From: Ian Rogers irogers@google.com
[ Upstream commit 4584f084aa9d8033d5911935837dbee7b082d0e9 ]
An error may be in place when tracepoint_error is called, use parse_events__handle_error to avoid a memory leak and to capture the first and last error. Error detected by LLVM's libFuzzer using the following event:
$ perf stat -e 'msr/event/,f:e' event syntax error: 'msr/event/,f:e' ___ can't access trace events
Error: No permissions to read /sys/kernel/debug/tracing/events/f/e Hint: Try 'sudo mount -o remount,mode=755 /sys/kernel/debug/tracing/'
Initial error: event syntax error: 'msr/event/,f:e' ___ no value assigned for term Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
Signed-off-by: Ian Rogers irogers@google.com Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Andi Kleen ak@linux.intel.com Cc: Jin Yao yao.jin@linux.intel.com Cc: Jiri Olsa jolsa@redhat.com Cc: Mark Rutland mark.rutland@arm.com Cc: Namhyung Kim namhyung@kernel.org Cc: Peter Zijlstra peterz@infradead.org Cc: Stephane Eranian eranian@google.com Cc: clang-built-linux@googlegroups.com Link: http://lore.kernel.org/lkml/20191120180925.21787-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/util/parse-events.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index 6193be6d7639d..cfb64369a18d1 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -440,6 +440,7 @@ int parse_events_add_cache(struct list_head *list, int *idx, static void tracepoint_error(struct parse_events_error *e, int err, const char *sys, const char *name) { + const char *str; char help[BUFSIZ];
if (!e) @@ -453,18 +454,18 @@ static void tracepoint_error(struct parse_events_error *e, int err,
switch (err) { case EACCES: - e->str = strdup("can't access trace events"); + str = "can't access trace events"; break; case ENOENT: - e->str = strdup("unknown tracepoint"); + str = "unknown tracepoint"; break; default: - e->str = strdup("failed to add tracepoint"); + str = "failed to add tracepoint"; break; }
tracing_path__strerror_open_tp(err, help, sizeof(help), sys, name); - e->help = strdup(help); + parse_events__handle_error(e, 0, strdup(str), strdup(help)); }
static int add_tracepoint(struct list_head *list, int *idx,