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| author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2018-05-04 18:58:09 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2018-05-07 23:26:36 +0200 |
| commit | d3349b6b3c373ac1fbfb040b810fcee5e2adc7e0 (patch) | |
| tree | 3ff87e2bc973c2f5983886c404ecc41893c768b9 /drivers/block | |
| parent | block: Shorten interrupt disabled regions (diff) | |
| download | linux-d3349b6b3c373ac1fbfb040b810fcee5e2adc7e0.tar.xz linux-d3349b6b3c373ac1fbfb040b810fcee5e2adc7e0.zip | |
loop: remember whether sysfs_create_group() was done
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>
Diffstat (limited to 'drivers/block')
| -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 5d4e31655d96..5f0df2efc26c 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -809,16 +809,17 @@ 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 b78de9879f4f..4d42c7af7de7 100644 --- a/drivers/block/loop.h +++ b/drivers/block/loop.h @@ -58,6 +58,7 @@ 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; |