From 8a2efd6dd586ef0ff532180e6335ec21310c2cd5 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 14 Feb 2017 15:28:41 -0300 Subject: [PATCH] perf probe: Avoid accessing uninitialized 'map' variable Genuine problem detected with clang, the warnings are spot on: util/probe-event.c:2079:7: error: variable 'map' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized] if (addr) { ^~~~ util/probe-event.c:2094:6: note: uninitialized use occurs here if (map && !is_kprobe) { ^~~ util/probe-event.c:2079:3: note: remove the 'if' if its condition is always true if (addr) { ^~~~~~~~~~ util/probe-event.c:2075:8: error: variable 'map' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized] if (kernel_get_symbol_address_by_name(tp->symbol, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ util/probe-event.c:2094:6: note: uninitialized use occurs here if (map && !is_kprobe) { ^~~ util/probe-event.c:2075:4: note: remove the 'if' if its condition is always false if (kernel_get_symbol_address_by_name(tp->symbol, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ util/probe-event.c:2064:17: note: initialize the variable 'map' to silence this warning struct map *map; ^ = NULL Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-m3501el55i10hctfbmi2qxzr@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/probe-event.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 2c1bca240597..35f5b7b7715c 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -2061,7 +2061,7 @@ static int find_perf_probe_point_from_map(struct probe_trace_point *tp, bool is_kprobe) { struct symbol *sym = NULL; - struct map *map; + struct map *map = NULL; u64 addr = tp->address; int ret = -ENOENT; -- 2.20.1