Re: [syzbot] [block?] general protection fault in blk_mq_free_tags_callback

[Hillf Danton]

> Date: Mon, 22 Sep 2025 13:24:25 -0700	[thread overview]
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    846bd2225ec3 Add linux-next specific files for 20250919
> git tree:       linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=13c238e2580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=135377594f35b576
> dashboard link: https://syzkaller.appspot.com/bug?extid=5c5d41e80248d610221f
> compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=155e427c580000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17bb8142580000

#syz test linux-next  master

--- x/block/blk-mq-tag.c
+++ y/block/blk-mq-tag.c
@@ -565,6 +565,7 @@ struct blk_mq_tags *blk_mq_init_tags(uns
 	if (!tags)
 		return NULL;
 
+	INIT_LIST_HEAD(&tags->page_list);
 	tags->nr_tags = total_tags;
 	tags->nr_reserved_tags = reserved_tags;
 	spin_lock_init(&tags->lock);
--