kprobes: Prohibit probing on preemption checking debug functions

Since kprobes depends on preempt disable/enable, probing
on the preempt debug routines can cause recursive breakpoint
bugs.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/154998804911.31052.3541963527929117920.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Masami Hiramatsu 2019-02-13 01:14:09 +09:00 committed by Ingo Molnar
parent eeeb080bae
commit 984640ce42

View File

@ -5,10 +5,11 @@
* DEBUG_PREEMPT variant of smp_processor_id().
*/
#include <linux/export.h>
#include <linux/kprobes.h>
#include <linux/sched.h>
notrace static unsigned int check_preemption_disabled(const char *what1,
const char *what2)
notrace static nokprobe_inline
unsigned int check_preemption_disabled(const char *what1, const char *what2)
{
int this_cpu = raw_smp_processor_id();
@ -56,9 +57,11 @@ notrace unsigned int debug_smp_processor_id(void)
return check_preemption_disabled("smp_processor_id", "");
}
EXPORT_SYMBOL(debug_smp_processor_id);
NOKPROBE_SYMBOL(debug_smp_processor_id);
notrace void __this_cpu_preempt_check(const char *op)
{
check_preemption_disabled("__this_cpu_", op);
}
EXPORT_SYMBOL(__this_cpu_preempt_check);
NOKPROBE_SYMBOL(__this_cpu_preempt_check);