From: Theodore Ts'o <tytso@mit.edu>
Date: Mon, 20 Jul 2009 02:43:33 +0000 (-0400)
Subject: libext2fs: Fix regression in ext2fs_extent_set_bmap()
X-Git-Tag: v1.41.9~32
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=16e470e65010ba3f0516cf9cdf1bd6c98f064e3f;p=thirdparty%2Fe2fsprogs.git

libext2fs: Fix regression in ext2fs_extent_set_bmap()

Commit 0dc291611 introduced a regression when unmapping the first
block in an extent.  This caused e2fsck -fD to corrupt large
directories if the directory has to shrink by more than one block.
The problem was set_bmap should only go to a next leaf when setting a
first block in an extent, and not when it is unmapping the first block
in an extent.

Addresses-Debian-Bug: #537510

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
---

diff --git a/lib/ext2fs/extent.c b/lib/ext2fs/extent.c
index 7fcc2cf9c..9d7b7de7d 100644
--- a/lib/ext2fs/extent.c
+++ b/lib/ext2fs/extent.c
@@ -1296,11 +1296,12 @@ errcode_t ext2fs_extent_set_bmap(ext2_extent_handle_t handle,
 			}
 			if (retval)
 				goto done;
+			retval = ext2fs_extent_get(handle,
+						   EXT2_EXTENT_NEXT_LEAF,
+						   &extent);
+			if (retval)
+				goto done;
 		}
-		retval = ext2fs_extent_get(handle, EXT2_EXTENT_NEXT_LEAF,
-					   &extent);
-		if (retval)
-			goto done;
 		extent.e_pblk++;
 		extent.e_lblk++;
 		extent.e_len--;