linux-kernel - [PATCH] hso: fix refcnt leak in recent patch.

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-next>] [day] [month] [year] [list]

Message-ID: <20150414093634.4fe24ba3@notabene.brown>
Date:	Tue, 14 Apr 2015 09:36:34 +1000
From:	NeilBrown <neilb@...e.de>
To:	Olivier Sobrie <olivier@...rie.be>,
	"David S. Miller" <davem@...emloft.net>,
	Jan Dumon <j.dumon@...ion.com>
Cc:	linux-usb@...r.kernel.org, netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	GTA04 owners <gta04-owner@...delico.com>
Subject: [PATCH] hso: fix refcnt leak in recent patch.



Prior to
commit 29bd3bc1194c624ce863cab2a7da9bc1f0c3b47b
    hso: fix crash when device disappears while serial port is open

hso_serial_open would always kref_get(&serial->parent->ref) before
returning zero.
Since that commit, it only calls kref_get when returning 0 if
serial->port.count was zero.

This results in calls to
       kref_put(&serial->parent->ref, hso_serial_ref_free);

after hso_serial_ref_free has been called, which dereferences a freed
pointer.

This patch adds the missing kref_get().

Fixes: commit 29bd3bc1194c624ce863cab2a7da9bc1f0c3b47b
Cc: stable@...r.kernel.org (v4.0)
Cc: Olivier Sobrie <olivier@...rie.be>
Signed-off-by: NeilBrown <neilb@...e.de>

diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c
index 75befc1bd816..6848fc903340 100644
--- a/drivers/net/usb/hso.c
+++ b/drivers/net/usb/hso.c
@@ -1299,6 +1299,7 @@ static int hso_serial_open(struct tty_struct *tty, struct file *filp)
 		}
 	} else {
 		D1("Port was already open");
+		kref_get(&serial->parent->ref);
 	}
 
 	usb_autopm_put_interface(serial->parent->interface);

Content of type "application/pgp-signature" skipped