btrfsck: Exit and print error message when not able to open a device

If btrfsck is not able to open a device, it segfaults. This fixes it and
prints an error message too.

1 files changed, 3 insertions, 0 deletions

diff --git a/btrfsck.c b/btrfsck.c
index c50de7d8..1fcc372e 100644
--- a/btrfsck.c
+++ b/btrfsck.c
@@ -2075,6 +2075,9 @@ int main(int ac, char **av)
 	radix_tree_init();
 	root = open_ctree(av[1], 0, 0);
 
+	if (root == NULL)
+		return 1;
+
 	ret = check_extents(root);
 	if (ret)
 		goto out;