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 11:37:54 +0200 |
| commit | b2660f35d3da4d960b935c9b683b92511d4d54b4 (patch) | |
| tree | 0a1df8cfda9cd9a1d14eb19190b49ebf93f9dac4 | |
| parent | 684db31e7471c39aad887820ff62804dac60b444 (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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Renamed sysfs_ready -> sysfs_inited.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -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 29c847137e42..9f840d9fdfcb 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -824,16 +824,17 @@ 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; |