From: Theodore Ts'o Date: Thu, 6 Jun 2013 15:14:31 +0000 (-0400) Subject: ext4: verify group number in verify_group_input() before using it X-Git-Tag: accepted/tizen/common/20141203.182822~1813^2~44 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b302ef2d3c73d8a07ed2f0679ce35f00b6dcacef;p=platform%2Fkernel%2Flinux-arm64.git ext4: verify group number in verify_group_input() before using it Check the group number for sanity earilier, before calling routines such as ext4_bg_has_super() or ext4_group_overhead_blocks(). Reported-by: Jonathan Salwan Signed-off-by: "Theodore Ts'o" --- diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index b27c96d..6ed4df2 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -79,12 +79,20 @@ static int verify_group_input(struct super_block *sb, ext4_fsblk_t end = start + input->blocks_count; ext4_group_t group = input->group; ext4_fsblk_t itend = input->inode_table + sbi->s_itb_per_group; - unsigned overhead = ext4_group_overhead_blocks(sb, group); - ext4_fsblk_t metaend = start + overhead; + unsigned overhead; + ext4_fsblk_t metaend; struct buffer_head *bh = NULL; ext4_grpblk_t free_blocks_count, offset; int err = -EINVAL; + if (group != sbi->s_groups_count) { + ext4_warning(sb, "Cannot add at group %u (only %u groups)", + input->group, sbi->s_groups_count); + return -EINVAL; + } + + overhead = ext4_group_overhead_blocks(sb, group); + metaend = start + overhead; input->free_blocks_count = free_blocks_count = input->blocks_count - 2 - overhead - sbi->s_itb_per_group; @@ -96,10 +104,7 @@ static int verify_group_input(struct super_block *sb, free_blocks_count, input->reserved_blocks); ext4_get_group_no_and_offset(sb, start, NULL, &offset); - if (group != sbi->s_groups_count) - ext4_warning(sb, "Cannot add at group %u (only %u groups)", - input->group, sbi->s_groups_count); - else if (offset != 0) + if (offset != 0) ext4_warning(sb, "Last group not full"); else if (input->reserved_blocks > input->blocks_count / 5) ext4_warning(sb, "Reserved blocks too high (%u)",