1

block: fix overflow in blk_ioctl_discard()

There is no check for overflow of 'start + len' in blk_ioctl_discard().
Hung task occurs if submit an discard ioctl with the following param:
  start = 0x80000000000ff000, len = 0x8000000000fff000;
Add the overflow validation now.

Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240329012319.2034550-1-linan666@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Li Nan 2024-03-29 09:23:19 +08:00 committed by Jens Axboe
parent fbbd5d3ad9
commit 22d24a544b

View File

@ -96,7 +96,7 @@ static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
unsigned long arg) unsigned long arg)
{ {
uint64_t range[2]; uint64_t range[2];
uint64_t start, len; uint64_t start, len, end;
struct inode *inode = bdev->bd_inode; struct inode *inode = bdev->bd_inode;
int err; int err;
@ -117,7 +117,8 @@ static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
if (len & 511) if (len & 511)
return -EINVAL; return -EINVAL;
if (start + len > bdev_nr_bytes(bdev)) if (check_add_overflow(start, len, &end) ||
end > bdev_nr_bytes(bdev))
return -EINVAL; return -EINVAL;
filemap_invalidate_lock(inode->i_mapping); filemap_invalidate_lock(inode->i_mapping);