diff options
| author | Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> | 2013-04-04 19:42:30 +0900 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2013-04-08 17:28:34 +0200 |
| commit | 8101376dc5f42bd93b36d4ab210b44503d0ec11f (patch) | |
| tree | 7adb1e6a9ab280da5ce3e4fdc4f1e6fc42a2b4db | |
| parent | 324670b620ab1ed00ba160e435686bd2ae4a59ce (diff) | |
kprobes/x86: Just return error for sanity check failure instead of using BUG_ON
Return an error from __copy_instruction() and use printk() to
give us a more productive message, since this is just an error
case which we can handle and also the BUG_ON() never tells us
why and what happened.
This is related to the following bug-report:
https://bugzilla.redhat.com/show_bug.cgi?id=910649
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20130404104230.22862.85242.stgit@mhiramat-M0-7522
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | arch/x86/kernel/kprobes/core.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index 7bfe318d3d8..9895a9a4138 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -353,7 +353,11 @@ int __kprobes __copy_instruction(u8 *dest, u8 *src) * have given. */ newdisp = (u8 *) src + (s64) insn.displacement.value - (u8 *) dest; - BUG_ON((s64) (s32) newdisp != newdisp); /* Sanity check. */ + if ((s64) (s32) newdisp != newdisp) { + pr_err("Kprobes error: new displacement does not fit into s32 (%llx)\n", newdisp); + pr_err("\tSrc: %p, Dest: %p, old disp: %x\n", src, dest, insn.displacement.value); + return 0; + } disp = (u8 *) dest + insn_offset_displacement(&insn); *(s32 *) disp = (s32) newdisp; } |