diff options
| author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2018-05-04 10:58:09 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-07-17 11:31:46 +0200 |
| commit | 43991e916eb9eac9ea0ef0317f9bfd3c491972cb (patch) | |
| tree | ca5ecf5795dc8d0a3a3578c20e2bfa919b1b16dc | |
| parent | 28db2b23f44c4a15e431327e488fc0680c4aceb0 (diff) | |
loop: remember whether sysfs_create_group() was done
commit d3349b6b3c373ac1fbfb040b810fcee5e2adc7e0 upstream.
syzbot is hitting WARN() triggered by memory allocation fault
injection [1] because loop module is calling sysfs_remove_group()
when sysfs_create_group() failed.
Fix this by remembering whether sysfs_create_group() succeeded.
[1] https://syzkaller.appspot.com/bug?id=3f86c0edf75c86d2633aeb9dd69eccc70bc7e90b
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+9f03168400f56df89dbc6f1751f4458fe739ff29@syzkaller.appspotmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Renamed sysfs_ready -> sysfs_inited.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/block/loop.c | 11 | ||||
| -rw-r--r-- | drivers/block/loop.h | 1 |
2 files changed, 7 insertions, 5 deletions
diff --git a/drivers/block/loop.c b/drivers/block/loop.c index aaa7000a4342..da3902ac16c8 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -835,16 +835,17 @@ static struct attribute_group loop_attribute_group = { .attrs= loop_attrs, }; -static int loop_sysfs_init(struct loop_device *lo) +static void loop_sysfs_init(struct loop_device *lo) { - return sysfs_create_group(&disk_to_dev(lo->lo_disk)->kobj, - &loop_attribute_group); + lo->sysfs_inited = !sysfs_create_group(&disk_to_dev(lo->lo_disk)->kobj, + &loop_attribute_group); } static void loop_sysfs_exit(struct loop_device *lo) { - sysfs_remove_group(&disk_to_dev(lo->lo_disk)->kobj, - &loop_attribute_group); + if (lo->sysfs_inited) + sysfs_remove_group(&disk_to_dev(lo->lo_disk)->kobj, + &loop_attribute_group); } static void loop_config_discard(struct loop_device *lo) diff --git a/drivers/block/loop.h b/drivers/block/loop.h index fb2237c73e61..60f0fd2c0c65 100644 --- a/drivers/block/loop.h +++ b/drivers/block/loop.h @@ -59,6 +59,7 @@ struct loop_device { struct kthread_worker worker; struct task_struct *worker_task; bool use_dio; + bool sysfs_inited; struct request_queue *lo_queue; struct blk_mq_tag_set tag_set; |