mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Alejandro Colomar <alx.manpages@gmail.com>
To: Florian Weimer <fweimer@redhat.com>
Cc: "Christian Brauner" <brauner@kernel.org>,
	"Michael Kerrisk" <mtk.manpages@gmail.com>,
	linux-kernel@vger.kernel.org,
	"Коренберг Марк" <socketpair@gmail.com>,
	"Andrei Vagin" <avagin@openvz.org>,
	"Dmitry Safonov" <dima@arista.com>,
	"Thomas Gleixner" <tglx@linutronix.de>,
	"Arnd Bergmann" <arnd@arndb.de>,
	"Serge Hallyn" <serge@hallyn.com>,
	linux-api@vger.kernel.org, bugzilla-daemon@kernel.org
Subject: Re: [Bug 215813] syscall(SYS_vfork) causes execve() to return 0. (was: vfork(2) behavior not consistent with fork(2))
Date: Wed, 6 Apr 2022 21:31:57 +0200	[thread overview]
Message-ID: <5e3946e1-f4bb-e3f8-11e9-be26589972b6@gmail.com> (raw)
In-Reply-To: <87k0c2qagv.fsf@oldenburg.str.redhat.com>

Hi Florian,

On 4/6/22 21:26, Florian Weimer wrote:
> It's not clear if this is valid.  The syscall function in glibc does not
> protect the on-stack return address against overwriting, so it can't be
> used to call SYS_vfork on x86.
> 
> Can you reproduce this with a true inline syscall, or the glibc vfork
> function (which protects the return address)?

If you tell me how I can call a syscall without the libc wrapper or 
syscall(2), sure, I can try :)

If syscall(2) can't be used for certain syscalls, maybe we should 
document that.

Thanks,

Alex

      reply	other threads:[~2022-04-06 21:03 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-215769-216477@https.bugzilla.kernel.org/>
     [not found] ` <bug-215769-216477-to2O9X1Knw@https.bugzilla.kernel.org/>
2022-04-02 21:15   ` vfork(2) fails after unshare(CLONE_NEWTIME) (was: [Bug 215769] man 2 vfork() does not document corner case when PID == 1) Alejandro Colomar (man-pages)
2022-04-04  8:05     ` Christian Brauner
2022-04-05 19:28       ` vfork(2) behavior not consistent with fork(2) (was: vfork(2) fails after unshare(CLONE_NEWTIME) (was: [Bug 215769] man 2 vfork() does not document corner case when PID == 1)) Alejandro Colomar
2022-04-06  8:46         ` Christian Brauner
2022-04-06 19:22           ` Alejandro Colomar
2022-04-06 19:26             ` vfork(2) behavior not consistent with fork(2) Florian Weimer
2022-04-06 19:31               ` Alejandro Colomar [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=5e3946e1-f4bb-e3f8-11e9-be26589972b6@gmail.com \
    --to=alx.manpages@gmail.com \
    --cc=arnd@arndb.de \
    --cc=avagin@openvz.org \
    --cc=brauner@kernel.org \
    --cc=bugzilla-daemon@kernel.org \
    --cc=dima@arista.com \
    --cc=fweimer@redhat.com \
    --cc=linux-api@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mtk.manpages@gmail.com \
    --cc=serge@hallyn.com \
    --cc=socketpair@gmail.com \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®