Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6

[sfrench/cifs-2.6.git] / fs / open.c

diff --git a/fs/open.c b/fs/open.c
index 54198538b67e7a285fadcc4a8eb905cfe32f4864..a4b12022edaa27cb8cd3ea865d14f1368d507660 100644 (file)
--- a/fs/open.c
+++ b/fs/open.c
@@ -903,6 +903,18 @@ struct file *dentry_open(struct dentry *dentry, struct vfsmount *mnt, int flags)
        int error;
        struct file *f;
 
+       /*
+        * We must always pass in a valid mount pointer.   Historically
+        * callers got away with not passing it, but we must enforce this at
+        * the earliest possible point now to avoid strange problems deep in the
+        * filesystem stack.
+        */
+       if (!mnt) {
+               printk(KERN_WARNING "%s called with NULL vfsmount\n", __func__);
+               dump_stack();
+               return ERR_PTR(-EINVAL);
+       }
+
        error = -ENFILE;
        f = get_empty_filp();
        if (f == NULL) {