block: genhd: Use struct_size() helper

Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes, in particular in the
context in which this code is being used.

So, replace the following form:

sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0])

with:

struct_size(new_ptbl, part, target)

Also, notice that variable size is unnecessary, hence it is removed.

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Gustavo A. R. Silva 2019-05-31 13:47:54 -05:00 committed by Jens Axboe
parent 7602843fd8
commit 78b90a2ce8

View File

@ -1281,7 +1281,6 @@ int disk_expand_part_tbl(struct gendisk *disk, int partno)
struct disk_part_tbl *new_ptbl;
int len = old_ptbl ? old_ptbl->len : 0;
int i, target;
size_t size;
/*
* check for int overflow, since we can get here from blkpg_ioctl()
@ -1298,8 +1297,8 @@ int disk_expand_part_tbl(struct gendisk *disk, int partno)
if (target <= len)
return 0;
size = sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0]);
new_ptbl = kzalloc_node(size, GFP_KERNEL, disk->node_id);
new_ptbl = kzalloc_node(struct_size(new_ptbl, part, target), GFP_KERNEL,
disk->node_id);
if (!new_ptbl)
return -ENOMEM;