6.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ian Rogers <irogers@xxxxxxxxxx> [ Upstream commit 3536c2575e88a890cf696b4ccd3da36bc937853b ] Freeing the thread on failure won't work with reference count checking, use thread__delete(). Don't allocate the comm_str, use a stack allocation instead. Fixes: f6005cafebab72f8 ("perf thread: Add reference count checking") Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx> Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: James Clark <james.clark@xxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> Cc: Leo Yan <leo.yan@xxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20240508035301.1554434-5-irogers@xxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/perf/util/thread.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index 1aa8962dcf52c..515726489e36a 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -39,12 +39,13 @@ int thread__init_maps(struct thread *thread, struct machine *machine) struct thread *thread__new(pid_t pid, pid_t tid) { - char *comm_str; - struct comm *comm; RC_STRUCT(thread) *_thread = zalloc(sizeof(*_thread)); struct thread *thread; if (ADD_RC_CHK(thread, _thread) != NULL) { + struct comm *comm; + char comm_str[32]; + thread__set_pid(thread, pid); thread__set_tid(thread, tid); thread__set_ppid(thread, -1); @@ -56,13 +57,8 @@ struct thread *thread__new(pid_t pid, pid_t tid) init_rwsem(thread__namespaces_lock(thread)); init_rwsem(thread__comm_lock(thread)); - comm_str = malloc(32); - if (!comm_str) - goto err_thread; - - snprintf(comm_str, 32, ":%d", tid); + snprintf(comm_str, sizeof(comm_str), ":%d", tid); comm = comm__new(comm_str, 0, false); - free(comm_str); if (!comm) goto err_thread; @@ -76,7 +72,7 @@ struct thread *thread__new(pid_t pid, pid_t tid) return thread; err_thread: - free(thread); + thread__delete(thread); return NULL; } -- 2.43.0