From: Miklos Szeredi <mszeredi@suse.cz>
Date: Tue, 10 May 2011 15:35:58 +0000 (+0200)
Subject: fuse: fix oops in revalidate when called with NULL nameidata
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d24339059d640f108c08ba99ef30e3bafa10f8e4;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

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 c6ba49bd95b3..b32eb29a4e6f 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -174,7 +174,7 @@ static int fuse_dentry_revalidate(struct dentry *entry, struct nameidata *nd)
 		if (!inode)
 			return 0;
 
-		if (nd->flags & LOOKUP_RCU)
+		if (nd && (nd->flags & LOOKUP_RCU))
 			return -ECHILD;
 
 		fc = get_fuse_conn(inode);