lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-ID: <CANn89iLPLu=cP0zu5r+hsXudSjMzieWke=nh0YwccH1QJUnzog@mail.gmail.com> Date: Thu, 1 Sep 2022 13:54:22 -0700 From: Eric Dumazet <edumazet@...gle.com> To: Jakub Kicinski <kuba@...nel.org> Cc: Kees Cook <keescook@...omium.org>, "David S. Miller" <davem@...emloft.net>, Paolo Abeni <pabeni@...hat.com>, Pablo Neira Ayuso <pablo@...filter.org>, Jozsef Kadlecsik <kadlec@...filter.org>, Florian Westphal <fw@...len.de>, syzbot <syzkaller@...glegroups.com>, Yajun Deng <yajun.deng@...ux.dev>, netdev <netdev@...r.kernel.org>, netfilter-devel@...r.kernel.org, coreteam@...filter.org, Oliver Hartkopp <socketcan@...tkopp.net>, Harshit Mogalapalli <harshit.m.mogalapalli@...cle.com>, LKML <linux-kernel@...r.kernel.org>, linux-hardening@...r.kernel.org Subject: Re: [PATCH 1/2] netlink: Bounds-check nlmsg_len() On Thu, Sep 1, 2022 at 12:49 PM Jakub Kicinski <kuba@...nel.org> wrote: > > On Wed, 31 Aug 2022 23:27:08 -0700 Kees Cook wrote: > > This would catch corrupted values... > > > > Is the concern the growth in image size? The check_sub_overflow() isn't > > large at all -- it's just adding a single overflow bit test. The WARNs > > are heavier, but they're all out-of-line. > > It turns the most obvious function into a noodle bar :( > > Looking at this function in particular is quite useful, because > it clearly indicates that the nlmsg_len includes the header. > > How about we throw in a > > WARN_ON_ONCE(nlh->nlmsg_len < NLMSG_HDRLEN || > nlh->nlmsg_len > INT_MAX); > > but leave the actual calculation human readable C? This is inlined, and will add a lot of extra code. We are making the kernel slower at each release. What about letting fuzzers like syzbot find the potential issues ? DEBUG_NET_WARN_ON_ONCE(...);
Powered by blists - more mailing lists