drm/i915/guc: prevent a possible int overflow in wq offsets

[ Upstream commit d3d37f7468 ]

It may be possible for the sum of the values derived from
i915_ggtt_offset() and __get_parent_scratch_offset()/
i915_ggtt_offset() to go over the u32 limit before being assigned
to wq offsets of u64 type.

Mitigate these issues by expanding one of the right operands
to u64 to avoid any overflow issues just in case.

Found by Linux Verification Center (linuxtesting.org) with static
analysis tool SVACE.

Fixes: c2aa552ff0 ("drm/i915/guc: Add multi-lrc context registration")
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Signed-off-by: Nikita Zhandarovich <n.zhandarovich@fintech.ru>
Link: https://patchwork.freedesktop.org/patch/msgid/20240725155925.14707-1-n.zhandarovich@fintech.ru
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
(cherry picked from commit 1f1c1bd566)
Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Nikita Zhandarovich
2024-07-25 08:59:25 -07:00
committed by Greg Kroah-Hartman
parent 4e96ea328a
commit bcf0e7f90b
@@ -2842,9 +2842,9 @@ static void prepare_context_registration_info_v70(struct intel_context *ce,
ce->parallel.guc.wqi_tail = 0;
ce->parallel.guc.wqi_head = 0;
wq_desc_offset = i915_ggtt_offset(ce->state) +
wq_desc_offset = (u64)i915_ggtt_offset(ce->state) +
__get_parent_scratch_offset(ce);
wq_base_offset = i915_ggtt_offset(ce->state) +
wq_base_offset = (u64)i915_ggtt_offset(ce->state) +
__get_wq_offset(ce);
info->wq_desc_lo = lower_32_bits(wq_desc_offset);
info->wq_desc_hi = upper_32_bits(wq_desc_offset);