When gfs2_fill_super() fails, destroy_workqueue() is called within gfs2_gl_hash_clear(), and the subsequent code path calls destroy_workqueue() on the same work queue again.
This issue can be fixed by setting the work queue pointer to NULL after the first destroy_workqueue() call and checking for a NULL pointer before attempting to destroy the work queue again.
Reported-by: syzbot+d34c2a269ed512c531b0@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=d34c2a269ed512c531b0 Fixes: 30e388d57367 ("gfs2: Switch to a per-filesystem glock workqueue") Cc: stable@vger.kernel.org Signed-off-by: Julian Sun sunjunchao2870@gmail.com --- fs/gfs2/glock.c | 1 + fs/gfs2/ops_fstype.c | 3 ++- 2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index 32991cb22023..5838039d78e3 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -2273,6 +2273,7 @@ void gfs2_gl_hash_clear(struct gfs2_sbd *sdp) gfs2_free_dead_glocks(sdp); glock_hash_walk(dump_glock_func, sdp); destroy_workqueue(sdp->sd_glock_wq); + sdp->sd_glock_wq = NULL; }
static const char *state2str(unsigned state) diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c index 0561edd6cc86..5c0e1b24d6ec 100644 --- a/fs/gfs2/ops_fstype.c +++ b/fs/gfs2/ops_fstype.c @@ -1308,7 +1308,8 @@ static int gfs2_fill_super(struct super_block *sb, struct fs_context *fc) fail_delete_wq: destroy_workqueue(sdp->sd_delete_wq); fail_glock_wq: - destroy_workqueue(sdp->sd_glock_wq); + if (sdp->sd_glock_wq) + destroy_workqueue(sdp->sd_glock_wq); fail_free: free_sbd(sdp); sb->s_fs_info = NULL;