Btrfs: kfree correct pointer during mount option parsing

commit da495ecc0fb096b383754952a1c152147bc95b52 upstream.

We kstrdup the options string, but then strsep screws with the pointer,
so when we kfree() it, we're not giving it the right pointer.

Tested-by: Andy Lutomirski <luto@mit.edu>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 8a1ea6e64575a34c507c29cd8c84ec4944885583..f8b4521de90750c32cd2347baea5e25355748066 100644 (file)
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -128,7 +128,7 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
 {
        struct btrfs_fs_info *info = root->fs_info;
        substring_t args[MAX_OPT_ARGS];
-       char *p, *num;
+       char *p, *num, *orig;
        int intarg;
        int ret = 0;
 
@@ -143,6 +143,7 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
        if (!options)
                return -ENOMEM;
 
+       orig = options;
 
        while ((p = strsep(&options, ",")) != NULL) {
                int token;
@@ -280,7 +281,7 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
                }
        }
 out:
-       kfree(options);
+       kfree(orig);
        return ret;
 }