diff options
| author | Eric W. Biederman <ebiederm@xmission.com> | 2021-10-20 12:43:51 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-11-17 09:48:24 +0100 |
| commit | 625c3ed247e15bfe9e26294cbcf810f6a84d3812 (patch) | |
| tree | 73bff525a1d7e1198a24fc1c7aa03a8a799fc98d /arch | |
| parent | ec5ef8d4d7954d570d1a018677cb4cb0ffbf00cf (diff) | |
signal/mips: Update (_save|_restore)_fp_context to fail with -EFAULT
commit 95bf9d646c3c3f95cb0be7e703b371db8da5be68 upstream.
When an instruction to save or restore a register from the stack fails
in _save_fp_context or _restore_fp_context return with -EFAULT. This
change was made to r2300_fpu.S[1] but it looks like it got lost with
the introduction of EX2[2]. This is also what the other implementation
of _save_fp_context and _restore_fp_context in r4k_fpu.S does, and
what is needed for the callers to be able to handle the error.
Furthermore calling do_exit(SIGSEGV) from bad_stack is wrong because
it does not terminate the entire process it just terminates a single
thread.
As the changed code was the only caller of arch/mips/kernel/syscall.c:bad_stack
remove the problematic and now unused helper function.
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Maciej Rozycki <macro@orcam.me.uk>
Cc: linux-mips@vger.kernel.org
[1] 35938a00ba86 ("MIPS: Fix ISA I FP sigcontext access violation handling")
[2] f92722dc4545 ("MIPS: Correct MIPS I FP sigcontext layout")
Cc: stable@vger.kernel.org
Fixes: f92722dc4545 ("MIPS: Correct MIPS I FP sigcontext layout")
Acked-by: Maciej W. Rozycki <macro@orcam.me.uk>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Link: https://lkml.kernel.org/r/20211020174406.17889-5-ebiederm@xmission.com
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/mips/kernel/r2300_fpu.S | 4 | ||||
| -rw-r--r-- | arch/mips/kernel/syscall.c | 9 |
2 files changed, 2 insertions, 11 deletions
diff --git a/arch/mips/kernel/r2300_fpu.S b/arch/mips/kernel/r2300_fpu.S index 12e58053544f..cbf6db98cfb3 100644 --- a/arch/mips/kernel/r2300_fpu.S +++ b/arch/mips/kernel/r2300_fpu.S @@ -29,8 +29,8 @@ #define EX2(a,b) \ 9: a,##b; \ .section __ex_table,"a"; \ - PTR 9b,bad_stack; \ - PTR 9b+4,bad_stack; \ + PTR 9b,fault; \ + PTR 9b+4,fault; \ .previous .set mips1 diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c index 3f16f3823031..9a28e79f2e66 100644 --- a/arch/mips/kernel/syscall.c +++ b/arch/mips/kernel/syscall.c @@ -239,12 +239,3 @@ SYSCALL_DEFINE3(cachectl, char *, addr, int, nbytes, int, op) { return -ENOSYS; } - -/* - * If we ever come here the user sp is bad. Zap the process right away. - * Due to the bad stack signaling wouldn't work. - */ -asmlinkage void bad_stack(void) -{ - do_exit(SIGSEGV); -} |