linux-kernel - Re: [patch] x86: ptrace and core-dump extensions for xstate

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: <20100205211515.9805FE7@magilla.sf.frob.com>
Date:	Fri,  5 Feb 2010 13:15:15 -0800 (PST)
From:	Roland McGrath <roland@...hat.com>
To:	"H. Peter Anvin" <hpa@...or.com>
Cc:	Suresh Siddha <suresh.b.siddha@...el.com>,
	Oleg Nesterov <oleg@...hat.com>, Ingo Molnar <mingo@...e.hu>,
	Thomas Gleixner <tglx@...utronix.de>,
	LKML <linux-kernel@...r.kernel.org>,
	"Lu, Hongjiu" <hongjiu.lu@...el.com>,
	"Lachner, Peter" <peter.lachner@...el.com>
Subject: Re: [patch] x86: ptrace and core-dump extensions for xstate

> #define PTRACE_GETREGS(r) (((r) << 16) | PTRACE_GETREGS_CMD)
> 
> ... or something like that?

(You can't use that exact name, it's taken.)  IMHO this is some spurious
obfuscation that is not warranted by saving the two get_user calls in the
kernel.  (OTOH, my suggestion requires a whole extra 5 lines of code or so
in compat_sys_ptrace because the indirection in the ABI is sensitive to
userland word size.)  But I don't feel strongly about the particulars of
the ptrace API addition, just that it be generic to cover any regset and
not be prone to implicit buffer-size miscommunications.  I'll leave it to
whatever Oleg wants to implement.

Thanks,
Roland
--
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/