From: Su Yue <suy.fnst@cn.fujitsu.com>
Date: Tue, 6 Jun 2017 09:57:03 +0000 (+0800)
Subject: btrfs: Verify dir_item in replay_xattr_deletes
X-Git-Tag: v4.13-rc1~150^2~22
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=8ee8c2d62d5f9e7d1e592426d3d0b941df29f688;p=karo-tx-linux.git

btrfs: Verify dir_item in replay_xattr_deletes

replay_xattr_deletes calls btrfs_search_slot to get buffer and reads
name.

Call verify_dir_item to check name_len in replay_xattr_deletes to avoid
reading out of boundary.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 11cf38fb3a49..06c7ceb07282 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -2111,6 +2111,7 @@ static int replay_xattr_deletes(struct btrfs_trans_handle *trans,
 			      struct btrfs_path *path,
 			      const u64 ino)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_key search_key;
 	struct btrfs_path *log_path;
 	int i;
@@ -2152,6 +2153,12 @@ process_leaf:
 			u32 this_len = sizeof(*di) + name_len + data_len;
 			char *name;
 
+			ret = verify_dir_item(fs_info, path->nodes[0],
+					      path->slots[0], di);
+			if (ret) {
+				ret = -EIO;
+				goto out;
+			}
 			name = kmalloc(name_len, GFP_NOFS);
 			if (!name) {
 				ret = -ENOMEM;