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From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Antonino Daplas <adaplas@gmail.com>,
        linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org,
        Tim Gardner <tim.gardner@canonical.com>,
        Helge Deller <deller@gmx.de>, Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.16 0816/1017] video: fbdev: nvidiafb: Use strscpy() to prevent buffer overflow
Date:   Tue,  5 Apr 2022 09:28:49 +0200
Message-Id: <20220405070418.471174787@linuxfoundation.org>
In-Reply-To: <20220405070354.155796697@linuxfoundation.org>
References: <20220405070354.155796697@linuxfoundation.org>
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From: Tim Gardner <tim.gardner@canonical.com>

[ Upstream commit 37a1a2e6eeeb101285cd34e12e48a881524701aa ]

Coverity complains of a possible buffer overflow. However,
given the 'static' scope of nvidia_setup_i2c_bus() it looks
like that can't happen after examiniing the call sites.

CID 19036 (#1 of 1): Copy into fixed size buffer (STRING_OVERFLOW)
1. fixed_size_dest: You might overrun the 48-character fixed-size string
  chan->adapter.name by copying name without checking the length.
2. parameter_as_source: Note: This defect has an elevated risk because the
  source argument is a parameter of the current function.
 89        strcpy(chan->adapter.name, name);

Fix this warning by using strscpy() which will silence the warning and
prevent any future buffer overflows should the names used to identify the
channel become much longer.

Cc: Antonino Daplas <adaplas@gmail.com>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/video/fbdev/nvidia/nv_i2c.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/video/fbdev/nvidia/nv_i2c.c b/drivers/video/fbdev/nvidia/nv_i2c.c
index d7994a173245..0b48965a6420 100644
--- a/drivers/video/fbdev/nvidia/nv_i2c.c
+++ b/drivers/video/fbdev/nvidia/nv_i2c.c
@@ -86,7 +86,7 @@ static int nvidia_setup_i2c_bus(struct nvidia_i2c_chan *chan, const char *name,
 {
 	int rc;
 
-	strcpy(chan->adapter.name, name);
+	strscpy(chan->adapter.name, name, sizeof(chan->adapter.name));
 	chan->adapter.owner = THIS_MODULE;
 	chan->adapter.class = i2c_class;
 	chan->adapter.algo_data = &chan->algo;
-- 
2.34.1