netdev - Re: [PATCH] ipv4: avoid undefined behavior in do_ip

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <50A12B46.4010805@gmail.com>
Date:	Mon, 12 Nov 2012 12:00:54 -0500
From:	Xi Wang <xi.wang@...il.com>
To:	David Laight <David.Laight@...LAB.COM>
CC:	David Miller <davem@...emloft.net>, netdev@...r.kernel.org
Subject: Re: [PATCH] ipv4: avoid undefined behavior in do_ip_setsockopt()

On 11/12/12 8:54 AM, David Laight wrote:
> 'All modern' is probably an overstatement, 'recent gcc' might be valid.

I agree if you consider gcc 3.4 released 8 years ago as "recent gcc",
or if you use a compiler other than gcc/clang/icc to compile the kernel.

> The 'switch' version will have an extra conditional to detect
> 'out of range' values - even though we know they can't happen.
> I'm not sure you can avoid that - even for an enum.

This out-of-range check is exactly what this patch wanted to add:
optname is a syscall parameter, and we should reject invalid optname
values before doing (1<<optname).

- xi
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html