mainline inclusion
from mainline-v5.14-rc1
commit f0c1c4d2
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I597XM
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f0c1c4d2864ed614f90d2da1bab1a1c42907b940

--------------------------------

tagset can't be used after blk_cleanup_queue() is returned because
freeing tagset usually follows blk_clenup_queue(). Commit d97e594c
("blk-mq: Use request queue-wide tags for tagset-wide sbitmap") adds
check on q->tag_set->flags in blk_mq_exit_sched(), and causes
use-after-free.

Fixes it by using hctx->flags.

Reported-by: syzbot+77ba3d171a25c56756ea@syzkaller.appspotmail.com
Fixes: d97e594c ("blk-mq: Use request queue-wide tags for tagset-wide sbitmap")
Cc: John Garry <john.garry@huawei.com>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Tested-by: NJohn Garry <john.garry@huawei.com>
Reviewed-by: NJohn Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/20210609063046.122843-1-ming.lei@redhat.comSigned-off-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NYufen Yu <yuyufen@huawei.com>
Reviewed-by: NJason Yan <yanaijie@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>