On 6/27/23 20:09, Min Li wrote:
> Before calling add partition or resize partition, there is no check
> on whether the length is aligned with the logical block size.
> If the logical block size of the disk is larger than 512 bytes,
> then the partition size maybe not the multiple of the logical block size,
> and when the last sector is read, bio_truncate() will adjust the bio size,
> resulting in an IO error if the size of the read command is smaller than
> the logical block size.If integrity data is supported, this will also
> result in a null pointer dereference when calling bio_integrity_free.
>
> Signed-off-by: Min Li <min15.li@xxxxxxxxxxx>
See Greg's comment: this likely need a "Fixes:" tag. And I think that the tag
is: fa9156ae597c ("block: refactor blkpg_ioctl"). But please double check.
>
> ---
> Changes from v1:
>
> - Add a space after /* and before */.
> - Move length alignment check before the "start = p.start >> SECTOR_SHIFT"
> - Move check for p.start being aligned together with this length alignment check.
> ---
> block/ioctl.c | 10 +++++++---
> 1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/block/ioctl.c b/block/ioctl.c
> index 3be11941fb2d..c40b382dd58f 100644
> --- a/block/ioctl.c
> +++ b/block/ioctl.c
> @@ -33,14 +33,18 @@ static int blkpg_do_ioctl(struct block_device *bdev,
> if (op == BLKPG_DEL_PARTITION)
> return bdev_del_partition(disk, p.pno);
>
> + /* check if partition is aligned to blocksize */
> + if (p.start & (bdev_logical_block_size(bdev) - 1))
> + return -EINVAL;
> + /* check if length is aligned to blocksize */
> + if (p.length & (bdev_logical_block_size(bdev) - 1))
> + return -EINVAL;
long long blksz_mask = bdev_logical_block_size(bdev) - 1;
/* Check that the partition is aligned to the block size */
if ((p.start & blksz_mask) || (p.length & blksz_mask))
return -EINVAL;
would be cleaner and avoid the rather redundant comments.
> +
> start = p.start >> SECTOR_SHIFT;
> length = p.length >> SECTOR_SHIFT;
>
> switch (op) {
> case BLKPG_ADD_PARTITION:
> - /* check if partition is aligned to blocksize */
> - if (p.start & (bdev_logical_block_size(bdev) - 1))
> - return -EINVAL;
> return bdev_add_partition(disk, p.pno, start, length);
> case BLKPG_RESIZE_PARTITION:
> return bdev_resize_partition(disk, p.pno, start, length);
--
Damien Le Moal
Western Digital Research
