From mboxrd@z Thu Jan 1 00:00:00 1970 From: SF Markus Elfring Subject: [PATCH 1/2] tun: Use memdup_user() rather than duplicating its implementation Date: Sat, 20 Aug 2016 09:34:56 +0200 Message-ID: References: <566ABCD9.1060404@users.sourceforge.net> <9cf06275-924d-6c22-d8a8-f733a03cca23@users.sourceforge.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: LKML , kernel-janitors@vger.kernel.org, Julia Lawall To: netdev@vger.kernel.org, "David S. Miller" , Eric Dumazet , Jason Wang , "Michael S. Tsirkin" , Mike Rapoport , Paolo Abeni , Soheil Hassas Yeganeh Return-path: In-Reply-To: <9cf06275-924d-6c22-d8a8-f733a03cca23@users.sourceforge.net> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Markus Elfring Date: Sat, 20 Aug 2016 08:54:15 +0200 Reuse existing functionality from memdup_user() instead of keeping duplicate source code. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring --- drivers/net/tun.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 9c8b5bc..a1aeccb 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -731,14 +731,9 @@ static int update_filter(struct tap_filter *filter, void __user *arg) } alen = ETH_ALEN * uf.count; - addr = kmalloc(alen, GFP_KERNEL); - if (!addr) - return -ENOMEM; - - if (copy_from_user(addr, arg + sizeof(uf), alen)) { - err = -EFAULT; - goto done; - } + addr = memdup_user(arg + sizeof(uf), alen); + if (IS_ERR(addr)) + return PTR_ERR(addr); /* The filter is updated without holding any locks. Which is * perfectly safe. We disable it first and in the worst -- 2.9.3