernel/scall64-o32.S b/arch/mips/kernel/scall64-o32.S index 6622980d82ea..6369cfd390c6 100644 --- a/arch/mips/kernel/scall64-o32.S +++ b/arch/mips/kernel/scall64-o32.S @@ -87,6 +87,7 @@ loads_done: and t0, t1, t0 bnez t0, trace_a_syscall +syscall_common: jalr t2 # Do The Real Thing (TM) li t0, -EMAXERRNO - 1 # error? @@ -130,9 +131,9 @@ trace_a_syscall: 1: jal syscall_trace_enter - bltz v0, 2f # seccomp failed? Skip syscall + bltz v0, 1f # seccomp failed? Skip syscall - move t0, s0 + move t2, s0 RESTORE_STATIC ld a0, PT_R4(sp) # Restore argument registers ld a1, PT_R5(sp) @@ -142,19 +143,9 @@ trace_a_syscall: ld a5, PT_R9(sp) ld a6, PT_R10(sp) ld a7, PT_R11(sp) # For indirect syscalls - jalr t0 + j syscall_common - li t0, -EMAXERRNO - 1 # error? - sltu t0, t0, v0 - sd t0, PT_R7(sp) # set error flag - beqz t0, 1f - - ld t1, PT_R2(sp) # syscall number - dnegu v0 # error - sd t1, PT_R0(sp) # save it for syscall restarting -1: sd v0, PT_R2(sp) # result - -2: j syscall_exit +1: j syscall_exit /* ------------------------------------------------------------------------ */ |