From e5d395974e043cdcedcd84a0d41aaebb723786d8 Mon Sep 17 00:00:00 2001 From: Chengguang Xu Date: Tue, 23 Jul 2019 19:21:54 +0800 Subject: ext2: fix block range in ext2_data_block_valid() For block validity we should check the block range from start_block to start_block + count - 1, so fix the range in ext2_data_block_valid() and also modify the count argument properly in calling place. Signed-off-by: Chengguang Xu Link: https://lore.kernel.org/r/20190723112155.20329-1-cgxu519@zoho.com.cn Signed-off-by: Jan Kara --- fs/ext2/balloc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/ext2/balloc.c') diff --git a/fs/ext2/balloc.c b/fs/ext2/balloc.c index 547c165299c0..92e9a7489174 100644 --- a/fs/ext2/balloc.c +++ b/fs/ext2/balloc.c @@ -1203,13 +1203,13 @@ int ext2_data_block_valid(struct ext2_sb_info *sbi, ext2_fsblk_t start_blk, unsigned int count) { if ((start_blk <= le32_to_cpu(sbi->s_es->s_first_data_block)) || - (start_blk + count < start_blk) || - (start_blk > le32_to_cpu(sbi->s_es->s_blocks_count))) + (start_blk + count - 1 < start_blk) || + (start_blk + count - 1 >= le32_to_cpu(sbi->s_es->s_blocks_count))) return 0; /* Ensure we do not step over superblock */ if ((start_blk <= sbi->s_sb_block) && - (start_blk + count >= sbi->s_sb_block)) + (start_blk + count - 1 >= sbi->s_sb_block)) return 0; return 1; -- cgit v1.2.3