Make e2fsck check the superblock's inode_size to make sure it is

sane before we start depending on it!

diff --git a/e2fsck/ChangeLog b/e2fsck/ChangeLog
index 7a0d705..cbbe2fe 100644 (file)
--- a/e2fsck/ChangeLog
+++ b/e2fsck/ChangeLog
@@ -1,5 +1,8 @@
 2005-03-20  Theodore Ts'o  <tytso@mit.edu>
 
+       * super.c (check_super_block): Add sanity checks for the
+               superblock's inode_size field.
+
        * pass3.c (check_root, e2fsck_get_lost_and_found): Call
                ext2fs_write_new_inode() instead of ext2fs_write_inode().
 

diff --git a/e2fsck/super.c b/e2fsck/super.c
index 7e19e8e..294cd80 100644 (file)
--- a/e2fsck/super.c
+++ b/e2fsck/super.c
@@ -446,6 +446,7 @@ void check_super_block(e2fsck_t ctx)
        blk_t   bpg_max;
        int     inodes_per_block;
        int     ipg_max;
+       int     inode_size;
        dgrp_t  i;
        blk_t   should_be;
        struct problem_context  pctx;
@@ -494,7 +495,18 @@ void check_super_block(e2fsck_t ctx)
        check_super_value(ctx, "reserved_gdt_blocks", 
                          sb->s_reserved_gdt_blocks, MAX_CHECK, 0,
                          fs->blocksize/4);
-
+       inode_size = EXT2_INODE_SIZE(sb);
+       check_super_value(ctx, "inode_size",
+                         inode_size, MIN_CHECK | MAX_CHECK,
+                         EXT2_GOOD_OLD_INODE_SIZE, fs->blocksize);
+       if (inode_size & (inode_size - 1)) {
+               pctx.num = inode_size;
+               pctx.str = "inode_size";
+               fix_problem(ctx, PR_0_MISC_CORRUPT_SUPER, &pctx);
+               ctx->flags |= E2F_FLAG_ABORT; /* never get here! */
+               return;
+       }
+               
        if (!ctx->num_blocks) {
                pctx.errcode = e2fsck_get_device_size(ctx);
                if (pctx.errcode && pctx.errcode != EXT2_ET_UNIMPLEMENTED) {