Commit 2b4abf87 authored Apr 11, 2026 by Dmitry Baryshkov Committed by Rob Clark May 13, 2026

drm/msm/adreno: fix userspace-triggered crash on a2xx-a4xx

Before a5xx Adreno driver will not try fetching UBWC params (because
those generations didn't support UBWC anyway), however it's still
possible to query UBWC-related params from the userspace, triggering
possible NULL pointer dereference. Check for UBWC config in
adreno_get_param() and return sane defaults if there is none.

Fixes: a452510a ("drm/msm/adreno: Switch to the common UBWC config struct")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Rob Clark <rob.clark@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/717778/

Message-ID: <20260411-adreno-fix-ubwc-v3-1-4983156f3f80@oss.qualcomm.com>
Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>

parent e64bca63

drivers/gpu/drm/msm/adreno/adreno_gpu.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -424,15 +424,21 @@ int adreno_get_param(struct msm_gpu gpu, struct msm_context ctx,
		*value = vm->mm_range;
		return 0;
		case MSM_PARAM_HIGHEST_BANK_BIT:
		if (!adreno_gpu->ubwc_config)
		return UERR(ENOENT, drm, "no UBWC on this platform");
		*value = adreno_gpu->ubwc_config->highest_bank_bit;
		return 0;
		case MSM_PARAM_RAYTRACING:
		*value = adreno_gpu->has_ray_tracing;
		return 0;
		case MSM_PARAM_UBWC_SWIZZLE:
		if (!adreno_gpu->ubwc_config)
		return UERR(ENOENT, drm, "no UBWC on this platform");
		*value = adreno_gpu->ubwc_config->ubwc_swizzle;
		return 0;
		case MSM_PARAM_MACROTILE_MODE:
		if (!adreno_gpu->ubwc_config)
		return UERR(ENOENT, drm, "no UBWC on this platform");
		*value = adreno_gpu->ubwc_config->macrotile_mode;
		return 0;
		case MSM_PARAM_UCHE_TRAP_BASE: