4.19-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 02106f883cd745523f7766d90a739f983f19e650 ]
Since kprobe breakpoing handler is using bsearch(), probing on this routine can cause recursive breakpoint problem.
int3 ->do_int3() ->ftrace_int3_handler() ->ftrace_location() ->ftrace_location_range() ->bsearch() -> int3
Prohibit probing on bsearch().
Signed-off-by: Andrea Righi righi.andrea@gmail.com Acked-by: Masami Hiramatsu mhiramat@kernel.org Cc: Alexander Shishkin alexander.shishkin@linux.intel.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/154998813406.31052.8791425358974650922.stgit@devbox Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- lib/bsearch.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/lib/bsearch.c b/lib/bsearch.c index 18b445b010c3..82512fe7b33c 100644 --- a/lib/bsearch.c +++ b/lib/bsearch.c @@ -11,6 +11,7 @@
#include <linux/export.h> #include <linux/bsearch.h> +#include <linux/kprobes.h>
/* * bsearch - binary search an array of elements @@ -53,3 +54,4 @@ void *bsearch(const void *key, const void *base, size_t num, size_t size, return NULL; } EXPORT_SYMBOL(bsearch); +NOKPROBE_SYMBOL(bsearch);