From: Thomas Gleixner <tglx@linutronix.de>
To: Paolo Bonzini <pbonzini@redhat.com>,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: syzbot+00be5da1d75f1cc95f6b@syzkaller.appspotmail.com,
Sean Christopherson <sean.j.christopherson@intel.com>
Subject: Re: [PATCH] KVM: x86: remove bogus user-triggerable WARN_ON
Date: Fri, 20 Mar 2020 16:22:50 +0100 [thread overview]
Message-ID: <87o8sr59v9.fsf@nanos.tec.linutronix.de> (raw)
In-Reply-To: <20200319174318.20752-1-pbonzini@redhat.com>
Paolo Bonzini <pbonzini@redhat.com> writes:
> The WARN_ON is essentially comparing a user-provided value with 0. It is
> trivial to trigger it just by passing garbage to KVM_SET_CLOCK. Guests
> can break if you do so, but if it hurts when you do like this just do not
> do it.
Yes, it's a user provided value and it's completely unchecked. If that
value is bogus then the guest will go sideways because timekeeping is
completely busted. At least you should explain WHY you don't care.
Thanks,
tglx
next prev parent reply other threads:[~2020-03-20 15:23 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-19 17:43 [PATCH] KVM: x86: remove bogus user-triggerable WARN_ON Paolo Bonzini
2020-03-19 17:52 ` Sean Christopherson
2020-03-20 15:22 ` Thomas Gleixner [this message]
2020-03-20 15:23 ` Thomas Gleixner
2020-03-20 17:47 ` Paolo Bonzini
2020-03-20 18:18 ` Thomas Gleixner
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=87o8sr59v9.fsf@nanos.tec.linutronix.de \
--to=tglx@linutronix.de \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pbonzini@redhat.com \
--cc=sean.j.christopherson@intel.com \
--cc=syzbot+00be5da1d75f1cc95f6b@syzkaller.appspotmail.com \
/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;
as well as URLs for NNTP newsgroup(s).