From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F39DFC00145 for ; Thu, 15 Dec 2022 08:06:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229619AbiLOIGD (ORCPT ); Thu, 15 Dec 2022 03:06:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54540 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229522AbiLOIGB (ORCPT ); Thu, 15 Dec 2022 03:06:01 -0500 Received: from mail-wr1-x433.google.com (mail-wr1-x433.google.com [IPv6:2a00:1450:4864:20::433]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5C35331DC9; Thu, 15 Dec 2022 00:05:59 -0800 (PST) Received: by mail-wr1-x433.google.com with SMTP id m14so2177044wrh.7; Thu, 15 Dec 2022 00:05:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :from:to:cc:subject:date:message-id:reply-to; bh=1BOtxxm4hSJIEL6wxTsNCBusLvyMX1O2ctAiD2U166U=; b=qwLfbdTpPpDW3TZKpZjHqYluZ04OdRP4nfrp9PgjuCj6pVh7syntbkMFo95OxE0jd0 8w6CsaZ9JQvQnyqDnGgUsCdoWMegtXeruTzHI7HzE7Z4EA9A/QlqzvExz0Npz3C1KmBc DKKT7CJFstdHgnnG7gwIc+UvF93CxWmSX+fXJLfAoWvxMrJQ5PqijSj98p/Lto6Y6rhi MXgSSlL01Dl489bBvQWBwvJHZO8K6qqXxAEmYuQX9qMsI3uml2I08HngLuf7SOZnlgb/ m7J9I40rWLhmzo2GQrfcc+ld0CqBKTUYkdWApXtgpxd02Tpvs688qrW5dx1NmpCmuEm1 0H7A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-disposition:mime-version:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=1BOtxxm4hSJIEL6wxTsNCBusLvyMX1O2ctAiD2U166U=; b=QmtNSy02St7FyUeBrfp00zaULy9kpFfdn3rDF8CUstZkDss5OXbA74932ykNu6kX7d r9ZYcw+nmue9EdMkKVrETlPmEe1eHfaSloJGrtagCruLsJ1cEzBzwoApnU7Ev/R6kWo5 xhMCAng8qGcPFv8gwTKw8eVmPlqjRNmPuLeJzxzS/aV5OjjaBVQSYNCMIxKXS1m660zU lvkBQ5lMfi3FKvPx22HjsG84EPl0dIj2xbU/TPSBB8tXY3qgqg6ymb4bg+eCpQnflRCp WHknn6+YS5tHEXUgj4y6G2NJlk7aFQKFaWuZEw1Bp+8qVvGbKXXHclzvO1yHB9TcJkW2 ieTA== X-Gm-Message-State: ANoB5pm9cS5ZuFS/e53gznlieAIWg71nSGK6XEgow9N4NfZ8uFvboR2s JtMs/v1Wj5s23LmItdJ1ZHE= X-Google-Smtp-Source: AA0mqf7vFP70Dy9aysz0sHb0joZrUkB4/zxZGB1oQh1CaPxICD2M8Ne+WYOpH6TSUFUV/c5CGfXnpA== X-Received: by 2002:a5d:61c9:0:b0:242:40de:332 with SMTP id q9-20020a5d61c9000000b0024240de0332mr15386068wrv.40.1671091557920; Thu, 15 Dec 2022 00:05:57 -0800 (PST) Received: from localhost ([102.36.222.112]) by smtp.gmail.com with ESMTPSA id k17-20020adfb351000000b002423edd7e50sm5308497wrd.32.2022.12.15.00.05.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 15 Dec 2022 00:05:57 -0800 (PST) Date: Thu, 15 Dec 2022 11:05:47 +0300 From: Dan Carpenter To: miquel.raynal@bootlin.com Cc: linux-wpan@vger.kernel.org, linux-wireless@vger.kernel.org Subject: [bug report] mac802154: Move an skb free within the rx path Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Hello Miquel Raynal, The patch 4d1c7d87030b: "mac802154: Move an skb free within the rx path" from Oct 26, 2022, leads to the following Smatch static checker warning: net/mac802154/rx.c:307 ieee802154_rx() warn: 'skb' was already freed. net/mac802154/rx.c 271 void ieee802154_rx(struct ieee802154_local *local, struct sk_buff *skb) 272 { 273 u16 crc; 274 275 WARN_ON_ONCE(softirq_count() == 0); 276 277 if (local->suspended) 278 goto free_skb; 279 280 /* TODO: When a transceiver omits the checksum here, we 281 * add an own calculated one. This is currently an ugly 282 * solution because the monitor needs a crc here. 283 */ 284 if (local->hw.flags & IEEE802154_HW_RX_OMIT_CKSUM) { 285 crc = crc_ccitt(0, skb->data, skb->len); 286 put_unaligned_le16(crc, skb_put(skb, 2)); 287 } 288 289 rcu_read_lock(); 290 291 ieee802154_monitors_rx(local, skb); 292 293 /* Level 1 filtering: Check the FCS by software when relevant */ 294 if (local->hw.phy->filtering == IEEE802154_FILTERING_NONE) { 295 crc = crc_ccitt(0, skb->data, skb->len); 296 if (crc) 297 goto drop; 298 } 299 /* remove crc */ 300 skb_trim(skb, skb->len - 2); 301 302 __ieee802154_rx_handle_packet(local, skb); This frees skb. 303 304 drop: 305 rcu_read_unlock(); 306 free_skb: --> 307 kfree_skb(skb); Double free. 308 } regards, dan carpenter