| Message ID | de9e8705169b5dc873f6ce9f9a17598de89aa6a7.1644081032.git.christophe.jaillet@wanadoo.fr (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] iommu/arm-smmu-v3: Avoid open coded arithmetic in memory allocation | expand |
On 2022-02-05 17:10, Christophe JAILLET wrote: > kmalloc_array()/kcalloc() should be used to avoid potential overflow when > a multiplication is needed to compute the size of the requested memory. > > So turn a devm_kzalloc()+explicit size computation into an equivalent > devm_kcalloc(). > > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> > --- > This is NOT compile tested. > I don't have the needed cross compiling tools. FYI, https://cdn.kernel.org/pub/tools/crosstool/ Either way, the patch looks reasonable, thanks! Acked-by: Robin Murphy <robin.murphy@arm.com> > --- > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > index 6dc6d8b6b368..14d06aad0726 100644 > --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c > @@ -2981,10 +2981,10 @@ static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu) > { > unsigned int i; > struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg; > - size_t size = sizeof(*cfg->l1_desc) * cfg->num_l1_ents; > void *strtab = smmu->strtab_cfg.strtab; > > - cfg->l1_desc = devm_kzalloc(smmu->dev, size, GFP_KERNEL); > + cfg->l1_desc = devm_kcalloc(smmu->dev, cfg->num_l1_ents, > + sizeof(*cfg->l1_desc), GFP_KERNEL); > if (!cfg->l1_desc) > return -ENOMEM; >
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 6dc6d8b6b368..14d06aad0726 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -2981,10 +2981,10 @@ static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu) { unsigned int i; struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg; - size_t size = sizeof(*cfg->l1_desc) * cfg->num_l1_ents; void *strtab = smmu->strtab_cfg.strtab; - cfg->l1_desc = devm_kzalloc(smmu->dev, size, GFP_KERNEL); + cfg->l1_desc = devm_kcalloc(smmu->dev, cfg->num_l1_ents, + sizeof(*cfg->l1_desc), GFP_KERNEL); if (!cfg->l1_desc) return -ENOMEM;
kmalloc_array()/kcalloc() should be used to avoid potential overflow when a multiplication is needed to compute the size of the requested memory. So turn a devm_kzalloc()+explicit size computation into an equivalent devm_kcalloc(). Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> --- This is NOT compile tested. I don't have the needed cross compiling tools. --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)