[PATCH 6.12 473/567] drm/i915: Fix format string truncation warning

Greg Kroah-Hartman
2026-01-06T17:40:22Z

From: Ard Biesheuvel <ardb@kernel.org>

commit 1c7f9e528f8f488b060b786bfb90b40540854db3 upstream.

GCC notices that the 16-byte uabi_name field could theoretically be too
small for the formatted string if the instance number exceeds 100.

So grow the field to 20 bytes.

drivers/gpu/drm/i915/intel_memory_region.c: In function ‘intel_memory_region_create’:
drivers/gpu/drm/i915/intel_memory_region.c:273:61: error: ‘%u’ directive output may be truncated writing between 1 and 5 bytes into a region of size between 3 and 11 [-Werror=format-truncation=]
273 | snprintf(mem->uabi_name, sizeof(mem->uabi_name), "%s%u",
| ^~
drivers/gpu/drm/i915/intel_memory_region.c:273:58: note: directive argument in the range [0, 65535]
273 | snprintf(mem->uabi_name, sizeof(mem->uabi_name), "%s%u",
| ^~~~~~
drivers/gpu/drm/i915/intel_memory_region.c:273:9: note: ‘snprintf’ output between 7 and 19 bytes into a destination of size 16
273 | snprintf(mem->uabi_name, sizeof(mem->uabi_name), "%s%u",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
274 | intel_memory_type_str(type), instance);
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Fixes: 3b38d3515753 ("drm/i915: Add stable memory region names")
Cc: <stable@vger.kernel.org> # v6.8+
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>
Link: https://lore.kernel.org/r/20251205113500.684286-2-ardb@kernel.org
(cherry picked from commit 18476087f1a18dc279d200d934ad94fba1fb51d5)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/i915/intel_memory_region.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/i915/intel_memory_region.h
+++ b/drivers/gpu/drm/i915/intel_memory_region.h
@@ -72,7 +72,7 @@ struct intel_memory_region {
u16 instance;
enum intel_region_id id;
char name[16];
- char uabi_name[16];
+ char uabi_name[20];
bool private; /* not for userspace */

struct {