From 77d5f0295ea1c5a3f6d30ba97dc6ce65f2dec546 Mon Sep 17 00:00:00 2001
From: Surbhi Singh <surbhis@nvidia.com>
Date: Mon, 16 Dec 2024 06:49:46 +0000
Subject: [PATCH] video: tegra: nvmap:  Fix INT30-C overflow defect

Add check for subtraction overflow using BUG_ON.

JIRA: TMM-5724
Bug 4479044

Change-Id: If4b63979c207d6246ea4c8a3fffa5f89032956ba
Signed-off-by: Surbhi Singh <surbhis@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nv-oot/+/3268715
Reviewed-by: Ketan Patil <ketanp@nvidia.com>
Reviewed-by: Sachin Nikam <snikam@nvidia.com>
GVS: buildbot_gerritrpt <buildbot_gerritrpt@nvidia.com>
---
 drivers/video/tegra/nvmap/nvmap_pp.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/video/tegra/nvmap/nvmap_pp.c b/drivers/video/tegra/nvmap/nvmap_pp.c
index b2360760..027c9ffa 100644
--- a/drivers/video/tegra/nvmap/nvmap_pp.c
+++ b/drivers/video/tegra/nvmap/nvmap_pp.c
@@ -79,6 +79,7 @@ static bool nvmap_is_big_page(struct nvmap_page_pool *pool,
 	if (pool->pages_per_big_pg <= 1)
 		return false;
 
+	BUG_ON(nr < idx);
 	if (nr - idx < pool->pages_per_big_pg)
 		return false;