From: Masatake YAMATO <yamato@redhat.com>
Date: Wed, 28 May 2008 05:45:10 +0000 (+0900)
Subject: dlm: check for null in device_write
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=254ae43ab8d7877c980fca3636624e0777a70fa4;p=openwrt%2Fstaging%2Fblogic.git

dlm: check for null in device_write

If `device_write' method is called via "dlm-control",
file->private_data is NULL. (See ctl_device_open() in
user.c. ) Through proc->flags is read.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
---

diff --git a/fs/dlm/user.c b/fs/dlm/user.c
index ebbcf38fd33b..1aa76b32d056 100644
--- a/fs/dlm/user.c
+++ b/fs/dlm/user.c
@@ -538,7 +538,7 @@ static ssize_t device_write(struct file *file, const char __user *buf,
 
 	/* do we really need this? can a write happen after a close? */
 	if ((kbuf->cmd == DLM_USER_LOCK || kbuf->cmd == DLM_USER_UNLOCK) &&
-	    test_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags))
+	    (proc && test_bit(DLM_PROC_FLAGS_CLOSING, &proc->flags)))
 		return -EINVAL;
 
 	sigfillset(&allsigs);