1 From: Vasiliy Kulikov <segoon@openwall.com>
2 Subject: Re: [PATCH] core: dev: don't call BUG() on bad input
3 Date: Mon, 14 Feb 2011 15:23:13 +0300
5 Message-ID: <20110214122313.GA10062@albatros>
6 References: <1297680967-11893-1-git-send-email-segoon@openwall.com>
7 <4D591D04.4050000@gmail.com>
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11 Cc: linux-kernel@vger.kernel.org,
12 "David S. Miller" <davem@davemloft.net>,
13 Eric Dumazet <eric.dumazet@gmail.com>,
14 Tom Herbert <therbert@google.com>,
15 Changli Gao <xiaosuo@gmail.com>,
16 Jesse Gross <jesse@nicira.com>, netdev@vger.kernel.org
17 To: Nicolas de =?iso-8859-1?Q?Peslo=FCan?=
18 <nicolas.2p.debian@gmail.com>
19 X-From: netdev-owner@vger.kernel.org Mon Feb 14 13:24:40 2011
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70 On Mon, Feb 14, 2011 at 13:16 +0100, Nicolas de Peslo=FCan wrote:
71 > >- BUG_ON(strlen(name)>=3D sizeof(dev->name));
72 > >+ if (strnlen(name, sizeof(dev->name))>=3D sizeof(dev->name)) {
74 Ehh... Space after ")" is needed :)
76 > "size_t strnlen(const char *s, size_t maxlen) : The strnlen()
77 > function returns strlen(s), if that is less than maxlen, or maxlen
78 > if there is no '\0' character among the first maxlen characters
81 > How can strnlen(name, sizeof(dev->name)) be greater than sizeof(dev->=
84 > Shouldn't it be "if (strnlen(name, sizeof(dev->name)) =3D=3D sizeof(d=
87 Not a big deal, but MO it's better to guard from everything that
88 is not a good input by negating the check. strnlen() < sizeof() is OK,
89 strnlen() >=3D sizeof() is bad. Is "=3D=3D" more preferable for net/ c=
95 http://www.openwall.com - bringing security into open computing environ=
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