path: root/arch
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authorLinus Torvalds <torvalds@linux-foundation.org>2010-08-13 09:49:20 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-08-13 09:49:20 -0700
commit96054569190bdec375fe824e48ca1f4e3b53dd36 (patch)
tree13e249da75a0667e2c9d195e9c125fb14d721e71 /arch
parent5528f9132cf65d4d892bcbc5684c61e7822b21e9 (diff)
x86: don't send SIGBUS for kernel page faults
It's wrong for several reasons, but the most direct one is that the fault may be for the stack accesses to set up a previous SIGBUS. When we have a kernel exception, the kernel exception handler does all the fixups, not some user-level signal handler. Even apart from the nested SIGBUS issue, it's also wrong to give out kernel fault addresses in the signal handler info block, or to send a SIGBUS when a system call already returns EFAULT. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch')
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index f62777940dfb..4c4508e8a204 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -802,8 +802,10 @@ do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address,
/* Kernel mode? Handle exceptions or die: */
- if (!(error_code & PF_USER))
+ if (!(error_code & PF_USER)) {
no_context(regs, error_code, address);
+ return;
+ }
/* User-space => ok to do another page fault: */
if (is_prefetch(regs, error_code, address))

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