fat: fix d_revalidate oopsen on NFS exports
can't blindly check nd->flags in ->d_revalidate()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index f88f752..adae3fb 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -43,7 +43,7 @@
static int vfat_revalidate(struct dentry *dentry, struct nameidata *nd)
{
- if (nd->flags & LOOKUP_RCU)
+ if (nd && nd->flags & LOOKUP_RCU)
return -ECHILD;
/* This is not negative dentry. Always valid. */
@@ -54,7 +54,7 @@
static int vfat_revalidate_ci(struct dentry *dentry, struct nameidata *nd)
{
- if (nd->flags & LOOKUP_RCU)
+ if (nd && nd->flags & LOOKUP_RCU)
return -ECHILD;
/*