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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 78356C433F5 for ; Fri, 27 May 2022 08:29:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:CC :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=rIh6a7Lt7FOoF9Ck2wcaHHxRCJPQkTmWjMWq3AdUE20=; b=bJje7iZKjVA9rw C0Ju+cuqOuZ2jTfVuM9f4DYurmvU9AGwgQnjjoK/fF9zs/KVJ3ppVak1MaE6NQNU71vFUVw/2iM4/ A+hdkpgJ6+shulpGmX20erelYZpmrosVqP46o9CkOR7bxM7R0y2/Xp0kwHQOcxTiJ4ThydqXDGguR sLJHzbQrQ2CNBPH6QBx61DcMwtvYei5L6gv4I5wOAlv4GIebHz65eKA+epWFEfinDJpRQA1NI1j5k y+ysI8r936p1WSdV/4ja9eUcel7W9RU9zQYmVBhIst4yMoQvpU4H+Q4RHx7REffcV+0l08BHidzc2 Dv9GF1ox0HrCDqIOJ5qA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nuVK7-00H1Cw-FE; Fri, 27 May 2022 08:27:55 +0000 Received: from szxga01-in.huawei.com ([45.249.212.187]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nuVK3-00H1BQ-Cy for linux-arm-kernel@lists.infradead.org; Fri, 27 May 2022 08:27:53 +0000 Received: from dggpemm500024.china.huawei.com (unknown [172.30.72.57]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4L8dFY3tkXzjX5S; Fri, 27 May 2022 16:26:57 +0800 (CST) Received: from dggpemm500006.china.huawei.com (7.185.36.236) by dggpemm500024.china.huawei.com (7.185.36.203) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 27 May 2022 16:27:38 +0800 Received: from mdc.huawei.com (10.175.112.208) by dggpemm500006.china.huawei.com (7.185.36.236) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Fri, 27 May 2022 16:27:37 +0800 From: Chen Jun To: , , , CC: Subject: [PATCH] arm64/smp: check !ipi_desc[i] in arch_show_interrupts Date: Fri, 27 May 2022 08:22:36 +0000 Message-ID: <20220527082236.78037-1-chenjun102@huawei.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-Originating-IP: [10.175.112.208] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpemm500006.china.huawei.com (7.185.36.236) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220527_012751_676404_93E50CC3 X-CRM114-Status: UNSURE ( 9.36 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org There is a potential dereferencing null pointer issue in arch_show_interrupts. Problem 1: int arch_show_interrupts(struct seq_file *p, int prec) for (i = 0; i < NR_IPI; i++) { seq_printf(p, "%10u ", irq_desc_kstat_cpu(ipi_desc[i], cpu)); Only ipi_desc[0..nr_ipi - 1] are initialized in set_smp_ipi_range. and ipi_desc[nr_ipi..NR_IPI] are NULL. irq_desc_kstat_cpu will dereference NULL pointer. For now, the problem can not be triggered, because NR_IPI is always equal to nr_ipi. Problem 2: If request_percpu_irq failed in set_smp_ipi_range, ipi_desc[i] would be NULL. irq_desc_kstat_cpu will dereference NULL pointer. check !ipi_desc[i] (as arm does) to avoid the problem. Signed-off-by: Chen Jun --- arch/arm64/kernel/smp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 62ed361a4376..3d54f464428b 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -781,6 +781,9 @@ int arch_show_interrupts(struct seq_file *p, int prec) unsigned int cpu, i; for (i = 0; i < NR_IPI; i++) { + if (!ipi_desc[i]) + continue; + seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i, prec >= 4 ? " " : ""); for_each_online_cpu(cpu) -- 2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel