linux-kernel - Re: [RFC PATCH] kernel/signal.c: avoid BUG

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

Message-ID: <20130529173634.GA2020@redhat.com>
Date:	Wed, 29 May 2013 19:36:34 +0200
From:	Oleg Nesterov <oleg@...hat.com>
To:	David Daney <ddaney.cavm@...il.com>
Cc:	James Hogan <james.hogan@...tec.com>, linux-kernel@...r.kernel.org,
	linux-mips@...ux-mips.org, Ralf Baechle <ralf@...ux-mips.org>,
	Al Viro <viro@...iv.linux.org.uk>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Kees Cook <keescook@...omium.org>
Subject: Re: [RFC PATCH] kernel/signal.c: avoid BUG_ON with SIG128 (MIPS)

On 05/29, David Daney wrote:
>
> On 05/29/2013 10:01 AM, James Hogan wrote:
>> MIPS has 128 signals, the highest of which has the number 128. The
>
> I wonder if we should change the ABI and reduce the number of signals to
> 127 instead of this patch.

Same thoughts...

>> @@ -2366,8 +2366,12 @@ relock:
>>
>>   		/*
>>   		 * Death signals, no core dump.
>> +		 *
>> +		 * MIPS has a signal number 128 which clashes with the core dump
>> +		 * bit. If this was the signal we still want to report a valid
>> +		 * exit code, so round it down to 127.
>>   		 */
>> -		do_group_exit(info->si_signo);
>> +		do_group_exit(min(info->si_signo, 127));

This avoids BUG_ON() but obviously fools WIFSIGNALED(), doesn't look
very nice.

Oleg.

--
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/