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Message-ID: <tencent_724B611BCF250EBAF7BBE333DF9E271BB208@qq.com>
From: Edward Adam Davis <eadavis@qq.com>
To: syzbot+4366624c0b5aac4906cf@syzkaller.appspotmail.com
Cc: bfoster@redhat.com,
	kent.overstreet@linux.dev,
	linux-bcachefs@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	syzkaller-bugs@googlegroups.com
Subject: [PATCH] bcachefs: bch2_fs_read_write_early needs to hold write lock
Date: Sat, 15 Jun 2024 19:44:04 +0800
In-Reply-To: <00000000000053e574061ad89521@google.com>
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bch2_fs_read_write_early() needs to hold state_lock to pretect and sync data.

Reported-by: syzbot+4366624c0b5aac4906cf@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
---
 fs/bcachefs/snapshot.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/bcachefs/snapshot.c b/fs/bcachefs/snapshot.c
index 51918acfd726..b27a4327274d 100644
--- a/fs/bcachefs/snapshot.c
+++ b/fs/bcachefs/snapshot.c
@@ -1566,7 +1566,9 @@ int bch2_delete_dead_snapshots(struct bch_fs *c)
 		return 0;
 
 	if (!test_bit(BCH_FS_started, &c->flags)) {
+		down_write(&c->state_lock);
 		ret = bch2_fs_read_write_early(c);
+		up_write(&c->state_lock);
 		bch_err_msg(c, ret, "deleting dead snapshots: error going rw");
 		if (ret)
 			return ret;
-- 
2.43.0