From patchwork Sun Oct 23 16:39:47 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hawkins Jiawei X-Patchwork-Id: 13016340 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 0ED90ECAAA1 for ; Sun, 23 Oct 2022 16:42:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230408AbiJWQmS (ORCPT ); Sun, 23 Oct 2022 12:42:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45448 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229772AbiJWQmR (ORCPT ); Sun, 23 Oct 2022 12:42:17 -0400 Received: from mail-pj1-x102b.google.com (mail-pj1-x102b.google.com [IPv6:2607:f8b0:4864:20::102b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 095A130F7A; Sun, 23 Oct 2022 09:42:17 -0700 (PDT) Received: by mail-pj1-x102b.google.com with SMTP id m6-20020a17090a5a4600b00212f8dffec9so1650133pji.0; Sun, 23 Oct 2022 09:42:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=y/JN3nDWwlvz0zr+zWQj4q64audZwnviw+yHCDgZXPo=; b=gZsn90LXl5nV61F9U0RAcTQqSQZdYebM2knsbimY3UTaxWa5vVVyv5Nk2qgPQ22FBc R3+gW5rWNzdCx3xJ8nDUsQJCwpWKlLcPAk7rlAoMMIo92R4T+Z0iTtqBop0YDAWHs9uK 2tan3wUNJhE0AA84wdSBWgHglSZuhsKsdV24N1z/dVDwodFJUJJohTdTb10aZ3q7kyzO HN8qm+ZCa2pmsgf1LrSkVov9bijdkrdeRB0k9Uia8aPI/O6KNyjbly4gzuWnPv9ZB2bF 7ATVOQvh2cDtNLGkksEIYvsD7ENevD2AoUF08EZmvjHvK7eTsNXc9avLnmyMo0JJomzs onjg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=y/JN3nDWwlvz0zr+zWQj4q64audZwnviw+yHCDgZXPo=; b=kTfl7I6DZkaUDpwh1ZHpudf8xmU4sVgiaaqKz2D108AxcV0O0tKm+jIngfO8IGpH7P /Ji8LZMgT1v5IC5LJ/EcMtr2AfQxejZur7VDmRGyT9XYLUwIkqh73WY+rS/ZuSwTy/Vq VqJkZRbffMI29aoi8Lt/35z4RTBYHFVfaZDbaDGRIPW7ZDU/10hNHUjvUrqVDX2Hhxcr DTQRqBHwXUkPnkbvH/ZnCTYvWpszDxmEF5Ys1XeGyCur/0IE46AqW0ZrSEIrAkK6pH4Q cw/7cwb78XmVHk1W/ZTo4XX0HXT6zjD7aZRHKsLj2UQR84j43qkeoU4m4ILuDayQl/XG EmYQ== X-Gm-Message-State: ACrzQf3aTw9uhw+F9DoOn5itSi565IL5CbP8reuIlcOo+SMdGzT+NJuh 9FtgPNV4ePV5911pbu6ItQo= X-Google-Smtp-Source: AMsMyM5zNx6aq+Gv68lpF7ZJA9MebNHteDpkuxTUQkSuQuvYV7T9nBmrooZ0dTjV6fKFMK4f9zkD9Q== X-Received: by 2002:a17:90b:38d1:b0:20d:8f2a:c4c4 with SMTP id nn17-20020a17090b38d100b0020d8f2ac4c4mr67611720pjb.192.1666543336554; Sun, 23 Oct 2022 09:42:16 -0700 (PDT) Received: from localhost ([223.104.41.250]) by smtp.gmail.com with ESMTPSA id y199-20020a6264d0000000b0056b9a740ec2sm2259225pfb.156.2022.10.23.09.42.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 23 Oct 2022 09:42:16 -0700 (PDT) From: Hawkins Jiawei To: yin31149@gmail.com, Xiubo Li , Ilya Dryomov , Jeff Layton Cc: 18801353760@163.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, ceph-devel@vger.kernel.org Subject: [PATCH -next 3/5] ceph: fix possible null-ptr-deref when parsing param Date: Mon, 24 Oct 2022 00:39:47 +0800 Message-Id: <20221023163945.39920-4-yin31149@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221023163945.39920-1-yin31149@gmail.com> References: <20221023163945.39920-1-yin31149@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org According to commit "vfs: parse: deal with zero length string value", kernel will set the param->string to null pointer in vfs_parse_fs_string() if fs string has zero length. Yet the problem is that, ceph_parse_mount_param() will dereferences the param->string, without checking whether it is a null pointer, which may trigger a null-ptr-deref bug. This patch solves it by adding sanity check on param->string in ceph_parse_mount_param(). Signed-off-by: Hawkins Jiawei --- fs/ceph/super.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/ceph/super.c b/fs/ceph/super.c index 3fc48b43cab0..341e23fe29eb 100644 --- a/fs/ceph/super.c +++ b/fs/ceph/super.c @@ -417,6 +417,9 @@ static int ceph_parse_mount_param(struct fs_context *fc, param->string = NULL; break; case Opt_mds_namespace: + if (!param->string) + return invalfc(fc, "Bad value '%s' for mount option '%s'\n", + param->string, param->key); if (!namespace_equals(fsopt, param->string, strlen(param->string))) return invalfc(fc, "Mismatching mds_namespace"); kfree(fsopt->mds_namespace);