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From: Florian Weimer via Libc-alpha <libc-alpha@sourceware.org>
To: "H.J. Lu via Libc-alpha" <libc-alpha@sourceware.org>
Subject: Re: [PATCH] x86/CET: Update vfork to prevent child return
Date: Wed, 14 Oct 2020 15:43:18 +0200	[thread overview]
Message-ID: <87wnzsord5.fsf@oldenburg2.str.redhat.com> (raw)
In-Reply-To: <20201013175146.58558-1-hjl.tools@gmail.com> (H. J. Lu via Libc-alpha's message of "Tue, 13 Oct 2020 10:51:46 -0700")

* H. J. Lu via Libc-alpha:

> Child of vfork should either call _exit or one of the exec family of
> functions.  But normally there is nothing to prevent child of vfork from
> return of the vfork-calling function.  Simpilfy x86 vfork when shadow
> stack is in use to introduce mismatched shadow stack in child of vfork
> to trigger SIGSEGV when the child returns from the function in which
> vfork was called.

Looks reasonable to me, thanks.  We'll see what breaks as a result of
this. 8-/ But everything that runs into crash will already have weird
bugs.

Thanks,
Florian
-- 
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  parent reply	other threads:[~2020-10-14 13:43 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-13 17:51 [PATCH] x86/CET: Update vfork to prevent child return H.J. Lu via Libc-alpha
2020-10-14 13:30 ` H.J. Lu via Libc-alpha
2020-10-14 13:43 ` Florian Weimer via Libc-alpha [this message]
  -- strict thread matches above, loose matches on Subject: below --
2020-09-16 23:45 H.J. Lu via Libc-alpha
2020-09-17  0:46 ` Florian Weimer
2020-09-17 12:40   ` H.J. Lu via Libc-alpha

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