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: <8f12147ee3cf4bbd8fc980821ae1deac@AcuMS.aculab.com>
Date: Fri, 22 Mar 2024 14:16:15 +0000
From: David Laight <David.Laight@...LAB.COM>
To: 'Russell King' <linux@...linux.org.uk>
CC: Ard Biesheuvel <ardb@...nel.org>, Jiangfeng Xiao
	<xiaojiangfeng@...wei.com>, "arnd@...db.de" <arnd@...db.de>,
	"keescook@...omium.org" <keescook@...omium.org>, "haibo.li@...iatek.com"
	<haibo.li@...iatek.com>, "angelogioacchino.delregno@...labora.com"
	<angelogioacchino.delregno@...labora.com>, "amergnat@...libre.com"
	<amergnat@...libre.com>, "akpm@...ux-foundation.org"
	<akpm@...ux-foundation.org>, "dave.hansen@...ux.intel.com"
	<dave.hansen@...ux.intel.com>, "douzhaolei@...wei.com"
	<douzhaolei@...wei.com>, "gustavoars@...nel.org" <gustavoars@...nel.org>,
	"jpoimboe@...nel.org" <jpoimboe@...nel.org>, "kepler.chenxin@...wei.com"
	<kepler.chenxin@...wei.com>, "kirill.shutemov@...ux.intel.com"
	<kirill.shutemov@...ux.intel.com>, "linux-hardening@...r.kernel.org"
	<linux-hardening@...r.kernel.org>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>, "linux-mm@...ck.org" <linux-mm@...ck.org>,
	"linux-arm-kernel@...ts.infradead.org"
	<linux-arm-kernel@...ts.infradead.org>, "nixiaoming@...wei.com"
	<nixiaoming@...wei.com>, "peterz@...radead.org" <peterz@...radead.org>,
	"wangbing6@...wei.com" <wangbing6@...wei.com>, "wangfangpeng1@...wei.com"
	<wangfangpeng1@...wei.com>, "jannh@...gle.com" <jannh@...gle.com>,
	"willy@...radead.org" <willy@...radead.org>
Subject: RE: [PATCH v2] ARM: unwind: improve unwinders for noreturn case

..
> Whereas we already provide an abort() function because iirc the
> compiler used to emit branches to that due to noreturn functions. If
> correct, there's previous convention for doing this - and abort() is
> still exists in the kernel and in userspace since it's part of ANSI
> C. This would be a more reliable and portable solution, but probably
> not for embedded platforms - and that's probably why it got removed.

Wouldn't you want it to do a 'bl abort' so that you could do a backtrace
to find out which 'noreturn' function had returned?

But that leaves you with another 'noreturn' function that you have
difficulty generating a backtrace from.

So you'd need a compiler option to specify what to put there.
I'd suspect linux would like something that generates an 'undefined
instruction' trap - since that would be expected to fault with the
saved PC pointing to the instruction itself (but architectures may vary).

'One size' definitely doesn't 'fit all' :-)

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ