From e1dd871442c05ad5f53bc1eac22f71b53eb48a8a Mon Sep 17 00:00:00 2001 From: John Harrison Date: Tue, 1 Mar 2022 16:33:57 -0800 Subject: [PATCH] drm/i915/guc: Fix potential invalid pointer dereferences when decoding G2Hs Some G2H handlers were reading the context id field from the payload before checking the payload met the minimum length required. Signed-off-by: John Harrison Reviewed-by: Daniele Ceraolo Spurio Link: https://patchwork.freedesktop.org/patch/msgid/20220302003357.4188363-9-John.C.Harrison@Intel.com --- drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c index e224e6d..9d8a271 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c @@ -3895,12 +3895,13 @@ int intel_guc_deregister_done_process_msg(struct intel_guc *guc, u32 len) { struct intel_context *ce; - u32 ctx_id = msg[0]; + u32 ctx_id; if (unlikely(len < 1)) { drm_err(&guc_to_gt(guc)->i915->drm, "Invalid length %u\n", len); return -EPROTO; } + ctx_id = msg[0]; ce = g2h_context_lookup(guc, ctx_id); if (unlikely(!ce)) @@ -3946,12 +3947,13 @@ int intel_guc_sched_done_process_msg(struct intel_guc *guc, { struct intel_context *ce; unsigned long flags; - u32 ctx_id = msg[0]; + u32 ctx_id; if (unlikely(len < 2)) { drm_err(&guc_to_gt(guc)->i915->drm, "Invalid length %u\n", len); return -EPROTO; } + ctx_id = msg[0]; ce = g2h_context_lookup(guc, ctx_id); if (unlikely(!ce)) -- 2.7.4