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 B32C730F949; Thu, 28 Aug 2025 12:19:11 +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=1756383553; cv=none; b=aSIYG3ELufTOG0K9kn0MMAFV8j1jAzFGkyLADG/qIfnRSguwSF1Kso3svOswgN7G4EUPvOtzoLtNqXPGGSlm+I+xQHAokh7jBohyZ3y9w+b0lqtTPeFrx3ha5rP8yQUn2g/5brnd3LdcWzLQzlq7hJqDmYELb79E/yJTfz5VIKQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756383553; c=relaxed/simple; bh=S/bf35zSjnC9ykYsPaCON3w96o/Y5nsFciW4cys1S+I=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=fc8RmuIagWW9rxd9ONbm7UEyV0Hap6Mrrll03S5UXcohGFpqn2qYEmBpBcHrj1jCQffWNIkDYnZyfBpWoMejYCJg5YiBh6VrBbO/g4HpvIPWSxiqYDrb9ag1IVD2Up2feadBGcRm96sjIZ4onGKVH98nDoUtwUVnJ65NhcVwj1I= 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 [172.19.162.112]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4cCL3D3G2bz24j1S; Thu, 28 Aug 2025 20:16:08 +0800 (CST) Received: from dggpemf500015.china.huawei.com (unknown [7.185.36.143]) by mail.maildlp.com (Postfix) with ESMTPS id 713991400DA; Thu, 28 Aug 2025 20:19:07 +0800 (CST) Received: from huawei.com (10.50.159.234) 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; Thu, 28 Aug 2025 20:19:06 +0800 From: Liu Jian To: , , , , , , , , , , , , CC: , , Subject: [PATCH net v2] net/smc: fix one NULL pointer dereference in smc_ib_is_sg_need_sync() Date: Thu, 28 Aug 2025 20:41:17 +0800 Message-ID: <20250828124117.2622624-1-liujian56@huawei.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: kwepems500002.china.huawei.com (7.221.188.17) To dggpemf500015.china.huawei.com (7.185.36.143) 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]=OOT_MODULE, [E]=UNSIGNED_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] ... Call Trace: smcr_buf_map_link+0x211/0x2a0 [smc] __smc_buf_create+0x522/0x970 [smc] smc_buf_create+0x3a/0x110 [smc] smc_find_rdma_v2_device_serv+0x18f/0x240 [smc] ? smc_vlan_by_tcpsk+0x7e/0xe0 [smc] smc_listen_find_device+0x1dd/0x2b0 [smc] smc_listen_work+0x30f/0x580 [smc] process_one_work+0x18c/0x340 worker_thread+0x242/0x360 kthread+0xe7/0x220 ret_from_fork+0x13a/0x160 ret_from_fork_asm+0x1a/0x30 If the software RoCE device is used, ibdev->dma_device is a null pointer. As a result, the problem occurs. Null pointer detection is added to prevent problems. Fixes: 0ef69e788411c ("net/smc: optimize for smc_sndbuf_sync_sg_for_device and smc_rmb_sync_sg_for_cpu") Signed-off-by: Liu Jian --- v1->v2: move the check outside of loop. net/smc/smc_ib.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c index 53828833a3f7..a42ef3f77b96 100644 --- a/net/smc/smc_ib.c +++ b/net/smc/smc_ib.c @@ -742,6 +742,9 @@ bool smc_ib_is_sg_need_sync(struct smc_link *lnk, unsigned int i; bool ret = false; + if (!lnk->smcibdev->ibdev->dma_device) + return ret; + /* for now there is just one DMA address */ for_each_sg(buf_slot->sgt[lnk->link_idx].sgl, sg, buf_slot->sgt[lnk->link_idx].nents, i) { -- 2.34.1