Commit-ID: 8101376dc5f42bd93b36d4ab210b44503d0ec11f Gitweb: http://git.kernel.org/tip/8101376dc5f42bd93b36d4ab210b44503d0ec11f Author: Masami Hiramatsu <[email protected]> AuthorDate: Thu, 4 Apr 2013 19:42:30 +0900 Committer: Ingo Molnar <[email protected]> CommitDate: Mon, 8 Apr 2013 17:28:34 +0200
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 <[email protected]> Cc: Frank Ch. Eigler <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/20130404104230.22862.85242.stgit@mhiramat-M0-7522 Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/kernel/kprobes/core.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index 7bfe318..9895a9a 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; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
