In the SDSP probe path, qcom_scm_assign_mem() is used to assign the
reserved memory to the configured VMIDs, but its return value was not checked.

Fail the probe if the SCM call fails to avoid continuing with an
unexpected/incorrect memory permission configuration.

This issue was found by an in-house analysis workflow that extracts AST-based
information and runs static checks, with LLM assistance for triage, and was
confirmed by manual code review.
No hardware testing was performed.

Fixes: c3c0363bc72d4 ("misc: fastrpc: support complete DMA pool access to the DSP")
Cc: stable@vger.kernel.org # 6.11-rc1
Signed-off-by: Xingjing Deng <xjdeng@buaa.edu.cn>
---
v8:
- Remove the redundant brace.
- Link to v7: https://lore.kernel.org/linux-arm-msm/20260129233703.407404-1-xjdeng@buaa.edu.cn/

v7:
- Add the detail description of how the tool detect.
- Link to v6: https://lore.kernel.org/linux-arm-msm/20260128033454.2614886-1-xjdeng@buaa.edu.cn/

v6:
- Add description of the detection tool.
- Link to v5: https://lore.kernel.org/linux-arm-msm/20260117140351.875511-1-xjdeng@buaa.edu.cn/T/#u

v5:
- Squash the functional change and indentation fix into a single patch.
- Link to v4: https://lore.kernel.org/linux-arm-msm/2026011637-statute-showy-2c3f@gregkh/T/#t

v4:
- Format the indentation
- Link to v3: https://lore.kernel.org/linux-arm-msm/20260113084352.72itrloj5w7qb5o3@hu-mojha-hyd.qualcomm.com/T/#t

v3:
- Add missing linux-kernel@vger.kernel.org to cc list.
- Standarlize changelog placement/format.
- Link to v2: https://lore.kernel.org/linux-arm-msm/20260113063618.e2ke47gy3hnfi67e@hu-mojha-hyd.qualcomm.com/T/#t

v2:
- Add Fixes: and Cc: stable tags.
- Link to v1: https://lore.kernel.org/linux-arm-msm/20260113022550.4029635-1-xjdeng@buaa.edu.cn/T/#u
---
 drivers/misc/fastrpc.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
index ee652ef01534..a669e4b2bb35 100644
--- a/drivers/misc/fastrpc.c
+++ b/drivers/misc/fastrpc.c
@@ -2337,8 +2337,10 @@ static int fastrpc_rpmsg_probe(struct rpmsg_device *rpdev)
 		if (!err) {
 			src_perms = BIT(QCOM_SCM_VMID_HLOS);
 
-			qcom_scm_assign_mem(res.start, resource_size(&res), &src_perms,
+			err = qcom_scm_assign_mem(res.start, resource_size(&res), &src_perms,
 				    data->vmperms, data->vmcount);
+			if (err)
+				goto err_free_data;
 		}
 
 	}
-- 
2.25.1

On Sat, Jan 31, 2026 at 02:55:39PM +0800, Xingjing Deng wrote:
> In the SDSP probe path, qcom_scm_assign_mem() is used to assign the
> reserved memory to the configured VMIDs, but its return value was not checked.
> 
> Fail the probe if the SCM call fails to avoid continuing with an
> unexpected/incorrect memory permission configuration.
> 
> This issue was found by an in-house analysis workflow that extracts AST-based
> information and runs static checks, with LLM assistance for triage, and was
> confirmed by manual code review.
> No hardware testing was performed.
> 
> Fixes: c3c0363bc72d4 ("misc: fastrpc: support complete DMA pool access to the DSP")
> Cc: stable@vger.kernel.org # 6.11-rc1
> Signed-off-by: Xingjing Deng <xjdeng@buaa.edu.cn>
> ---
> v8:
> - Remove the redundant brace.
> - Link to v7: https://lore.kernel.org/linux-arm-msm/20260129233703.407404-1-xjdeng@buaa.edu.cn/
> 

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>


-- 
With best wishes
Dmitry