| Message ID | 20240211175143.9229-1-erick.archer@gmx.com (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | 8379054869a0e8d0ebf8f2160ccc778ed6268b96 |
| Headers | show |
| Series | iommu/vt-d: Use kcalloc() instead of kzalloc() | expand |
On Sun, Feb 11, 2024 at 06:51:43PM +0100, Erick Archer wrote: > This is an effort to get rid of all multiplications from allocation > functions in order to prevent integer overflows [1]. > > Here the multiplication is obviously safe because DMAR_LATENCY_NUM > is the number of latency types defined in the "latency_type" enum. > > enum latency_type { > DMAR_LATENCY_INV_IOTLB = 0, > DMAR_LATENCY_INV_DEVTLB, > DMAR_LATENCY_INV_IEC, > DMAR_LATENCY_PRQ, > DMAR_LATENCY_NUM > }; > > However, using kcalloc() is more appropriate [2] and improves > readability. This patch has no effect on runtime behavior. > > Link: https://github.com/KSPP/linux/issues/162 [1] > Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [2] > Signed-off-by: Erick Archer <erick.archer@gmx.com> Looks reasonable. Reviewed-by: Kees Cook <keescook@chromium.org>
On 2/11/24 11:51, Erick Archer wrote: > This is an effort to get rid of all multiplications from allocation > functions in order to prevent integer overflows [1]. > > Here the multiplication is obviously safe because DMAR_LATENCY_NUM > is the number of latency types defined in the "latency_type" enum. > > enum latency_type { > DMAR_LATENCY_INV_IOTLB = 0, > DMAR_LATENCY_INV_DEVTLB, > DMAR_LATENCY_INV_IEC, > DMAR_LATENCY_PRQ, > DMAR_LATENCY_NUM > }; > > However, using kcalloc() is more appropriate [2] and improves > readability. This patch has no effect on runtime behavior. > > Link: https://github.com/KSPP/linux/issues/162 [1] > Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [2] > Signed-off-by: Erick Archer <erick.archer@gmx.com> LGTM: Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Thanks!
On 2/12/24 1:51 AM, Erick Archer wrote: > This is an effort to get rid of all multiplications from allocation > functions in order to prevent integer overflows [1]. > > Here the multiplication is obviously safe because DMAR_LATENCY_NUM > is the number of latency types defined in the "latency_type" enum. > > enum latency_type { > DMAR_LATENCY_INV_IOTLB = 0, > DMAR_LATENCY_INV_DEVTLB, > DMAR_LATENCY_INV_IEC, > DMAR_LATENCY_PRQ, > DMAR_LATENCY_NUM > }; > > However, using kcalloc() is more appropriate [2] and improves > readability. This patch has no effect on runtime behavior. > > Link:https://github.com/KSPP/linux/issues/162 [1] > Link:https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [2] > Signed-off-by: Erick Archer<erick.archer@gmx.com> > --- > drivers/iommu/intel/perf.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) I have queued this patch for v6.9. Best regards, baolu
diff --git a/drivers/iommu/intel/perf.c b/drivers/iommu/intel/perf.c index 94ee70ac38e3..adc4de6bbd88 100644 --- a/drivers/iommu/intel/perf.c +++ b/drivers/iommu/intel/perf.c @@ -33,7 +33,7 @@ int dmar_latency_enable(struct intel_iommu *iommu, enum latency_type type) spin_lock_irqsave(&latency_lock, flags); if (!iommu->perf_statistic) { - iommu->perf_statistic = kzalloc(sizeof(*lstat) * DMAR_LATENCY_NUM, + iommu->perf_statistic = kcalloc(DMAR_LATENCY_NUM, sizeof(*lstat), GFP_ATOMIC); if (!iommu->perf_statistic) { ret = -ENOMEM;
This is an effort to get rid of all multiplications from allocation functions in order to prevent integer overflows [1]. Here the multiplication is obviously safe because DMAR_LATENCY_NUM is the number of latency types defined in the "latency_type" enum. enum latency_type { DMAR_LATENCY_INV_IOTLB = 0, DMAR_LATENCY_INV_DEVTLB, DMAR_LATENCY_INV_IEC, DMAR_LATENCY_PRQ, DMAR_LATENCY_NUM }; However, using kcalloc() is more appropriate [2] and improves readability. This patch has no effect on runtime behavior. Link: https://github.com/KSPP/linux/issues/162 [1] Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [2] Signed-off-by: Erick Archer <erick.archer@gmx.com> --- drivers/iommu/intel/perf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.25.1