tune2fs: rewrite metadata checksums when resizing inode size

When we use tune2fs -I new_ino_size to change inode size, if
everything is OK, the corresponding ext4_group_desc.bg_free_blocks_count
will be decreased, so obviously, we need to re-compute the group
descriptor checksums, and the inode 's size has also changed, we also
need to recompute the checksums of inodes for metadata_csum
filesystem, so here we choose to call a rewrite_metadata_checksums(),
this will fix checksum issues.

Meanwhile, the patch will trigger an existing memory write overflow,
which will casue segfault, please see the next patch.

Signed-off-by: Xiaoguang Wang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/misc/tune2fs.c b/misc/tune2fs.c
index 065b483..91dc7c1 100644 (file)
--- a/misc/tune2fs.c
+++ b/misc/tune2fs.c
@@ -2908,8 +2908,7 @@ retry_open:
                                EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
                        rewrite_checksums = 1;
        }
-       if (rewrite_checksums)
-               rewrite_metadata_checksums(fs);
+
        if (I_flag) {
                if (mount_flags & EXT2_MF_MOUNTED) {
                        fputs(_("The inode size may only be "
@@ -2935,6 +2934,7 @@ retry_open:
                if (resize_inode(fs, new_inode_size) == 0) {
                        printf(_("Setting inode size %lu\n"),
                                                        new_inode_size);
+                       rewrite_checksums = 1;
                } else {
                        printf("%s", _("Failed to change inode size\n"));
                        rc = 1;
@@ -2942,6 +2942,9 @@ retry_open:
                }
        }
 
+       if (rewrite_checksums)
+               rewrite_metadata_checksums(fs);
+
        if (l_flag)
                list_super(sb);
        if (stride_set) {