diff options
| author | Masami Hiramatsu <mhiramat@redhat.com> | 2009-02-05 17:12:39 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-02-12 09:50:24 -0800 |
| commit | 5f1d5882000a8d13f244165ae8747029958ab3df (patch) | |
| tree | c7292ba4ec1016c25b692355b6ccbe0d986ec293 | |
| parent | ad649a5df5b1d4e1feb3f03fc452d05ad217e339 (diff) | |
prevent kprobes from catching spurious page faults
commit 9be260a646bf76fa418ee519afa10196b3164681 upstream.
Prevent kprobes from catching spurious faults which will cause infinite
recursive page-fault and memory corruption by stack overflow.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | arch/x86/mm/fault.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 46f4cb168ac2..68dc0609b896 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -601,8 +601,6 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) si_code = SEGV_MAPERR; - if (notify_page_fault(regs)) - return; if (unlikely(kmmio_fault(regs, address))) return; @@ -632,6 +630,9 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) if (spurious_fault(address, error_code)) return; + /* kprobes don't want to hook the spurious faults. */ + if (notify_page_fault(regs)) + return; /* * Don't take the mm semaphore here. If we fixup a prefetch * fault we could otherwise deadlock. @@ -639,6 +640,9 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) goto bad_area_nosemaphore; } + /* kprobes don't want to hook the spurious faults. */ + if (notify_page_fault(regs)) + return; /* * It's safe to allow irq's after cr2 has been saved and the |