diff options
author | Michael Neuling <mikey@neuling.org> | 2013-12-16 15:12:43 +1100 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-01-09 12:24:22 -0800 |
commit | 4e639053aacb787a762e3dea49f4d3a6c13a52e7 (patch) | |
tree | da3fcafdef54b150b414883d55a5a318c385bab6 /arch/arm | |
parent | 9e23c5bb1507d413f86652feea3fb1c41cb6f99b (diff) |
powerpc: Fix bad stack check in exception entry
commit 90ff5d688e61f49f23545ffab6228bd7e87e6dc7 upstream.
In EXCEPTION_PROLOG_COMMON() we check to see if the stack pointer (r1)
is valid when coming from the kernel. If it's not valid, we die but
with a nice oops message.
Currently we allocate a stack frame (subtract INT_FRAME_SIZE) before we
check to see if the stack pointer is negative. Unfortunately, this
won't detect a bad stack where r1 is less than INT_FRAME_SIZE.
This patch fixes the check to compare the modified r1 with
-INT_FRAME_SIZE. With this, bad kernel stack pointers (including NULL
pointers) are correctly detected again.
Kudos to Paulus for finding this.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/arm')
0 files changed, 0 insertions, 0 deletions