From ae49eeec785025373e28dc24c8351c6bba688d99 Mon Sep 17 00:00:00 2001 From: Lukas Czerner Date: Thu, 11 Oct 2012 12:28:38 +0200 Subject: [PATCH] ext3: Avoid underflow of in ext3_trim_fs() Currently if len argument in ext3_trim_fs() is smaller than one block, the 'end' variable underflow. Avoid that by returning EINVAL if len is smaller than file system block. Also remove useless unlikely(). Signed-off-by: Lukas Czerner Signed-off-by: Jan Kara --- fs/ext3/balloc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/ext3/balloc.c b/fs/ext3/balloc.c index 7320a66e958f..22548f56197b 100644 --- a/fs/ext3/balloc.c +++ b/fs/ext3/balloc.c @@ -2101,8 +2101,9 @@ int ext3_trim_fs(struct super_block *sb, struct fstrim_range *range) end = start + (range->len >> sb->s_blocksize_bits) - 1; minlen = range->minlen >> sb->s_blocksize_bits; - if (unlikely(minlen > EXT3_BLOCKS_PER_GROUP(sb)) || - unlikely(start >= max_blks)) + if (minlen > EXT3_BLOCKS_PER_GROUP(sb) || + start >= max_blks || + range->len < sb->s_blocksize) return -EINVAL; if (end >= max_blks) end = max_blks - 1; -- 2.34.1