linux-kernel - Re: [PATCH] x86_32: Fix module version table mismatch.

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 for Android: free password hash cracker in your pocket

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

Date:	Tue, 23 Apr 2013 18:00:44 -0700
From:	"H. Peter Anvin" <hpa@...or.com>
To:	Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>
CC:	arjan@...radead.org, james.hogan@...tec.com, rusty@...tcorp.com.au,
	linux-kernel@...r.kernel.org, andy.shevchenko@...il.com
Subject: Re: [PATCH] x86_32: Fix module version table mismatch.

On 04/23/2013 05:52 PM, H. Peter Anvin wrote:
> On 04/23/2013 05:40 AM, Tetsuo Handa wrote:
>> Commit a4b6a77b "module: fix symbol versioning with symbol prefixes" broke
>> loading of net/ipv6/ipv6.ko built with CONFIG_MODVERSIONS=y for x86_32.
> 
> This really does seem to be the offending commit, although I'm still
> confused how the heck that is possible.
> 

OK, now I grok.

The bug is the use of VMLINUX_SYMBOL_STR(%s) which expands at the time
the output of modpost is compiled.  However, VMLINUX_SYMBOL_STR() unlike
__VMLINUX_SYMBOL_STR() does macro expansion on its argument, which is
actively wrong here.

I think the choice is either to change this to __VMLINUX_SYMBOL_STR() or
re-introduce CONFIG_SYMBOL_PREFIX (or its equivalent) so that modprobe
can emit it at compile time (assuming there even should *be* a prefix on
the symbol here, i.e. that the compiler won't add it.)

Either way -- James, Rusty, this is in your court.

	-hpa

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/