btrfs: fix missing snapshot drew unlock when root is dead during swap…

… activation When activating a swap file we acquire the root's snapshot drew lock and then check if the root is dead, failing and returning with -EPERM if it's dead but without unlocking the root's snapshot lock. Fix this by adding the missing unlock. Fixes: 60021bd ("btrfs: prevent subvol with swapfile from being deleted") Reviewed-by: Johannes Thumshirn <[email protected]> Reviewed-by: David Sterba <[email protected]> Reviewed-by: Qu Wenruo <[email protected]> Signed-off-by: Filipe Manana <[email protected]> Signed-off-by: David Sterba <[email protected]>
btrfs · Dec 2, 2024 · 1363dba · 1363dba
1 parent 161b3ec
commit 1363dba
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
@@ -9876,6 +9876,7 @@ static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
 	if (btrfs_root_dead(root)) {
 		spin_unlock(&root->root_item_lock);
 
+		btrfs_drew_write_unlock(&root->snapshot_lock);
 		btrfs_exclop_finish(fs_info);
 		btrfs_warn(fs_info,
 		"cannot activate swapfile because subvolume %llu is being deleted",