netdev - Re: [PATCH net] mptcp: avoid NULL-ptr derefence on fallback

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-Id: <20200526.201859.755046542854273149.davem@davemloft.net>
Date:   Tue, 26 May 2020 20:18:59 -0700 (PDT)
From:   David Miller <davem@...emloft.net>
To:     pabeni@...hat.com
Cc:     netdev@...r.kernel.org, mathew.j.martineau@...ux.intel.com,
        kuba@...nel.org, mptcp@...ts.01.org,
        syzkaller-bugs@...glegroups.com
Subject: Re: [PATCH net] mptcp: avoid NULL-ptr derefence on fallback

From: Paolo Abeni <pabeni@...hat.com>
Date: Mon, 25 May 2020 16:38:47 +0200

> In the MPTCP receive path we must cope with TCP fallback
> on blocking recvmsg(). Currently in such code path we detect
> the fallback condition, but we don't fetch the struct socket
> required for fallback.
> 
> The above allowed syzkaller to trigger a NULL pointer
> dereference:
 ...
> Address the issue initializing the struct socket reference
> before entering the fallback code.
> 
> Reported-and-tested-by: syzbot+c6bfc3db991edc918432@...kaller.appspotmail.com
> Suggested-by: Ondrej Mosnacek <omosnace@...hat.com>
> Fixes: 8ab183deb26a ("mptcp: cope with later TCP fallback")
> Signed-off-by: Paolo Abeni <pabeni@...hat.com>

Applied and queued up for -stable, thanks.