From: jsg <jsg@openbsd.org>
Date: Thu, 24 Aug 2023 06:10:10 +0000 (+0000)
Subject: drm/amdgpu: Fix potential fence use-after-free v2
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=d62e2f46081d40b53750a85e515f085fa15f46b6;p=openbsd

drm/amdgpu: Fix potential fence use-after-free v2

From shanzhulig
dd0b3b367c3839e439f36af908b39c98929a5e54 in linux-6.1.y/6.1.47
2e54154b9f27262efd0cb4f903cc7d5ad1fe9628 in mainline linux
---

diff --git a/sys/dev/pci/drm/amd/amdgpu/amdgpu_cs.c b/sys/dev/pci/drm/amd/amdgpu/amdgpu_cs.c
index 22f8a5a610e..0508926871a 100644
--- a/sys/dev/pci/drm/amd/amdgpu/amdgpu_cs.c
+++ b/sys/dev/pci/drm/amd/amdgpu/amdgpu_cs.c
@@ -1609,15 +1609,15 @@ static int amdgpu_cs_wait_all_fences(struct amdgpu_device *adev,
 			continue;
 
 		r = dma_fence_wait_timeout(fence, true, timeout);
+		if (r > 0 && fence->error)
+			r = fence->error;
+
 		dma_fence_put(fence);
 		if (r < 0)
 			return r;
 
 		if (r == 0)
 			break;
-
-		if (fence->error)
-			return fence->error;
 	}
 
 	memset(wait, 0, sizeof(*wait));