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 X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D307BC47094 for ; Mon, 7 Jun 2021 15:34:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BCB0F61208 for ; Mon, 7 Jun 2021 15:34:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231224AbhFGPgV (ORCPT ); Mon, 7 Jun 2021 11:36:21 -0400 Received: from mail-pl1-f181.google.com ([209.85.214.181]:34525 "EHLO mail-pl1-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230239AbhFGPgU (ORCPT ); Mon, 7 Jun 2021 11:36:20 -0400 Received: by mail-pl1-f181.google.com with SMTP id h1so1241093plt.1 for ; Mon, 07 Jun 2021 08:34:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=73i5sakrC+i/nwD2XDXZACOiGIEuee7Cd/JkLRfjWDU=; b=GL/9X0t6PeQHVLfFDEvclaSHaaG+z6gqgsGNFmYhcSE+V/N5SWLFUE9+pXJHBg4G9R goUzHwlzrsVrOFtONjT4TPLqBtqW1v+/bk9YOx6yqM6cG+U19q3RcZTQ1vw1Ha8vejDS a7hJOmVwy9OojR2ZPie0yzHAGXKZAnE473DzJoI2LV27aGFZkxrSFaLkeSbF/L4zZ6el 8M+M1u/swgmrmyPq8UJjcw3oyfuFferMigYPXTXh6JH9ZWcTZ6knuWhhkMEYXDrpfE2N CSpxJsL1cCEHadBP3OJkJUu0+Hrm50xTCiMruIMRnHgGDeafks9XKnFEceez2VJjqIH5 pr+A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=73i5sakrC+i/nwD2XDXZACOiGIEuee7Cd/JkLRfjWDU=; b=ueXdq1BZXILSn/BBprh0W0/SMbX4LJuRnSSKWkCSQ48hdyizWm+9KybhansekqqIpQ tI8wiKStBF+gKCQQq57YPvXY32oQEFWHjx9Fichpgy1GFOWhbtDtApizzZFIHz9/eLns QPqPA+asiIPYfoQs2EQ5OL8az+EyDhTuD4RG9zGVBsyeTd5LV+lu6TiWaySwRPauA18w JAke5hapuVoIEmqLdEqmmCKNWkIk+Pzu8xFKgVmBtt0kdcMM+zWluzbim9n2bYmZBpSj sAPa97gpX7w7G1f61axNCKlaYAqVTbKhZr+FYmX0h87MzbiFDetUkGkYm08NwESOUPP5 1zCw== X-Gm-Message-State: AOAM532Z8BZku3/XBPRKya0N6VUmCWFfs4Ea7MVPX3TAJ9pofNdpO5LM pvTRkss4t2C6ZGX+VUgf7P/Z3i3rcFKLSTAK X-Google-Smtp-Source: ABdhPJwiigIXKgYCQ6iUifhbZgwYSJKZ0SAnMRVmqFzUbDiT0h/yeb/MM1nHg7njiWhAJnEBqCa8Mw== X-Received: by 2002:a17:902:7404:b029:101:af04:4e24 with SMTP id g4-20020a1709027404b0290101af044e24mr18782851pll.3.1623080008978; Mon, 07 Jun 2021 08:33:28 -0700 (PDT) Received: from hermes.local (76-14-218-44.or.wavecable.com. [76.14.218.44]) by smtp.gmail.com with ESMTPSA id g4sm9377305pgu.46.2021.06.07.08.33.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Jun 2021 08:33:28 -0700 (PDT) Date: Mon, 7 Jun 2021 08:33:25 -0700 From: Stephen Hemminger To: 13145886936@163.com Cc: davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, gushengxian Subject: Re: [PATCH] vlan: Avoid crashing the kernel Message-ID: <20210607083325.1a68e8e6@hermes.local> In-Reply-To: <20210607030839.374323-1-13145886936@163.com> References: <20210607030839.374323-1-13145886936@163.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Sun, 6 Jun 2021 20:08:39 -0700 13145886936@163.com wrote: > From: gushengxian > > Avoid crashing the kernel, try using WARN_ON & recovery code > rather than BUG() or BUG_ON(). > > Signed-off-by: gushengxian > --- > net/8021q/vlan.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c > index 4cdf8416869d..6e784fd8795b 100644 > --- a/net/8021q/vlan.c > +++ b/net/8021q/vlan.c > @@ -97,7 +97,7 @@ void unregister_vlan_dev(struct net_device *dev, struct list_head *head) > ASSERT_RTNL(); > > vlan_info = rtnl_dereference(real_dev->vlan_info); > - BUG_ON(!vlan_info); > + WARN_ON(!vlan_info); > > grp = &vlan_info->grp; NACK You change turns bug on into warning and crash from null pointer dereference.