From 2bfc0f26b82d3c505bf64c0876b6ca7bc2dc4c3a Mon Sep 17 00:00:00 2001
From: "Stanley.Yang" <Stanley.Yang@amd.com>
Date: Wed, 16 Nov 2022 17:08:22 +0800
Subject: drm/amdgpu: fix use-after-free during gpu recovery
Git-commit: 3cb93f390453cde4d6afda1587aaa00e75e09617
Patch-mainline: v6.1-rc7
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225 jsc#PED-2849
[Why]
[ 754.862560] refcount_t: underflow; use-after-free.
[ 754.862898] Call Trace:
[ 754.862903] <TASK>
[ 754.862913] amdgpu_job_free_cb+0xc2/0xe1 [amdgpu]
[ 754.863543] drm_sched_main.cold+0x34/0x39 [amd_sched]
[How]
The fw_fence may be not init, check whether dma_fence_init
is performed before job free
Signed-off-by: Stanley.Yang <Stanley.Yang@amd.com>
Reviewed-by: Tao Zhou <tao.zhou1@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_job.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
index abb99cff8b4b..adac650cf544 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.c
@@ -169,7 +169,11 @@ static void amdgpu_job_free_cb(struct drm_sched_job *s_job)
amdgpu_sync_free(&job->sync);
amdgpu_sync_free(&job->sched_sync);
- dma_fence_put(&job->hw_fence);
+ /* only put the hw fence if has embedded fence */
+ if (!job->hw_fence.ops)
+ kfree(job);
+ else
+ dma_fence_put(&job->hw_fence);
}
void amdgpu_job_set_gang_leader(struct amdgpu_job *job,
--
2.38.1