diff options
| author | Dmitry Antipov <dmantipov@yandex.ru> | 2025-06-06 14:22:42 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-06-19 15:32:36 +0200 |
| commit | e09c0600beea469b3ebf974464e526a02d59ad62 (patch) | |
| tree | c46e96c9a7309de4e341afc60af33431af76d865 | |
| parent | b8df8cb8f7eef52baa9ac5bf36a405ca67945a91 (diff) | |
ring-buffer: Fix buffer locking in ring_buffer_subbuf_order_set()
commit 40ee2afafc1d9fe3aa44a6fbe440d78a5c96a72e upstream.
Enlarge the critical section in ring_buffer_subbuf_order_set() to
ensure that error handling takes place with per-buffer mutex held,
thus preventing list corruption and other concurrency-related issues.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
Link: https://lore.kernel.org/20250606112242.1510605-1-dmantipov@yandex.ru
Reported-by: syzbot+05d673e83ec640f0ced9@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=05d673e83ec640f0ced9
Fixes: f9b94daa542a8 ("ring-buffer: Set new size of the ring buffer sub page")
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | kernel/trace/ring_buffer.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 154d4d78acb5..e95e96cd29d3 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -6754,7 +6754,7 @@ int ring_buffer_subbuf_order_set(struct trace_buffer *buffer, int order) old_size = buffer->subbuf_size; /* prevent another thread from changing buffer sizes */ - mutex_lock(&buffer->mutex); + guard(mutex)(&buffer->mutex); atomic_inc(&buffer->record_disabled); /* Make sure all commits have finished */ @@ -6859,7 +6859,6 @@ int ring_buffer_subbuf_order_set(struct trace_buffer *buffer, int order) } atomic_dec(&buffer->record_disabled); - mutex_unlock(&buffer->mutex); return 0; @@ -6868,7 +6867,6 @@ error: buffer->subbuf_size = old_size; atomic_dec(&buffer->record_disabled); - mutex_unlock(&buffer->mutex); for_each_buffer_cpu(buffer, cpu) { cpu_buffer = buffer->buffers[cpu]; |