2010-01-05 20:33:56

by Johannes Hirte

[permalink] [raw]
Subject: [PATCH] check for NULL pointer dereference in btrfs_set_acl

Check for for NULL pointer in btrfs_set_acl and omit calling
posix_acl_equiv_mode in this case to avoid NULL pointer dereference there.

Signed-off-by: Johannes Hirte <[email protected]>

diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c
index 2e9e699..3a3a96d 100644
--- a/fs/btrfs/acl.c
+++ b/fs/btrfs/acl.c
@@ -111,13 +111,15 @@ static int btrfs_set_acl(struct btrfs_trans_handle
*trans,

switch (type) {
case ACL_TYPE_ACCESS:
- mode = inode->i_mode;
- ret = posix_acl_equiv_mode(acl, &mode);
- if (ret < 0)
- return ret;
- ret = 0;
- inode->i_mode = mode;
name = POSIX_ACL_XATTR_ACCESS;
+ if (acl) {
+ mode = inode->i_mode;
+ ret = posix_acl_equiv_mode(acl, &mode);
+ if (ret < 0)
+ return ret;
+ ret = 0;
+ inode->i_mode = mode;
+ }
break;
case ACL_TYPE_DEFAULT:
if (!S_ISDIR(inode->i_mode))