From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga05-in.huawei.com (szxga05-in.huawei.com [45.249.212.191]) (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 77CD734A334; Wed, 27 Aug 2025 10:48:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.191 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756291725; cv=none; b=E5/GxLLPGt8btHHzRXSap/kKINZy8zmS4ZO52bGUm5eBH921IYcunRiixKtpJmt1M7PijDX3UyvvshaUFv1XAH4jEfW/7V+FfsMIu5jsloW909/SpZdqYQ+YGBBvUMwVf8hq569gjCGgzC8eNvixVIS/gzfkcSaL+dU/loleHj4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756291725; c=relaxed/simple; bh=4QChEoRjqWHTne5COgEK+7FgPenEtjJhU59F2PQTz28=; h=From:To:CC:Subject:Date:Message-ID:References:In-Reply-To: Content-Type:MIME-Version; b=UeRi9ek2SeGM1oW/onmGJjfu/g490kh5co9BUQbDQ5n3KXaZfd4ZmGxip5PXXTkCUCTuUbOejS526hzypxwJKMpqj6HKpuF3GHauyPJLzs1b8JTLzDiXAU12Yf2y8rFEymvNaQas3ufhkOEn30ATZ7Hpi7wr2cz3wSuhH2fRSXI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.191 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.88.234]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4cBh5L2d6nz24htl; Wed, 27 Aug 2025 18:45:42 +0800 (CST) Received: from dggpemf500015.china.huawei.com (unknown [7.185.36.143]) by mail.maildlp.com (Postfix) with ESMTPS id 0588B140109; Wed, 27 Aug 2025 18:48:40 +0800 (CST) Received: from dggpemf500015.china.huawei.com (7.185.36.143) by dggpemf500015.china.huawei.com (7.185.36.143) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Wed, 27 Aug 2025 18:48:39 +0800 Received: from dggpemf500015.china.huawei.com ([7.185.36.143]) by dggpemf500015.china.huawei.com ([7.185.36.143]) with mapi id 15.02.1544.011; Wed, 27 Aug 2025 18:48:39 +0800 From: "liujian (CE)" To: "D. Wythe" CC: "dust.li@linux.alibaba.com" , "sidraya@linux.ibm.com" , "wenjia@linux.ibm.com" , "mjambigi@linux.ibm.com" , "tonylu@linux.alibaba.com" , "guwen@linux.alibaba.com" , "davem@davemloft.net" , "edumazet@google.com" , "kuba@kernel.org" , "pabeni@redhat.com" , "horms@kernel.org" , "guangguan.wang@linux.alibaba.com" , "linux-rdma@vger.kernel.org" , "linux-s390@vger.kernel.org" , "netdev@vger.kernel.org" Subject: RE: [PATCH net] net/smc: fix one NULL pointer dereference in smc_ib_is_sg_need_sync() Thread-Topic: [PATCH net] net/smc: fix one NULL pointer dereference in smc_ib_is_sg_need_sync() Thread-Index: AQHcFmKWx5M9zwvyZkS3sfn5/yfKorR0KFsAgAIq2qA= Date: Wed, 27 Aug 2025 10:48:39 +0000 Message-ID: <9ae4d764df69431cb77f5c5c32eaa911@huawei.com> References: <20250826084442.322587-1-liujian56@huawei.com> <20250826094138.GA67990@j66a10360.sqa.eu95> In-Reply-To: <20250826094138.GA67990@j66a10360.sqa.eu95> Accept-Language: zh-CN, en-US Content-Language: zh-CN X-MS-Has-Attach: X-MS-TNEF-Correlator: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 > -----Original Message----- > From: D. Wythe [mailto:alibuda@linux.alibaba.com] > Sent: Tuesday, August 26, 2025 5:42 PM > To: liujian (CE) > Cc: alibuda@linux.alibaba.com; dust.li@linux.alibaba.com; > sidraya@linux.ibm.com; wenjia@linux.ibm.com; mjambigi@linux.ibm.com; > tonylu@linux.alibaba.com; guwen@linux.alibaba.com; > davem@davemloft.net; edumazet@google.com; kuba@kernel.org; > pabeni@redhat.com; horms@kernel.org; > guangguan.wang@linux.alibaba.com; linux-rdma@vger.kernel.org; linux- > s390@vger.kernel.org; netdev@vger.kernel.org > Subject: Re: [PATCH net] net/smc: fix one NULL pointer dereference in > smc_ib_is_sg_need_sync() >=20 > On Tue, Aug 26, 2025 at 04:44:42PM +0800, Liu Jian wrote: > > BUG: kernel NULL pointer dereference, address: 00000000000002ec PGD 0 > > P4D 0 > > Oops: Oops: 0000 [#1] SMP PTI > > CPU: 28 UID: 0 PID: 343 Comm: kworker/28:1 Kdump: loaded Tainted: G > OE 6.17.0-rc2+ #9 NONE > > Tainted: [O]=3DOOT_MODULE, [E]=3DUNSIGNED_MODULE Hardware name: > QEMU > > Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 > > Workqueue: smc_hs_wq smc_listen_work [smc] > > RIP: 0010:smc_ib_is_sg_need_sync+0x9e/0xd0 [smc] > > > > diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c index > > 53828833a3f7..85501d2c1f1b 100644 > > --- a/net/smc/smc_ib.c > > +++ b/net/smc/smc_ib.c > > @@ -747,6 +747,8 @@ bool smc_ib_is_sg_need_sync(struct smc_link *lnk, > > buf_slot->sgt[lnk->link_idx].nents, i) { > > if (!sg_dma_len(sg)) > > break; > > + if (!lnk->smcibdev->ibdev->dma_device) > > + break; >=20 > Why check it inside the loop? Ok, will send v2, move the check outside of loop. Thanks.