From: Leo Yan <leo.yan@xxxxxxxxxx> [ Upstream commit 111442cfc8abdeaa7ec1407f07ef7b3e5f76654e ] Based on the following report from Smatch, fix the potential NULL pointer dereference check. tools/perf/builtin-top.c:109 perf_top__parse_source() warn: variable dereferenced before check 'he' (see line 103) tools/perf/builtin-top.c:233 perf_top__show_details() warn: variable dereferenced before check 'he' (see line 228) tools/perf/builtin-top.c 101 static int perf_top__parse_source(struct perf_top *top, struct hist_entry *he) 102 { 103 struct perf_evsel *evsel = hists_to_evsel(he->hists); ^^^^ 104 struct symbol *sym; 105 struct annotation *notes; 106 struct map *map; 107 int err = -1; 108 109 if (!he || !he->ms.sym) 110 return -1; This patch moves the values assignment after validating pointer 'he'. Signed-off-by: Leo Yan <leo.yan@xxxxxxxxxx> Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx> Cc: Alexios Zavras <alexios.zavras@xxxxxxxxx> Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx> Cc: Changbin Du <changbin.du@xxxxxxxxx> Cc: David S. Miller <davem@xxxxxxxxxxxxx> Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx> Cc: Eric Saint-Etienne <eric.saint.etienne@xxxxxxxxxx> Cc: Jin Yao <yao.jin@xxxxxxxxxxxxxxx> Cc: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx> Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx> Cc: Song Liu <songliubraving@xxxxxx> Cc: Suzuki Poulouse <suzuki.poulose@xxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Thomas Richter <tmricht@xxxxxxxxxxxxx> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Link: http://lkml.kernel.org/r/20190702103420.27540-4-leo.yan@xxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/perf/builtin-top.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index fbbb0da43abb..42e3a4d07b18 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -101,7 +101,7 @@ static void perf_top__resize(struct perf_top *top) static int perf_top__parse_source(struct perf_top *top, struct hist_entry *he) { - struct perf_evsel *evsel = hists_to_evsel(he->hists); + struct perf_evsel *evsel; struct symbol *sym; struct annotation *notes; struct map *map; @@ -110,6 +110,8 @@ static int perf_top__parse_source(struct perf_top *top, struct hist_entry *he) if (!he || !he->ms.sym) return -1; + evsel = hists_to_evsel(he->hists); + sym = he->ms.sym; map = he->ms.map; @@ -226,7 +228,7 @@ static void perf_top__record_precise_ip(struct perf_top *top, static void perf_top__show_details(struct perf_top *top) { struct hist_entry *he = top->sym_filter_entry; - struct perf_evsel *evsel = hists_to_evsel(he->hists); + struct perf_evsel *evsel; struct annotation *notes; struct symbol *symbol; int more; @@ -234,6 +236,8 @@ static void perf_top__show_details(struct perf_top *top) if (!he) return; + evsel = hists_to_evsel(he->hists); + symbol = he->ms.sym; notes = symbol__annotation(symbol); -- 2.20.1