Handle a failed read of the inotify event before comparing its signed ssize_t result with sizeof(struct inotify_event). This avoids treating -1 as a large unsigned length and inspecting the uninitialized event buffer.
Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Sahaj Chaudhari <[email protected]> --- tools/testing/selftests/cgroup/test_pids_local_events.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/cgroup/test_pids_local_events.c b/tools/testing/selftests/cgroup/test_pids_local_events.c index fa501e209187..59885901fbf5 100644 --- a/tools/testing/selftests/cgroup/test_pids_local_events.c +++ b/tools/testing/selftests/cgroup/test_pids_local_events.c @@ -90,7 +90,11 @@ static int test_pids_events_notify(const char *root) goto cleanup; } n = read(inotify_fd, event_buf.bytes, sizeof(event_buf.bytes)); - if (n < sizeof(struct inotify_event) || + if (n < 0) { + reason = "failed to read pids.events notification"; + goto cleanup; + } + if ((size_t)n < sizeof(struct inotify_event) || !(event_buf.align.mask & IN_MODIFY)) { reason = "received no pids.events modify notification"; goto cleanup; -- 2.43.0
