| Message ID | 20180824010938.GA25581@embeddedor.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mtd: rawnand: atmel: use struct_size() in devm_kzalloc() | expand |
On Thu, Aug 23, 2018 at 6:09 PM, 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 issue was detected with the help of Coccinelle. > > Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Reviewed-by: Kees Cook <keescook@chromium.org> -Kees > --- > drivers/mtd/nand/raw/atmel/nand-controller.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/drivers/mtd/nand/raw/atmel/nand-controller.c b/drivers/mtd/nand/raw/atmel/nand-controller.c > index a068b21..b17cfd0 100644 > --- a/drivers/mtd/nand/raw/atmel/nand-controller.c > +++ b/drivers/mtd/nand/raw/atmel/nand-controller.c > @@ -1586,9 +1586,7 @@ static struct atmel_nand *atmel_nand_create(struct atmel_nand_controller *nc, > return ERR_PTR(-EINVAL); > } > > - nand = devm_kzalloc(nc->dev, > - sizeof(*nand) + (numcs * sizeof(*nand->cs)), > - GFP_KERNEL); > + nand = devm_kzalloc(nc->dev, struct_size(nand, cs, numcs), GFP_KERNEL); > if (!nand) { > dev_err(nc->dev, "Failed to allocate NAND object\n"); > return ERR_PTR(-ENOMEM); > -- > 2.7.4 >
Hi Gustavo, On Thu, 23 Aug 2018 20:09:38 -0500 "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 issue was detected with the help of Coccinelle. > > Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Can we have all NAND controller drivers patched in a single patch instead of having one patch per-driver? Thanks, Boris
Hi Gustavo, "Gustavo A. R. Silva" <gustavo@embeddedor.com> wrote on Thu, 23 Aug 2018 20:09:38 -0500: > 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> > --- Applied to nand/next. Thanks, Miquèl
diff --git a/drivers/mtd/nand/raw/atmel/nand-controller.c b/drivers/mtd/nand/raw/atmel/nand-controller.c index a068b21..b17cfd0 100644 --- a/drivers/mtd/nand/raw/atmel/nand-controller.c +++ b/drivers/mtd/nand/raw/atmel/nand-controller.c @@ -1586,9 +1586,7 @@ static struct atmel_nand *atmel_nand_create(struct atmel_nand_controller *nc, return ERR_PTR(-EINVAL); } - nand = devm_kzalloc(nc->dev, - sizeof(*nand) + (numcs * sizeof(*nand->cs)), - GFP_KERNEL); + nand = devm_kzalloc(nc->dev, struct_size(nand, cs, numcs), GFP_KERNEL); if (!nand) { dev_err(nc->dev, "Failed to allocate NAND object\n"); return ERR_PTR(-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/mtd/nand/raw/atmel/nand-controller.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)