Commit b7a4c5d8 authored by Xin Xiong's avatar Xin Xiong Committed by Chen Zhongjin
Browse files

drm/amd/amdgpu/amdgpu_cs: fix refcount leak of a dma_fence obj 

stable inclusion
from stable-v4.19.238
commit 72d77ddb2224ebc00648f4f78f8a9a259dccbdf7
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBP45K
CVE: CVE-2022-49137
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=72d77ddb2224ebc00648f4f78f8a9a259dccbdf7



--------------------------------

[ Upstream commit dfced44f ]

This issue takes place in an error path in
amdgpu_cs_fence_to_handle_ioctl(). When `info->in.what` falls into
default case, the function simply returns -EINVAL, forgetting to
decrement the reference count of a dma_fence obj, which is bumped
earlier by amdgpu_cs_get_fence(). This may result in reference count
leaks.

Fix it by decreasing the refcount of specific object before returning
the error code.

Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Signed-off-by: default avatarXin Xiong <xiongx18@fudan.edu.cn>
Signed-off-by: default avatarXin Tan <tanxin.ctf@gmail.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarChen Zhongjin <chenzhongjin@huawei.com>
parent 98d5b044

drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c

+1 −0
Original line number Diff line number Diff line
@@ -1469,6 +1469,7 @@ int amdgpu_cs_fence_to_handle_ioctl(struct drm_device *dev, void *data, 
		return 0;



	default:

		dma_fence_put(fence);

		return -EINVAL;

	}

}