[PATCH 6.12.y] misc: fastrpc: check qcom_scm_assign_mem() return in rpmsg_probe

[Sasha Levin <sashal@kernel.org>]

From: Xingjing Deng <micro6947@gmail.com>

[ Upstream commit 6a502776f4a4f80fb839b22f12aeaf0267fca344 ]

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>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://patch.msgid.link/20260131065539.2124047-1-xjdeng@buaa.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ adapted qcom_scm_assign_mem() error check to use fdev_error label and rmem-based memory API ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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 d6c55c338b062..d3d4d50fb0e54 100644
--- a/drivers/misc/fastrpc.c
+++ b/drivers/misc/fastrpc.c
@@ -2345,8 +2345,10 @@ static int fastrpc_rpmsg_probe(struct rpmsg_device *rpdev)
 
 		src_perms = BIT(QCOM_SCM_VMID_HLOS);
 
-		qcom_scm_assign_mem(rmem->base, rmem->size, &src_perms,
+		err = qcom_scm_assign_mem(rmem->base, rmem->size, &src_perms,
 				    data->vmperms, data->vmcount);
+		if (err)
+			goto fdev_error;
 
 	}
 
-- 
2.53.0