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 5CF78C43334 for ; Tue, 7 Jun 2022 20:45:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376432AbiFGUpC (ORCPT ); Tue, 7 Jun 2022 16:45:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55134 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357962AbiFGTmg (ORCPT ); Tue, 7 Jun 2022 15:42:36 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E904B240; Tue, 7 Jun 2022 11:17:29 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id B8D3AB8237D; Tue, 7 Jun 2022 18:17:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 180F5C34115; Tue, 7 Jun 2022 18:17:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654625846; bh=fSFadVBx+9nhp9Vuit9XM8ZMa1aU8wtySBYdLPNXlHw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uJ9E9ZVnCeBSIb6hCdExtOtVS5iC5/yDZfGtbfPvK4TKB2mCuAcLUBa1c84hr9+Zz uD545kmlws2NOt0enIwdPGhpjhB1KTeqCVdV5FTUcnvTFKLs+7KE9SV+EfhFDOEeb3 N3C+UzT5LBV2mxsJ2wiyMSJqPdGvmS4E4RoT3brg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , "David S. Miller" , Sasha Levin Subject: [PATCH 5.17 125/772] net: remove two BUG() from skb_checksum_help() Date: Tue, 7 Jun 2022 18:55:17 +0200 Message-Id: <20220607164952.729252642@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220607164948.980838585@linuxfoundation.org> References: <20220607164948.980838585@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Dumazet [ Upstream commit d7ea0d9df2a6265b2b180d17ebc64b38105968fc ] I have a syzbot report that managed to get a crash in skb_checksum_help() If syzbot can trigger these BUG(), it makes sense to replace them with more friendly WARN_ON_ONCE() since skb_checksum_help() can instead return an error code. Note that syzbot will still crash there, until real bug is fixed. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/core/dev.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index 5f1ac4812277..f2ce184d7223 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3156,11 +3156,15 @@ int skb_checksum_help(struct sk_buff *skb) } offset = skb_checksum_start_offset(skb); - BUG_ON(offset >= skb_headlen(skb)); + ret = -EINVAL; + if (WARN_ON_ONCE(offset >= skb_headlen(skb))) + goto out; + csum = skb_checksum(skb, offset, skb->len - offset, 0); offset += skb->csum_offset; - BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb)); + if (WARN_ON_ONCE(offset + sizeof(__sum16) > skb_headlen(skb))) + goto out; ret = skb_ensure_writable(skb, offset + sizeof(__sum16)); if (ret) -- 2.35.1