ext4: Avoid underflow in ext4_trim_fs()
commit 5de35e8d5c02d271c20e18337e01bc20e6ef472e upstream.
Currently if len argument in ext4_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 <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 6b0a57e..e77c4fe 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4984,8 +4984,9 @@
end = start + (range->len >> sb->s_blocksize_bits) - 1;
minlen = range->minlen >> sb->s_blocksize_bits;
- if (unlikely(minlen > EXT4_CLUSTERS_PER_GROUP(sb)) ||
- unlikely(start >= max_blks))
+ if (minlen > EXT4_CLUSTERS_PER_GROUP(sb) ||
+ start >= max_blks ||
+ range->len < sb->s_blocksize)
return -EINVAL;
if (end >= max_blks)
end = max_blks - 1;