From patchwork Wed Aug 9 15:29:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Remi Pommarel X-Patchwork-Id: 13348120 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 77F6418AE1 for ; Wed, 9 Aug 2023 15:28:16 +0000 (UTC) Received: from relay4-d.mail.gandi.net (relay4-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::224]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 711B5E7F; Wed, 9 Aug 2023 08:28:13 -0700 (PDT) Received: by mail.gandi.net (Postfix) with ESMTPSA id 7382CE000B; Wed, 9 Aug 2023 15:28:10 +0000 (UTC) From: Remi Pommarel To: Marek Lindner , Simon Wunderlich , Antonio Quartulli , Sven Eckelmann Cc: "David S. Miller" , Eric Dumazet , b.a.t.m.a.n@lists.open-mesh.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Remi Pommarel , stable@vger.kernel.org Subject: [PATCH net] batman-adv: Fix batadv_v_ogm_aggr_send memory leak Date: Wed, 9 Aug 2023 17:29:13 +0200 Message-Id: <20230809152913.27218-1-repk@triplefau.lt> X-Mailer: git-send-email 2.40.0 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-GND-Sasl: repk@triplefau.lt X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_PASS,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: kuba@kernel.org When batadv_v_ogm_aggr_send is called for an inactive interface, the skb is silently dropped by batadv_v_ogm_send_to_if() but never freed causing the following memory leak: unreferenced object 0xffff00000c164800 (size 512): comm "kworker/u8:1", pid 2648, jiffies 4295122303 (age 97.656s) hex dump (first 32 bytes): 00 80 af 09 00 00 ff ff e1 09 00 00 75 01 60 83 ............u.`. 1f 00 00 00 b8 00 00 00 15 00 05 00 da e3 d3 64 ...............d backtrace: [<0000000007ad20f6>] __kmalloc_track_caller+0x1a8/0x310 [<00000000d1029e55>] kmalloc_reserve.constprop.0+0x70/0x13c [<000000008b9d4183>] __alloc_skb+0xec/0x1fc [<00000000c7af5051>] __netdev_alloc_skb+0x48/0x23c [<00000000642ee5f5>] batadv_v_ogm_aggr_send+0x50/0x36c [<0000000088660bd7>] batadv_v_ogm_aggr_work+0x24/0x40 [<0000000042fc2606>] process_one_work+0x3b0/0x610 [<000000002f2a0b1c>] worker_thread+0xa0/0x690 [<0000000059fae5d4>] kthread+0x1fc/0x210 [<000000000c587d3a>] ret_from_fork+0x10/0x20 Free the skb in that case to fix this leak. Cc: stable@vger.kernel.org Fixes: 0da0035942d4 ("batman-adv: OGMv2 - add basic infrastructure") Signed-off-by: Remi Pommarel --- net/batman-adv/bat_v_ogm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c index e710e9afe78f..445b06fc0d90 100644 --- a/net/batman-adv/bat_v_ogm.c +++ b/net/batman-adv/bat_v_ogm.c @@ -123,8 +123,10 @@ static void batadv_v_ogm_send_to_if(struct sk_buff *skb, { struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface); - if (hard_iface->if_status != BATADV_IF_ACTIVE) + if (hard_iface->if_status != BATADV_IF_ACTIVE) { + kfree_skb(skb); return; + } batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_TX); batadv_add_counter(bat_priv, BATADV_CNT_MGMT_TX_BYTES,