| Message ID | 2795c5ba939fe23dda6c86135d56e68433f7d68a.1546667177.git.gustavo@embeddedor.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix NULL pointer dereference and use struct_size | expand |
On Sat, Jan 5, 2019 at 6:55 AM Gustavo A. R. Silva <gustavo@embeddedor.com> 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 code was detected with the help of Coccinelle. > > Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> > --- > Changes in v2: > - Fix devm_kzalloc parameter reported by kbuild test robot. Patch applied. Yours, Linus Walleij
diff --git a/arch/arm/mach-integrator/impd1.c b/arch/arm/mach-integrator/impd1.c index eb0149561be2..a0a1e2acdb5e 100644 --- a/arch/arm/mach-integrator/impd1.c +++ b/arch/arm/mach-integrator/impd1.c @@ -390,7 +390,7 @@ static int __ref impd1_probe(struct lm_device *dev) char *mmciname; lookup = devm_kzalloc(&dev->dev, - sizeof(*lookup) + 3 * sizeof(struct gpiod_lookup), + struct_size(lookup, table, 3), GFP_KERNEL); if (!lookup) 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 code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> --- Changes in v2: - Fix devm_kzalloc parameter reported by kbuild test robot. arch/arm/mach-integrator/impd1.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)