From: Erez Zadok <ezk@cs.sunysb.edu>
Date: Fri, 10 Dec 2010 03:05:31 +0000 (-0500)
Subject: Unionfs: don't dereference null pointers if dir="" was given
X-Git-Tag: master_bottom
X-Git-Url: https://git.fsl.cs.sunysb.edu/?a=commitdiff_plain;h=a8b896c6d81bc7b8abf4a75fe4a36138f17d21d5;p=unionfs-2.6.23.y.git

Unionfs: don't dereference null pointers if dir="" was given

Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
---

diff --git a/fs/unionfs/main.c b/fs/unionfs/main.c
index 875c56f1840..c48c942fcf8 100644
--- a/fs/unionfs/main.c
+++ b/fs/unionfs/main.c
@@ -288,7 +288,7 @@ static int parse_dirs_option(struct super_block *sb, struct unionfs_dentry_info
 	if (options[0] == '\0') {
 		printk(KERN_ERR "unionfs: no branches specified\n");
 		err = -EINVAL;
-		goto out;
+		goto out_return;
 	}
 
 	/*
@@ -304,14 +304,17 @@ static int parse_dirs_option(struct super_block *sb, struct unionfs_dentry_info
 		kcalloc(branches, sizeof(struct unionfs_data), GFP_KERNEL);
 	if (unlikely(!UNIONFS_SB(sb)->data)) {
 		err = -ENOMEM;
-		goto out;
+		goto out_return;
 	}
 
 	lower_root_info->lower_paths =
 		kcalloc(branches, sizeof(struct path), GFP_KERNEL);
 	if (unlikely(!lower_root_info->lower_paths)) {
 		err = -ENOMEM;
-		goto out;
+		/* free the underlying pointer array */
+		kfree(UNIONFS_SB(sb)->data);
+		UNIONFS_SB(sb)->data = NULL;
+		goto out_return;
 	}
 
 	/* now parsing a string such as "b1:b2=rw:b3=ro:b4" */
@@ -432,6 +435,7 @@ out:
 		lower_root_info->lower_paths = NULL;
 		UNIONFS_SB(sb)->data = NULL;
 	}
+out_return:
 	return err;
 }