[PATCH 1/5] drm/amdgpu: Move a variable assignment behind a null pointer check in amdgpu_ras_interrupt_dispatch()

[Markus Elfring]

Date: Tue, 11 Apr 2023 10:52:48 +0200

The address of a data structure member was determined before
a corresponding null pointer check in the implementation of
the function “amdgpu_ras_interrupt_dispatch”.

Thus avoid the risk for undefined behaviour by moving the assignment
for the variable “data” behind the null pointer check.

This issue was detected by using the Coccinelle software.

Fixes: c030f2e4166c3f5597c7e7a70bcd9ab383695de4 ("drm/amdgpu: add amdgpu_ras.c to support ras (v2)")
Signed-off-by: Markus Elfring <elfring at users.sourceforge.net>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
index 4069bce9479f..a920c7888d07 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ras.c
@@ -1730,11 +1730,12 @@ int amdgpu_ras_interrupt_dispatch(struct amdgpu_device *adev,
 		struct ras_dispatch_if *info)
 {
 	struct ras_manager *obj = amdgpu_ras_find_obj(adev, &info->head);
-	struct ras_ih_data *data = &obj->ih_data;
+	struct ras_ih_data *data;

 	if (!obj)
 		return -EINVAL;

+	data = &obj->ih_data;
 	if (data->inuse == 0)
 		return 0;

--
2.40.0