From: Andy Lutomirski Date: Tue, 25 Nov 2014 01:39:06 +0000 (-0800) Subject: x86/asm/traps: Disable tracing and kprobes in fixup_bad_iret and sync_regs X-Git-Tag: v2.6.32.66~48 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f0d8cc6fafe9e747025f067ae77bdb7ddf06144b;p=thirdparty%2Fkernel%2Fstable.git x86/asm/traps: Disable tracing and kprobes in fixup_bad_iret and sync_regs commit 7ddc6a2199f1da405a2fb68c40db8899b1a8cd87 upstream. These functions can be executed on the int3 stack, so kprobes are dangerous. Tracing is probably a bad idea, too. Fixes: b645af2d5905 ("x86_64, traps: Rework bad_iret") Signed-off-by: Andy Lutomirski Cc: Linus Torvalds Cc: Steven Rostedt Link: http://lkml.kernel.org/r/50e33d26adca60816f3ba968875801652507d0c4.1416870125.git.luto@amacapital.net Signed-off-by: Ingo Molnar [bwh: Backported to 3.2: - Use __kprobes instead of NOKPROBE_SYMBOL() - Don't use __visible] Signed-off-by: Ben Hutchings (cherry picked from commit 8ea4c465ecb59846abed3d000d64b21b8e31aeb0) Signed-off-by: Willy Tarreau --- diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 8a39a6c232b32..b999043e823a7 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -493,7 +493,7 @@ dotraplinkage void __kprobes do_int3(struct pt_regs *regs, long error_code) * for scheduling or signal handling. The actual stack switch is done in * entry.S */ -asmlinkage __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs) +asmlinkage notrace __kprobes struct pt_regs *sync_regs(struct pt_regs *eregs) { struct pt_regs *regs = eregs; /* Did already sync */ @@ -518,7 +518,7 @@ struct bad_iret_stack { struct pt_regs regs; }; -asmlinkage +asmlinkage notrace __kprobes struct bad_iret_stack *fixup_bad_iret(struct bad_iret_stack *s) { /*