diff options
| author | Dan Carpenter <error27@gmail.com> | 2010-03-15 11:21:13 +0300 |
|---|---|---|
| committer | Jan Kara <jack@suse.cz> | 2010-04-08 15:35:20 +0200 |
| commit | 69ecbbedac8e353bbd924fad16fed0c7c54e6382 (patch) | |
| tree | f008c3ad0750585ea3d403718251922f215cb626 /fs/udf/balloc.c | |
| parent | 0fdf86754f70e813845af4abaa805165ce57a0bb (diff) | |
| download | lwn-69ecbbedac8e353bbd924fad16fed0c7c54e6382.tar.gz lwn-69ecbbedac8e353bbd924fad16fed0c7c54e6382.zip | |
udf: potential integer overflow
bloc->logicalBlockNum is unsigned so it's never less than zero.
When I saw that, it made me worry that "bloc->logicalBlockNum + count"
could overflow. That's why I changed the check for less than zero
to an overflow check. (The test works because "count" is also
unsigned.)
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Diffstat (limited to 'fs/udf/balloc.c')
| -rw-r--r-- | fs/udf/balloc.c | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/fs/udf/balloc.c b/fs/udf/balloc.c index 19626e2491c4..9a9378b4eb5a 100644 --- a/fs/udf/balloc.c +++ b/fs/udf/balloc.c @@ -125,9 +125,8 @@ static void udf_bitmap_free_blocks(struct super_block *sb, mutex_lock(&sbi->s_alloc_mutex); partmap = &sbi->s_partmaps[bloc->partitionReferenceNum]; - if (bloc->logicalBlockNum < 0 || - (bloc->logicalBlockNum + count) > - partmap->s_partition_len) { + if (bloc->logicalBlockNum + count < count || + (bloc->logicalBlockNum + count) > partmap->s_partition_len) { udf_debug("%d < %d || %d + %d > %d\n", bloc->logicalBlockNum, 0, bloc->logicalBlockNum, count, partmap->s_partition_len); @@ -393,9 +392,8 @@ static void udf_table_free_blocks(struct super_block *sb, mutex_lock(&sbi->s_alloc_mutex); partmap = &sbi->s_partmaps[bloc->partitionReferenceNum]; - if (bloc->logicalBlockNum < 0 || - (bloc->logicalBlockNum + count) > - partmap->s_partition_len) { + if (bloc->logicalBlockNum + count < count || + (bloc->logicalBlockNum + count) > partmap->s_partition_len) { udf_debug("%d < %d || %d + %d > %d\n", bloc->logicalBlockNum, 0, bloc->logicalBlockNum, count, partmap->s_partition_len); |