[PATCH] drm/amd/amdkfd: fix possible memory leak in svm_range_restore_pages

[Xiyu Yang]

The memory leak issue may take place in an error handling path. When
p->xnack_enabled is NULL, the function simply returns with -EFAULT and
forgets to decrement the reference count of a kfd_process object bumped
by kfd_lookup_process_by_pasid, which may incur memory leaks.

Fix it by jumping to label "out", in which kfd_unref_process() decreases
the refcount.

Signed-off-by: Xiyu Yang <xiyuyang19 at fudan.edu.cn>
Signed-off-by: Xin Xiong <xiongx18 at fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf at gmail.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index e883731c3f8f..0f7f1e5621ea 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -2426,7 +2426,8 @@ svm_range_restore_pages(struct amdgpu_device *adev, unsigned int pasid,
 	}
 	if (!p->xnack_enabled) {
 		pr_debug("XNACK not enabled for pasid 0x%x\n", pasid);
-		return -EFAULT;
+		r = -EFAULT;
+		goto out;
 	}
 	svms = &p->svms;
 
-- 
2.7.4