From: Demi Marie Obenour <demiobenour@gmail.com>
To: Xen developer discussion <xen-devel@lists.xenproject.org>
Subject: Undefined behavior in libxenvchan
Date: Sun, 14 Dec 2025 14:09:15 -0500 [thread overview]
Message-ID: <e06eb432-289b-447a-8c3d-43da4705b4e9@gmail.com> (raw)
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I noticed that libxenvchan has undefined behavior: it passes pointers
to guest memory to memcpy() even though they can be concurrently
changed.
Would it make sense to reuse some of Xen's copy_from_guest() code
instead? There might be a licensing problem (GPL vs LGPL), though.
I think the only approach that isn't UB and has decent performance
is to do the whole copy in assembly.
--
Sincerely,
Demi Marie Obenour (she/her/hers)
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next reply other threads:[~2025-12-14 19:09 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-12-14 19:09 Demi Marie Obenour [this message]
2025-12-14 22:50 ` Undefined behavior in libxenvchan Andrew Cooper
2025-12-14 23:08 ` Demi Marie Obenour
2025-12-15 9:41 ` Jan Beulich
2025-12-15 11:10 ` Teddy Astie
2025-12-15 18:17 ` Demi Marie Obenour
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