6.9-stable review patch. If anyone has any objections, please let me know.
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From: Ian Rogers irogers@google.com
[ 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@google.com Cc: Adrian Hunter adrian.hunter@intel.com Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Ingo Molnar mingo@redhat.com Cc: James Clark james.clark@arm.com Cc: Jiri Olsa jolsa@kernel.org Cc: Kan Liang kan.liang@linux.intel.com Cc: Leo Yan leo.yan@linux.dev Cc: Mark Rutland mark.rutland@arm.com Cc: Namhyung Kim namhyung@kernel.org Cc: Peter Zijlstra peterz@infradead.org Link: https://lore.kernel.org/r/20240508035301.1554434-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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; }