| Message ID | 20230202141956.2299521-1-gregkh@linuxfoundation.org (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | trace/blktrace: fix memory leak with using debugfs_lookup() | expand |
On 2/2/23 06:19, Greg Kroah-Hartman wrote: > When calling debugfs_lookup() the result must have dput() called on it, > otherwise the memory will leak over time. To make things simpler, just > call debugfs_lookup_and_remove() instead which handles all of the logic > at once. > > Cc: Jens Axboe <axboe@kernel.dk> > Cc: Steven Rostedt <rostedt@goodmis.org> > Cc: Masami Hiramatsu <mhiramat@kernel.org> > Cc: linux-block@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Cc: linux-trace-kernel@vger.kernel.org > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > --- > kernel/trace/blktrace.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c > index 918a7d12df8f..5743be559415 100644 > --- a/kernel/trace/blktrace.c > +++ b/kernel/trace/blktrace.c > @@ -320,8 +320,8 @@ static void blk_trace_free(struct request_queue *q, struct blk_trace *bt) > * under 'q->debugfs_dir', thus lookup and remove them. > */ > if (!bt->dir) { > - debugfs_remove(debugfs_lookup("dropped", q->debugfs_dir)); > - debugfs_remove(debugfs_lookup("msg", q->debugfs_dir)); > + debugfs_lookup_and_remove("dropped", q->debugfs_dir); > + debugfs_lookup_and_remove("msg", q->debugfs_dir); > } else { > debugfs_remove(bt->dir); > } Reviewed-by: Bart Van Assche <bvanassche@acm.org>
On Thu, 02 Feb 2023 15:19:56 +0100, Greg Kroah-Hartman wrote: > When calling debugfs_lookup() the result must have dput() called on it, > otherwise the memory will leak over time. To make things simpler, just > call debugfs_lookup_and_remove() instead which handles all of the logic > at once. > > Applied, thanks! [1/1] trace/blktrace: fix memory leak with using debugfs_lookup() commit: 83e8864fee26f63a7435e941b7c36a20fd6fe93e Best regards,
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 918a7d12df8f..5743be559415 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -320,8 +320,8 @@ static void blk_trace_free(struct request_queue *q, struct blk_trace *bt) * under 'q->debugfs_dir', thus lookup and remove them. */ if (!bt->dir) { - debugfs_remove(debugfs_lookup("dropped", q->debugfs_dir)); - debugfs_remove(debugfs_lookup("msg", q->debugfs_dir)); + debugfs_lookup_and_remove("dropped", q->debugfs_dir); + debugfs_lookup_and_remove("msg", q->debugfs_dir); } else { debugfs_remove(bt->dir); }
When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once. Cc: Jens Axboe <axboe@kernel.dk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: linux-block@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-kernel@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- kernel/trace/blktrace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)