linux-kernel - Re: [PATCH] alternative to sys

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]

Date:	Thu, 24 Apr 2008 17:05:45 +0200
From:	"Michael Kerrisk" <michael.kerrisk@...glemail.com>
To:	"Ulrich Drepper" <drepper@...hat.com>
Cc:	"Michael Kerrisk" <mtk.manpages@...il.com>,
	"Alan Cox" <alan@...rguk.ukuu.org.uk>,
	linux-kernel@...r.kernel.org, netdev@...r.kernel.org,
	akpm@...ux-foundation.org,
	"Linus Torvalds" <torvalds@...ux-foundation.org>,
	michael.kerrisk@...il.com, linux-man@...r.kernel.org
Subject: Re: [PATCH] alternative to sys_indirect, part 1

On Thu, Apr 24, 2008 at 4:49 PM, Ulrich Drepper <drepper@...hat.com> wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
>  Hash: SHA1
>
>
>  Michael Kerrisk wrote:
>  > * dup2() -- use fcntl(F_DUPFD) instead
>
>  Wrong.  You cannot implement dup2 with fcntl since the latter won't use
>  a file descriptor which is already in use.

True.  One could add a flag to fcntl() to provide that behavior.

>  > So the alternative to sys_indirect(), at least for the purpose of
>  > O_CLOEXEC and similar, would be to create 5 new system calls (or six,
>  > if one finds the signalfd() hack too ugly, which perhaps it is; or 7
>  > if one doesn't like Alan's suggestion for socket()
>
>  Without changing the socket interfaces (plural, socketpair) there would

Yes, I overlooked socket pair()...

>  have to be 7 new syscalls, with changing socket* to an IMO cleaner
>  interface 9.
>
>
>  Or we just add sys_indirect (which is also usable for other syscall
>  extensions, not just the CLOEXEC stuff) and let userlevel (i.e., me)
>  worry about adding new interfaces to libc.  As you can see, for the more
>  recent interfaces like signalfd I have already added an additional
>  parameter so the number of interface changes would be reduced.
>
>  Somebody please make a call and then let's go on with life.  I don't
>  care much either way anymore.  I do hope nobody thinks this is an issue
>  which can be completely ignored (see, e.g., the bug I pointed to the
>  other day).

Since I had to go search, here it is again
http://bugzilla.redhat.com/show_bug.cgi?id=443321
--
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/