diff options
| author | Bogdan Purcareata <bogdan.purcareata@freescale.com> | 2015-03-18 14:03:51 (GMT) |
|---|---|---|
| committer | Honghua Yin <Hong-Hua.Yin@freescale.com> | 2015-03-30 05:12:52 (GMT) |
| commit | 3d4d72b9459396876e1debbb59abcd585283f433 (patch) | |
| tree | b8cc399024cb019e55b8e4a9e17dee2947d90139 /arch | |
| parent | be8d5995081dcfb5487b040d2804cb721efbc219 (diff) | |
| download | linux-fsl-qoriq-3d4d72b9459396876e1debbb59abcd585283f433.tar.xz | |
powerpc: Don't force ENOSYS as error on syscall fail
In certain scenarios - e.g. seccomp filtering with ERRNO as default action -
the system call fails for other reasons than the syscall not being available.
The seccomp filter can be configured to store a user-defined error code on
return from a blacklisted syscall. Don't always set ENOSYS on
do_syscall_trace_enter failure.
Delegate setting ENOSYS in case of failure, where appropriate, to
do_syscall_trace_enter.
v4:
- update syscall_exit to be local label on 64bit, after rebasing on top of 3.19
v3:
- keep setting ENOSYS in the syscall entry assembly for scenarios without
syscall tracing
v2:
- move setting ENOSYS as errno from the syscall entry assembly to
do_syscall_trace_enter, only in the specific case
Upstream-Status: Pending [https://lkml.org/lkml/2015/2/18/50]
Signed-off-by: Bogdan Purcareata <bogdan.purcareata@freescale.com>
Change-Id: I938a8754407a60c79fe9485cc76a6ec891e08e82
Reviewed-on: http://git.am.freescale.net:8181/33030
Reviewed-by: Scott Wood <scottwood@freescale.com>
Tested-by: Honghua Yin <Hong-Hua.Yin@freescale.com>
Reviewed-by: Honghua Yin <Hong-Hua.Yin@freescale.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/entry_32.S | 7 | ||||
| -rw-r--r-- | arch/powerpc/kernel/entry_64.S | 5 | ||||
| -rw-r--r-- | arch/powerpc/kernel/ptrace.c | 4 |
3 files changed, 12 insertions, 4 deletions
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index 59848e5..23e51af 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -339,12 +339,12 @@ _GLOBAL(DoSyscall) lwz r11,TI_FLAGS(r10) andi. r11,r11,_TIF_SYSCALL_T_OR_A bne- syscall_dotrace -syscall_dotrace_cont: cmplwi 0,r0,NR_syscalls lis r10,sys_call_table@h ori r10,r10,sys_call_table@l slwi r0,r0,2 bge- 66f +syscall_dotrace_cont: lwzx r10,r10,r0 /* Fetch system call handler [ptr] */ mtlr r10 addi r9,r1,STACK_FRAME_OVERHEAD @@ -466,6 +466,11 @@ syscall_dotrace: lwz r7,GPR7(r1) lwz r8,GPR8(r1) REST_NVGPRS(r1) + cmplwi 0,r0,NR_syscalls + lis r10,sys_call_table@h + ori r10,r10,sys_call_table@l + slwi r0,r0,2 + bge- ret_from_syscall b syscall_dotrace_cont syscall_exit_work: diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 24f0cf3..2e2de31 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -153,7 +153,6 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR) ld r10,TI_FLAGS(r11) andi. r11,r10,_TIF_SYSCALL_T_OR_A bne syscall_dotrace -.Lsyscall_dotrace_cont: cmpldi 0,r0,NR_syscalls bge- syscall_enosys @@ -266,7 +265,9 @@ syscall_dotrace: addi r9,r1,STACK_FRAME_OVERHEAD CURRENT_THREAD_INFO(r10, r1) ld r10,TI_FLAGS(r10) - b .Lsyscall_dotrace_cont + cmpldi 0,r0,NR_syscalls + bge- .Lsyscall_exit + b system_call syscall_enosys: li r3,-ENOSYS diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index 100e01c..ed1f0fb 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -1775,13 +1775,15 @@ long do_syscall_trace_enter(struct pt_regs *regs) secure_computing_strict(regs->gpr[0]); if (test_thread_flag(TIF_SYSCALL_TRACE) && - tracehook_report_syscall_entry(regs)) + tracehook_report_syscall_entry(regs)) { /* * Tracing decided this syscall should not happen. * We'll return a bogus call number to get an ENOSYS * error, but leave the original number in regs->gpr[0]. */ ret = -1L; + syscall_set_return_value(current, regs, ENOSYS, 0); + } if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) trace_sys_enter(regs, regs->gpr[0]); |