| Message ID | 20190108210946.GA4014@embeddedor |
|---|---|
| State | Accepted |
| Delegated to: | Boris Brezillon |
| Headers | show |
| Series | mtd: lpddr: Use struct_size() in kzalloc() | expand |
From: Boris Brezillon <boris.brezillon@bootlin.com> On Tue, 2019-01-08 at 21:09:46 UTC, "Gustavo A. R. Silva" wrote: > One of the more common cases of allocation size calculations is finding the > size of a structure that has a zero-sized array at the end, along with memory > for some number of elements for that array. For example: > > struct foo { > int stuff; > void *entry[]; > }; > > instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL); > > Instead of leaving these open-coded and prone to type mistakes, we can now > use the new struct_size() helper: > > instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL); > > This code was detected with the help of Coccinelle. > > Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Applied to http://git.infradead.org/linux-mtd.git mtd/next, thanks. Boris
diff --git a/drivers/mtd/lpddr/qinfo_probe.c b/drivers/mtd/lpddr/qinfo_probe.c index 69f2112340b1..175bdc3b72f4 100644 --- a/drivers/mtd/lpddr/qinfo_probe.c +++ b/drivers/mtd/lpddr/qinfo_probe.c @@ -181,8 +181,8 @@ static struct lpddr_private *lpddr_probe_chip(struct map_info *map) lpddr.numchips = 1; numvirtchips = lpddr.numchips * lpddr.qinfo->HWPartsNum; - retlpddr = kzalloc(sizeof(struct lpddr_private) + - numvirtchips * sizeof(struct flchip), GFP_KERNEL); + retlpddr = kzalloc(struct_size(retlpddr, chips, numvirtchips), + GFP_KERNEL); if (!retlpddr) return NULL;
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct foo { int stuff; void *entry[]; }; instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> --- drivers/mtd/lpddr/qinfo_probe.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)