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>
Acked-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 3f9b45704fcdfb83eeda6a55740c56de7a048ce5..a649305b205968e024a967555520581c00f3356e 100644 (file)
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -126,7 +126,7 @@ 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;
 
@@ -141,6 +141,7 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
        if (!options)
                return -ENOMEM;
 
+       orig = options;
 
        while ((p = strsep(&options, ",")) != NULL) {
                int token;
@@ -273,7 +274,7 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
                }
        }
 out:
-       kfree(options);
+       kfree(orig);
        return ret;
 }