linux-kernel - Re: [PATCH] kbuild: correct size calculation of bzImgae / fix x86 boot

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: <4B2FD252.4060700@msgid.tls.msk.ru>
Date:	Mon, 21 Dec 2009 22:53:54 +0300
From:	Michael Tokarev <mjt@....msk.ru>
To:	Michael Guntsche <mike@...loops.com>
CC:	Michal Marek <mmarek@...e.cz>, Sam Ravnborg <sam@...nborg.org>,
	Oliver Hartkopp <oliver@...tkopp.net>,
	linux-kernel <linux-kernel@...r.kernel.org>,
	Andreas Schwab <schwab@...ux-m68k.org>
Subject: Re: [PATCH] kbuild: correct size calculation of bzImgae / fix x86
 boot

Michael Guntsche wrote:
> On 21 Dec 09 15:17, Michal Marek wrote:
>>> How about moving this functionality to mkpiggy where we are
>>> less shell script dependent.
>>>
>>> Something like the following.
>>> I have only tested it lightly (vmlinux.bin did not differ
>>> before/after the patch.
>>
>> I think that it's a good idea to move this out of the makefiles. But for
>> 2.6.33, I think I prefer the patch from Andreas, provided he signs it
>> off and Michael G confirms that it fixes his issue.
> 
> Just a quick update from my side. I tried the patch from Andreas and build a kernel
> with dash as defaulti shell. I was able to boot the resulting kernel image
> without any problems.

That's not a good test case.  Because even with bogus data the kernel might
boot: for example, allocating alot more memory for the unpacking than necessary -
it does not crash but the data is still bogus.

The better (and much faster) check is to verify that the z_output_len value
in arch/x86/boot/compressed/piggy.S matches the size of
arch/x86/boot/compressed/vmlinuz.bin.

/mjt
--
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/