diff --git a/fs/qnx4/inode.c b/fs/qnx4/inode.c
index 4deb0eeadbde..42fcd500fad2 100644
--- a/fs/qnx4/inode.c
+++ b/fs/qnx4/inode.c
@@ -202,7 +202,8 @@ static int qnx4_fill_super(struct super_block *s, struct fs_context *fc)
 		return -ENOMEM;
 	s->s_fs_info = qs;
 
-	sb_set_blocksize(s, QNX4_BLOCK_SIZE);
+	if (!sb_set_blocksize(s, QNX4_BLOCK_SIZE))
+		return -EINVAL;
 
 	s->s_op = &qnx4_sops;
 	s->s_magic = QNX4_SUPER_MAGIC;