diff options
| author | Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> | 2014-04-17 17:17:40 +0900 | 
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2014-04-24 10:03:00 +0200 | 
| commit | ecd50f714c421c759354632dd00f70c718c95b10 (patch) | |
| tree | 82fc08180816ee1eb79e92a9060af1a25d1dd802 | |
| parent | 6f6343f53d133bae516caf3d254bce37d8774625 (diff) | |
kprobes, x86: Call exception_enter after kprobes handled
Move exception_enter() call after kprobes handler
is done. Since the exception_enter() involves
many other functions (like printk), it can cause
recursive int3/break loop when kprobes probe such
functions.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Kees Cook <keescook@chromium.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/20140417081740.26341.10894.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | arch/x86/kernel/traps.c | 5 | 
1 files changed, 2 insertions, 3 deletions
| diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index e5d4a70814d7..ba9abe9cbce3 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -327,7 +327,6 @@ dotraplinkage void __kprobes notrace do_int3(struct pt_regs *regs, long error_co  	if (poke_int3_handler(regs))  		return; -	prev_state = exception_enter();  #ifdef CONFIG_KGDB_LOW_LEVEL_TRAP  	if (kgdb_ll_trap(DIE_INT3, "int3", regs, error_code, X86_TRAP_BP,  				SIGTRAP) == NOTIFY_STOP) @@ -338,6 +337,7 @@ dotraplinkage void __kprobes notrace do_int3(struct pt_regs *regs, long error_co  	if (kprobe_int3_handler(regs))  		return;  #endif +	prev_state = exception_enter();  	if (notify_die(DIE_INT3, "int3", regs, error_code, X86_TRAP_BP,  			SIGTRAP) == NOTIFY_STOP) @@ -415,8 +415,6 @@ dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code)  	unsigned long dr6;  	int si_code; -	prev_state = exception_enter(); -  	get_debugreg(dr6, 6);  	/* Filter out all the reserved bits which are preset to 1 */ @@ -449,6 +447,7 @@ dotraplinkage void __kprobes do_debug(struct pt_regs *regs, long error_code)  	if (kprobe_debug_handler(regs))  		goto exit;  #endif +	prev_state = exception_enter();  	if (notify_die(DIE_DEBUG, "debug", regs, (long)&dr6, error_code,  							SIGTRAP) == NOTIFY_STOP) | 
