From 7d7f8fe4e399519cc9ac68a475fec6d3a996341b Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Thu, 15 Sep 2022 17:11:44 +0300
Subject: [PATCH] remoteproc: Harden rproc_handle_vdev() against integer overflow
Git-commit: 7d7f8fe4e399519cc9ac68a475fec6d3a996341b
Patch-mainline: v6.1-rc1
References: git-fixes

The struct_size() macro protects against integer overflows but adding
"+ rsc->config_len" introduces the risk of integer overflows again.
Use size_add() to be safe.

Fixes: c87846571587 ("remoteproc: use struct_size() helper")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com>
Link: https://lore.kernel.org/r/YyMyoPoGOJUcEpZT@kili
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/remoteproc/remoteproc_core.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 6e8849f0df18..f5ba3b305aaf 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -520,12 +520,13 @@ static int rproc_handle_vdev(struct rproc *rproc, void *ptr,
 	struct fw_rsc_vdev *rsc = ptr;
 	struct device *dev = &rproc->dev;
 	struct rproc_vdev *rvdev;
+	size_t rsc_size;
 	int i, ret;
 	char name[16];
 
 	/* make sure resource isn't truncated */
-	if (struct_size(rsc, vring, rsc->num_of_vrings) + rsc->config_len >
-			avail) {
+	rsc_size = struct_size(rsc, vring, rsc->num_of_vrings);
+	if (size_add(rsc_size, rsc->config_len) > avail) {
 		dev_err(dev, "vdev rsc is truncated\n");
 		return -EINVAL;
 	}
-- 
2.35.3