2021-12-17 02:21:59

by Jiasheng Jiang

[permalink] [raw]
Subject: [PATCH] drm/amdgpu: potential dereference of null pointer

The return value of dma_alloc_coherent() needs to be checked.
To avoid use of null pointer in memcpy_toio() in case of the failure of
alloc.

Fixes: 57430471e2fa ("drm/amdgpu: Add support for USBC PD FW download")
Signed-off-by: Jiasheng Jiang <[email protected]>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c
index a09483beb968..613e25bf87e5 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c
@@ -3034,6 +3034,10 @@ static ssize_t psp_usbc_pd_fw_sysfs_write(struct device *dev,

/* We need contiguous physical mem to place the FW for psp to access */
cpu_addr = dma_alloc_coherent(adev->dev, usbc_pd_fw->size, &dma_addr, GFP_KERNEL);
+ if (!cpu_addr) {
+ ret = -ENOMEM;
+ goto rel_buf;
+ }

ret = dma_mapping_error(adev->dev, dma_addr);
if (ret)
--
2.25.1