From: Lukas Czerner Date: Thu, 11 Oct 2012 10:28:38 +0000 (+0200) Subject: ext3: Avoid underflow of in ext3_trim_fs() X-Git-Tag: v3.7-rc7~30^2 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=ae49eeec785025373e28dc24c8351c6bba688d99;p=profile%2Fivi%2Fkernel-adaptation-intel-automotive.git 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 --- diff --git a/fs/ext3/balloc.c b/fs/ext3/balloc.c index 7320a66..22548f5 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;