From 52bb0b050ab7001f92f8110c0167cedec53bdcb5 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Sun, 6 Apr 2008 17:00:23 -0400 Subject: [PATCH] libext2fs: Fix resize inode creation with non-standard s_first_data_block Thanks to Max Lindner (lokimuh) for pointing this out. I'm playing around a bit with ext2 and multi-user encryption and I need space for my key management. So I set s_first_data_block to 4000 or something like that. This way mke2fs segfaults when executing ext2fs_create_resize_inode() because blk_t goal = 3 + sb->s_reserved_gdt_blocks + fs->desc_blocks + fs->inode_blocks_per_group; will produce a integer underrun later and segfault then in the ext2fs_test_bit assembler inline function. when exchanging 3 with 2 + sb->s_first_data_block, mke2fs does not segfault. I'm not 100% sure if thats the correct way dealing with this issue but I think its a proper solution. Addresses-Sourceforge-Bug: #1935847 Signed-off-by: "Theodore Ts'o" --- lib/ext2fs/res_gdt.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/lib/ext2fs/res_gdt.c b/lib/ext2fs/res_gdt.c index fa72fc9..ef87ab7 100644 --- a/lib/ext2fs/res_gdt.c +++ b/lib/ext2fs/res_gdt.c @@ -93,8 +93,9 @@ errcode_t ext2fs_create_resize_inode(ext2_filsys fs) if (retval) goto out_inode; } else { - blk_t goal = 3 + sb->s_reserved_gdt_blocks + - fs->desc_blocks + fs->inode_blocks_per_group; + blk_t goal = sb->s_first_data_block + fs->desc_blocks + + sb->s_reserved_gdt_blocks + 2 + + fs->inode_blocks_per_group; retval = ext2fs_alloc_block(fs, goal, 0, &dindir_blk); if (retval) -- 1.8.3.1