From: Florian Weimer <fweimer@redhat.com>
To: Rich Felker <dalias@libc.org>
Cc: Trevor Gross <tg@trevorgross.com>,
musl@lists.openwall.com, linux-man@vger.kernel.org,
libc-alpha@sourceware.org
Subject: Re: [musl] Re: async-signal-safety of chroot
Date: Thu, 24 Sep 2026 11:21:50 +0200 [thread overview]
Message-ID: <lhuecejhump.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <20260924021222.GC23438@brightrain.aerifal.cx> (Rich Felker's message of "Wed, 23 Sep 2026 22:12:22 -0400")
* Rich Felker:
> musl makes clone roughly as safe as fork (see commit fa4a8abd06a4),
> and disallows flags that are not compatible with executing any part of
> libc in the child, but afaik glibc still has an anything-goes
> approach.
Yes, there is no filtering in glibc, and no update of the (shared) TCB.
Several web browsers longjmp out of the clone callback and patch the TCB
with the new TID, so that mutexes work as expected.
Thanks,
Florian
next prev parent reply other threads:[~2026-09-24 9:22 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-23 0:53 async-signal-safety of chroot tg
2026-09-23 1:34 ` [musl] " Rich Felker
2026-09-23 4:17 ` John Scott
2026-09-23 4:40 ` [musl] " Rich Felker
2026-09-23 8:38 ` Florian Weimer
2026-09-23 23:21 ` Trevor Gross
2026-09-24 0:34 ` Trevor Gross
2026-09-24 2:12 ` [musl] " Rich Felker
2026-09-24 9:21 ` Florian Weimer [this message]
2026-09-23 23:38 ` [PATCH 1/2] man/man2/chroot.2: Document that chroot is AS-safe Trevor Gross
2026-09-23 23:38 ` [PATCH 2/2] man/man2/fork.2: Document glibc and musl relaxed fork->exec AS requirements Trevor Gross
2026-09-23 23:47 ` [musl] " Rich Felker
2026-09-25 19:54 ` Florian Weimer
2026-10-02 6:50 ` Trevor Gross
2026-10-03 20:48 ` Gabriel Ravier
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