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 0E5672F746F; Tue, 26 Aug 2025 08:22:28 +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=1756196552; cv=none; b=NAUHI/cfSRrMbjNd2tbwaw/mhn5njiJZwLAyaZkOcC/kIwRpDaawEZurxlen/d3KZ2n2/fq1qFyzsBd5qIyDfEMAUNGRetx8+gk1N3ojvPO8qmGmHm0NlIKYY6iWlEjVrb1eNRhvOKn6KPITQTZhHMnm/jWOjRZJ0XGSWzNTrGc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756196552; c=relaxed/simple; bh=paTBoj9DCUhl33v0IoUbRwFxDjdcIXIy94zu1Z1jVGg=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=ccd7sRZPPTwDXyzmLdsY+wBuinhm10z445l7t26tWd9WAaYpD4Z0K0dsKeOOBUEhFqCfxxC4eASwSJ2LV7Igq+ezWvfxOICwFYYabPGxx5WyMw8oaQ3YofnDUsaTQ901OvQUratky6c0ksP5KigeWQigMpim4jn7Fbks2+GJ1Ck= 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 4cB0v60bh9z1R96x; Tue, 26 Aug 2025 16:19:30 +0800 (CST) Received: from dggpemf500015.china.huawei.com (unknown [7.185.36.143]) by mail.maildlp.com (Postfix) with ESMTPS id D36CE1402CA; Tue, 26 Aug 2025 16:22:25 +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; Tue, 26 Aug 2025 16:22:24 +0800 From: Liu Jian To: , , , , , , , , , , , , CC: , , Subject: [PATCH net] net/smc: fix one NULL pointer dereference in smc_ib_is_sg_need_sync() Date: Tue, 26 Aug 2025 16:44:42 +0800 Message-ID: <20250826084442.322587-1-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: kwepems500001.china.huawei.com (7.221.188.70) 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 --- net/smc/smc_ib.c | 2 ++ 1 file changed, 2 insertions(+) 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; if (dma_need_sync(lnk->smcibdev->ibdev->dma_device, sg_dma_address(sg))) { ret = true; -- 2.34.1