[PATCH v1 1/1] iommu/vt-d: Increase buffer size for device name

[PATCH v1 1/1] iommu/vt-d: Increase buffer size for device name

[Andy Shevchenko]

GCC is not happy with the current code, e.g.:

.../iommu/intel/dmar.c:1063:9: note: ‘sprintf’ output between 6 and 15 bytes into a destination of size 13
 1063 |         sprintf(iommu->name, "dmar%d", iommu->seq_id);

When `make W=1` is supplied, this prevents kernel building. Fix it by
increasing the buffer size for device name and use sizeoF() instead of
hard coded constants.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/iommu/intel/dmar.c  | 2 +-
 drivers/iommu/intel/iommu.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index eaf862e8dea1..e16c2b1d7633 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -1060,7 +1060,7 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd)
 		err = iommu->seq_id;
 		goto error;
 	}
-	sprintf(iommu->name, "dmar%d", iommu->seq_id);
+	snprintf(iommu->name, sizeof(iommu->name), "dmar%d", iommu->seq_id);
 
 	err = map_iommu(iommu, drhd);
 	if (err) {
diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h
index 1497f3112b12..61701c1c22d3 100644
--- a/drivers/iommu/intel/iommu.h
+++ b/drivers/iommu/intel/iommu.h
@@ -720,7 +720,7 @@ struct intel_iommu {
 	int		msagaw; /* max sagaw of this iommu */
 	unsigned int	irq, pr_irq, perf_irq;
 	u16		segment;     /* PCI segment# */
-	unsigned char 	name[13];    /* Device Name */
+	unsigned char 	name[16];    /* Device Name */
 
 #ifdef CONFIG_INTEL_IOMMU
 	unsigned long 	*domain_ids; /* bitmap of domains */
-- 
2.43.0.rc1.1336.g36b5255a03ac

Re: [PATCH v1 1/1] iommu/vt-d: Increase buffer size for device name

[Baolu Lu]

On 2024/10/14 18:45, Andy Shevchenko wrote:
> GCC is not happy with the current code, e.g.:
> 
> .../iommu/intel/dmar.c:1063:9: note: ‘sprintf’ output between 6 and 15 bytes into a destination of size 13
>   1063 |         sprintf(iommu->name, "dmar%d", iommu->seq_id);
> 
> When `make W=1` is supplied, this prevents kernel building. Fix it by
> increasing the buffer size for device name and use sizeoF() instead of
> hard coded constants.
> 
> Signed-off-by: Andy Shevchenko<andriy.shevchenko@linux.intel.com>
> ---
>   drivers/iommu/intel/dmar.c  | 2 +-
>   drivers/iommu/intel/iommu.h | 2 +-
>   2 files changed, 2 insertions(+), 2 deletions(-)

Queued for v6.13. Thank you!

--
baolu