Fix two issues with memory allocation in amdgpu_discovery_get_nps_info()
for mem_ranges:

 - Add a check for allocation failure to avoid dereferencing a null
   pointer.

 - As suggested by Christophe, use kvcalloc() for memory allocation,
   which checks for multiplication overflow.

Additionally, assign the output parameters nps_type and range_cnt after
the kvcalloc() call to prevent modifying the output parameters in case
of an error return.

Fixes: b194d21b9bcc ("drm/amdgpu: Use NPS ranges from discovery table")
Suggested-by: Christophe JAILLET <christophe.jail...@wanadoo.fr>
Reviewed-by: Lijo Lazar <lijo.la...@amd.com>
Signed-off-by: Li Huafei <lihuaf...@huawei.com>
---
Changes in v3: 
 - As suggested by Christophe, replace kvzalloc() with kvcalloc()
 - Link to v2: 
https://lore.kernel.org/lkml/20241029101839.2605713-1-lihuaf...@huawei.com/

Changes in v2:
 - kvzalloc() call uses 'nps_info->v1.count' instead of '*range_cnt'
 - Link to v1: 
https://lore.kernel.org/lkml/20241028215933.2599271-1-lihuaf...@huawei.com/
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
index 4bd61c169ca8..620090f092ab 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
@@ -1757,11 +1757,13 @@ int amdgpu_discovery_get_nps_info(struct amdgpu_device 
*adev,
 
        switch (le16_to_cpu(nps_info->v1.header.version_major)) {
        case 1:
+               mem_ranges = kvcalloc(nps_info->v1.count,
+                                     sizeof(struct amdgpu_gmc_memrange),
+                                     GFP_KERNEL);
+               if (!mem_ranges)
+                       return -ENOMEM;
                *nps_type = nps_info->v1.nps_type;
                *range_cnt = nps_info->v1.count;
-               mem_ranges = kvzalloc(
-                       *range_cnt * sizeof(struct amdgpu_gmc_memrange),
-                       GFP_KERNEL);
                for (i = 0; i < *range_cnt; i++) {
                        mem_ranges[i].base_address =
                                nps_info->v1.instance_info[i].base_address;
-- 
2.25.1

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