linux-kernel - Re: [RFC] ptrace: add generic SET

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: <OF152076B7.38277C08-ONC1257D8F.0050C2DF-C1257D8F.00516BF2@de.ibm.com>
Date:	Thu, 13 Nov 2014 15:49:20 +0100
From:	Ulrich Weigand <Ulrich.Weigand@...ibm.com>
To:	Arnd Bergmann <arnd@...db.de>
Cc:	Andreas Krebbel1 <Andreas.Krebbel@...ibm.com>,
	"keescook@...omium.org" <keescook@...omium.org>,
	linaro-kernel@...ts.linaro.org,
	"linux@....linux.org.uk" <linux@....linux.org.uk>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Oleg Nesterov <oleg@...hat.com>,
	"roland@...k.frob.com" <roland@...k.frob.com>,
	AKASHI Takahiro <takahiro.akashi@...aro.org>
Subject: Re: [RFC] ptrace: add generic SET_SYSCALL request

Arnd Bergmann <arnd@...db.de> wrote on 13.11.2014 11:21:28:

> I have to admit that I don't really understand gdb internals, but from
> a first look I get the impression that it will just do the right thing
> if you reuse NT_S390_SYSTEM_CALL on ARM64 with the same semantics.

There's an interface between BFD and GDB proper involved here.  BFD will
detect the presence of register set notes in the core dump, and will
translate them into virtual sections; GDB will then simply look up such
sections under well-known names.

In particular, the NT_S390_SYSTEM_CALL note will be translated by BFD
into a virtual section named ".reg-s390-system-call"; GDB platform-
specific code will look for sections of this particular name.

So if you were to create notes using the same note type, by default it
would do nothing on ARM64.  You might add code to the ARM64 back-end
to also look for a section ".reg-s390-system-call", but that would be
somewhat confusing.  Using a new, platform-specific note type for ARM64
would appear to fit better with existing precedent.

Bye,
Ulrich

--
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/