Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933411Ab0BDR3M (ORCPT ); Thu, 4 Feb 2010 12:29:12 -0500 Received: from kroah.org ([198.145.64.141]:34801 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933306Ab0BDRWL (ORCPT ); Thu, 4 Feb 2010 12:22:11 -0500 X-Mailbox-Line: From linux@linux.site Thu Feb 4 09:15:15 2010 Message-Id: <20100204171515.390422663@linux.site> User-Agent: quilt/0.47-14.9 Date: Thu, 04 Feb 2010 09:12:19 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Jarek Poplawski , "David S. Miller" , Greg Kroah-Hartman Subject: [48/74] ax25: netrom: rose: Fix timer oopses In-Reply-To: <20100204171850.GA16539@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4408 Lines: 147 2.6.32-stable review patch. If anyone has any objections, please let us know. ------------------ From: Jarek Poplawski [ Upstream commit d00c362f1b0ff54161e0a42b4554ac621a9ef92d ] Wrong ax25_cb refcounting in ax25_send_frame() and by its callers can cause timer oopses (first reported with 2.6.29.6 kernel). Fixes: http://bugzilla.kernel.org/show_bug.cgi?id=14905 Reported-by: Bernard Pidoux Tested-by: Bernard Pidoux Signed-off-by: Jarek Poplawski Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/net/netrom.h | 2 ++ net/ax25/ax25_out.c | 6 ++++++ net/netrom/nr_route.c | 11 ++++++----- net/rose/rose_link.c | 8 ++++++++ net/rose/rose_route.c | 5 +++++ 5 files changed, 27 insertions(+), 5 deletions(-) --- a/include/net/netrom.h +++ b/include/net/netrom.h @@ -132,6 +132,8 @@ static __inline__ void nr_node_put(struc static __inline__ void nr_neigh_put(struct nr_neigh *nr_neigh) { if (atomic_dec_and_test(&nr_neigh->refcount)) { + if (nr_neigh->ax25) + ax25_cb_put(nr_neigh->ax25); kfree(nr_neigh->digipeat); kfree(nr_neigh); } --- a/net/ax25/ax25_out.c +++ b/net/ax25/ax25_out.c @@ -92,6 +92,12 @@ ax25_cb *ax25_send_frame(struct sk_buff #endif } + /* + * There is one ref for the state machine; a caller needs + * one more to put it back, just like with the existing one. + */ + ax25_cb_hold(ax25); + ax25_cb_add(ax25); ax25->state = AX25_STATE_1; --- a/net/netrom/nr_route.c +++ b/net/netrom/nr_route.c @@ -842,12 +842,13 @@ int nr_route_frame(struct sk_buff *skb, dptr = skb_push(skb, 1); *dptr = AX25_P_NETROM; - ax25s = ax25_send_frame(skb, 256, (ax25_address *)dev->dev_addr, &nr_neigh->callsign, nr_neigh->digipeat, nr_neigh->dev); - if (nr_neigh->ax25 && ax25s) { - /* We were already holding this ax25_cb */ + ax25s = nr_neigh->ax25; + nr_neigh->ax25 = ax25_send_frame(skb, 256, + (ax25_address *)dev->dev_addr, + &nr_neigh->callsign, + nr_neigh->digipeat, nr_neigh->dev); + if (ax25s) ax25_cb_put(ax25s); - } - nr_neigh->ax25 = ax25s; dev_put(dev); ret = (nr_neigh->ax25 != NULL); --- a/net/rose/rose_link.c +++ b/net/rose/rose_link.c @@ -101,13 +101,17 @@ static void rose_t0timer_expiry(unsigned static int rose_send_frame(struct sk_buff *skb, struct rose_neigh *neigh) { ax25_address *rose_call; + ax25_cb *ax25s; if (ax25cmp(&rose_callsign, &null_ax25_address) == 0) rose_call = (ax25_address *)neigh->dev->dev_addr; else rose_call = &rose_callsign; + ax25s = neigh->ax25; neigh->ax25 = ax25_send_frame(skb, 260, rose_call, &neigh->callsign, neigh->digipeat, neigh->dev); + if (ax25s) + ax25_cb_put(ax25s); return (neigh->ax25 != NULL); } @@ -120,13 +124,17 @@ static int rose_send_frame(struct sk_buf static int rose_link_up(struct rose_neigh *neigh) { ax25_address *rose_call; + ax25_cb *ax25s; if (ax25cmp(&rose_callsign, &null_ax25_address) == 0) rose_call = (ax25_address *)neigh->dev->dev_addr; else rose_call = &rose_callsign; + ax25s = neigh->ax25; neigh->ax25 = ax25_find_cb(rose_call, &neigh->callsign, neigh->digipeat, neigh->dev); + if (ax25s) + ax25_cb_put(ax25s); return (neigh->ax25 != NULL); } --- a/net/rose/rose_route.c +++ b/net/rose/rose_route.c @@ -234,6 +234,8 @@ static void rose_remove_neigh(struct ros if ((s = rose_neigh_list) == rose_neigh) { rose_neigh_list = rose_neigh->next; + if (rose_neigh->ax25) + ax25_cb_put(rose_neigh->ax25); kfree(rose_neigh->digipeat); kfree(rose_neigh); return; @@ -242,6 +244,8 @@ static void rose_remove_neigh(struct ros while (s != NULL && s->next != NULL) { if (s->next == rose_neigh) { s->next = rose_neigh->next; + if (rose_neigh->ax25) + ax25_cb_put(rose_neigh->ax25); kfree(rose_neigh->digipeat); kfree(rose_neigh); return; @@ -810,6 +814,7 @@ void rose_link_failed(ax25_cb *ax25, int if (rose_neigh != NULL) { rose_neigh->ax25 = NULL; + ax25_cb_put(ax25); rose_del_route_by_neigh(rose_neigh); rose_kill_by_neigh(rose_neigh); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/