Re: [syzbot] [kernfs?] possible deadlock in kernfs_seq_start

[Hillf Danton]

On Tue, 07 May 2024 22:36:18 -0700
> syzbot has found a reproducer for the following issue on:
> 
> HEAD commit:    dccb07f2914c Merge tag 'for-6.9-rc7-tag' of git://git.kern..
> git tree:       upstream
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1367a504980000

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git  dccb07f2914c

--- x/fs/namei.c
+++ y/fs/namei.c
@@ -3494,6 +3494,7 @@ static struct dentry *lookup_open(struct
 			goto out_dput;
 		}
 
+		BUG_ON(!got_write);
 		error = dir_inode->i_op->create(idmap, dir_inode, dentry,
 						mode, open_flag & O_EXCL);
 		if (error)
--