netdev - Re: [PATCH 1/2] bluetooth: hci_ldisc: fix NULL-pointer dereference on tty

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 for Android: free password hash cracker in your pocket

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

Message-ID: <1331228722.14217.7.camel@aeonflux>
Date:	Thu, 08 Mar 2012 09:45:22 -0800
From:	Marcel Holtmann <marcel@...tmann.org>
To:	Johan Hovold <jhovold@...il.com>
Cc:	"Gustavo F. Padovan" <padovan@...fusion.mobi>,
	"David S. Miller" <davem@...emloft.net>,
	linux-bluetooth@...r.kernel.org, linux-kernel@...r.kernel.org,
	netdev@...r.kernel.org, stable <stable@...r.kernel.org>
Subject: Re: [PATCH 1/2] bluetooth: hci_ldisc: fix NULL-pointer dereference
 on tty_close

Hi Johan,

> > > Do not close protocol driver until device has been unregistered.
> > > 
> > > This fixes a race between tty_close and hci_dev_open which can result in
> > > a NULL-pointer dereference.
> > > 
> > > The line discipline closes the protocol driver while we may still have
> > > hci_dev_open sleeping on the req_lock mutex resulting in a NULL-pointer
> > > dereference when lock is acquired and hci_init_req called.
> 
> [...]
> 
> > what kernel version is this against? Our changes in bluetooth-next fixed
> > some of the destruct handling.
> 
> This is against the latest rc as it needs to be fixed in 3.3, but I
> missed a dependency to bluetooth-next as you point out below.
> 
> > Also hci_unregister_dev should be calling the destruct handler and thus
> > your change is now accessing hu but it got freed already.
> 
> You're right, my patch depends on 010666a126fc ("Bluetooth: Make
> hci-destruct callback optional") and 797fe796c4 ("Bluetooth: uart-ldisc:
> Fix memory leak and remove destruct cb") from bluetooth-next. 
> 
> But since the latter one fixes a memory leak it should have been marked
> for stable as well as pushed to Linus for 3.3, right?

we need to look into this and propose patches for -stable. Is your
problem still present with bluetooth-next or not?

Regards

Marcel


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html