[PATCH v1 26/28] video: fbdev: uvesafb: Fix W=1 string related warnings

From: Sam Ravnborg <sam@ravnborg.org>
To: linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org,
	Lee Jones <lee.jones@linaro.org>
Cc: Aditya Pakki <pakki001@umn.edu>,
	Alexander Klimov <grandmaster@al2klimov.de>,
	Alex Dewar <alex.dewar90@gmail.com>,
	Antonino Daplas <adaplas@gmail.com>,
	Arnd Bergmann <arnd@arndb.de>,
	Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Daniel Vetter <daniel.vetter@ffwll.ch>,
	Evgeny Novikov <novikov@ispras.ru>,
	Ferenc Bakonyi <fero@drama.obuda.kando.hu>,
	Florian Tobias Schandinat <FlorianSchandinat@gmx.de>,
	George Kennedy <george.kennedy@oracle.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Gustavo Silva <gustavoars@kernel.org>,
	Jani Nikula <jani.nikula@intel.com>,
	Jason Yan <yanaijie@huawei.com>,
	Jingoo Han <jingoohan1@gmail.com>,
	Jiri Slaby <jirislaby@kernel.org>, Joe Perches <joe@perches.com>,
	Kristoffer Ericson <kristoffer.ericson@gmail.com>,
	Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	linux-nvidia@lists.surfsouth.com,
	Michal Januszewski <spock@gentoo.org>,
	Mike Rapoport <rppt@kernel.org>,
	Nathan Chancellor <natechancellor@gmail.com>,
	Peilin Ye <yepeilin.cs@gmail.com>, Peter Rosin <peda@axentia.se>,
	Qilong Zhang <zhangqilong3@huawei.com>,
	Randy Dunlap <rdunlap@infradead.org>,
	Saeed Mirzamohammadi <saeed.mirzamohammadi@oracle.com>,
	Sam Ravnborg <sam@ravnborg.org>,
	Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>,
	Thomas Winischhofer <thomas@winischhofer.net>,
	Thomas Zimemrmann <tzimmermann@suse.de>,
	Vaibhav Gupta <vaibhavgupta40@gmail.com>,
	Xiaofei Tan <tanxiaofei@huawei.com>
Subject: [PATCH v1 26/28] video: fbdev: uvesafb: Fix W=1 string related warnings
Date: Fri, 27 Nov 2020 20:58:23 +0100	[thread overview]
Message-ID: <20201127195825.858960-27-sam@ravnborg.org> (raw)
In-Reply-To: <20201127195825.858960-1-sam@ravnborg.org>

Two W=1 string related warnings.
- Using strncpy to copy string wihtout null-termination is not good.
  Use memcpy to copy only the relevant chars

- Fix a potential bug with a very long string, subtract one from the
  length to make room for the termination null.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Michal Januszewski <spock@gentoo.org>
Cc: linux-fbdev@vger.kernel.org
---
 drivers/video/fbdev/uvesafb.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/video/fbdev/uvesafb.c b/drivers/video/fbdev/uvesafb.c
index 8ee0fc9c63cf..45dc8da191e4 100644
--- a/drivers/video/fbdev/uvesafb.c
+++ b/drivers/video/fbdev/uvesafb.c
@@ -423,7 +423,7 @@ static int uvesafb_vbe_getinfo(struct uvesafb_ktask *task,
 	task->t.flags = TF_VBEIB;
 	task->t.buf_len = sizeof(struct vbe_ib);
 	task->buf = &par->vbe_ib;
-	strncpy(par->vbe_ib.vbe_signature, "VBE2", 4);
+	memcpy(par->vbe_ib.vbe_signature, "VBE2", 4);
 
 	err = uvesafb_exec(task);
 	if (err || (task->t.regs.eax & 0xffff) != 0x004f) {
@@ -1871,7 +1871,7 @@ static ssize_t v86d_show(struct device_driver *dev, char *buf)
 static ssize_t v86d_store(struct device_driver *dev, const char *buf,
 		size_t count)
 {
-	strncpy(v86d_path, buf, PATH_MAX);
+	strncpy(v86d_path, buf, PATH_MAX - 1);
 	return count;
 }
 static DRIVER_ATTR_RW(v86d);
-- 
2.27.0

