fuse: fix oops in revalidate when called with NULL nameidata
Some cases (e.g. ecryptfs) can call ->dentry_revalidate with NULL
nameidata.
https://bugzilla.kernel.org/show_bug.cgi?id=34732
Tyler Hicks pointed out that this bug was introduced by commit
e7c0a16786 "fuse: make fuse_dentry_revalidate() RCU aware"
Reported-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index c6ba49b..b32eb29 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -174,7 +174,7 @@
if (!inode)
return 0;
- if (nd->flags & LOOKUP_RCU)
+ if (nd && (nd->flags & LOOKUP_RCU))
return -ECHILD;
fc = get_fuse_conn(inode);