| Message ID | 20181224065217.GA10629@embeddedor.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | dmaengine: dma-jz4780: Use struct_size() in devm_kzalloc() | expand |
On 24-12-18, 00:52, 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 = devm_kzalloc(dev, 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 = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL); > > This issue was detected with the help of Coccinelle. Applied, thanks
diff --git a/drivers/dma/dma-jz4780.c b/drivers/dma/dma-jz4780.c index a8b6225faa12..9ce0a386225b 100644 --- a/drivers/dma/dma-jz4780.c +++ b/drivers/dma/dma-jz4780.c @@ -838,9 +838,8 @@ static int jz4780_dma_probe(struct platform_device *pdev) if (!soc_data) return -EINVAL; - jzdma = devm_kzalloc(dev, sizeof(*jzdma) - + sizeof(*jzdma->chan) * soc_data->nb_channels, - GFP_KERNEL); + jzdma = devm_kzalloc(dev, struct_size(jzdma, chan, + soc_data->nb_channels), GFP_KERNEL); if (!jzdma) return -ENOMEM;
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 = devm_kzalloc(dev, 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 = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL); This issue was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> --- drivers/dma/dma-jz4780.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)