[2/4] resize2fs: fix -M size calculations to avoid cutting off the inode table

Message ID 1380599974-2886-2-git-send-email-tytso@mit.edu
State Accepted, archived
Headers show

Commit Message

Theodore Y. Ts'o Oct. 1, 2013, 3:59 a.m.
If the file system's inode table blocks in the last block group are
located in the middle or the end of the block group, it's possible for
resize2fs -M to use a size which will require relocating the inode
table blocks in the last block group.  This can lead to all sorts of
problems, so solve it by simply guaranteeing that we will never do

Reported-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
 resize/resize2fs.c | 9 +++++++++
 1 file changed, 9 insertions(+)


diff --git a/resize/resize2fs.c b/resize/resize2fs.c
index 51b85b8..1e4ac19 100644
--- a/resize/resize2fs.c
+++ b/resize/resize2fs.c
@@ -2224,6 +2224,15 @@  blk64_t calculate_minimum_resize_size(ext2_filsys fs, int flags)
 	blks_needed = (groups-1) * EXT2_BLOCKS_PER_GROUP(fs->super);
 	blks_needed += overhead;
+	/*
+	 * Make sure blks_needed covers the end of the inode table in
+	 * the last block group.
+	 */
+	overhead = ext2fs_inode_table_loc(fs, groups-1) +
+		fs->inode_blocks_per_group;
+	if (blks_needed < overhead)
+		blks_needed = overhead;
 	if (flags & RESIZE_DEBUG_MIN_CALC)
 		printf("Estimated blocks needed: %llu\n", blks_needed);