[patch 1/3] NFS: fix potential NULL pointer dereference

[Cyrill Gorcunov <gorcunov@gmail.com>]

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It's possible to get NULL pointer dereference
if kstrndup failed

Here is a possible scenario

nfs4_get_sb
  nfs4_validate_mount_data
    o kstrndup failed so args->nfs_server.export_path = NULL
  nfs4_create_server
    nfs4_path_walk(..., NULL) -> Oops!

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

---

Index: linux-2.6.git/fs/nfs/super.c
===================================================================
--- linux-2.6.git.orig/fs/nfs/super.c	2008-04-15 23:01:30.000000000 +0400
+++ linux-2.6.git/fs/nfs/super.c	2008-04-16 20:01:44.000000000 +0400
@@ -1858,6 +1858,8 @@ static int nfs4_validate_mount_data(void
 		if (len > NFS4_MAXPATHLEN)
 			return -ENAMETOOLONG;
 		args->nfs_server.export_path = kstrndup(c, len, GFP_KERNEL);
+		if (!args->nfs_server.export_path)
+			return -ENOMEM;
 
 		dprintk("NFS: MNTPATH: '%s'\n", args->nfs_server.export_path);

--