Re: [syzbot] [f2fs?] KASAN: slab-use-after-free Read in kill_f2fs_super

[Hillf Danton]

On Fri, 12 Jan 2024 10:14:27 -0800
> syzbot has found a reproducer for the following issue on:
> 
> HEAD commit:    70d201a40823 Merge tag 'f2fs-for-6.8-rc1' of git://git.ker..
> git tree:       upstream
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=16b910ede80000

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

--- x/fs/f2fs/super.c
+++ y/fs/f2fs/super.c
@@ -4880,6 +4880,7 @@ free_sbi:
 	if (sbi->s_chksum_driver)
 		crypto_free_shash(sbi->s_chksum_driver);
 	kfree(sbi);
+	sb->s_fs_info = NULL;
 
 	/* give only one another chance */
 	if (retry_cnt > 0 && skip_recovery) {
--