From nobody Sat Mar 19 17:53:35 2022 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id EDCBF1A284C9; Sat, 19 Mar 2022 17:53:35 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4KLT5C4vxMz4ccR; Sat, 19 Mar 2022 17:53:35 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1647712415; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=jKPwsTyk9FwSuRx0lQhqpFSoq3xkwLfHRGT/wPNsptU=; b=V7svcGORi4NrMMSo45L4S35X0m9Mx1g00dcLNP2M8+EP9GYJmjJNuDd6BYII6+CsUE1YMT PCbzyWs2OpsS6LPdim75kZdXf8fpmFdMaUkEGgHbeLYVsD2Tgi3DNdh98pBz4zOOWZ+x6N /CohA7lK+Kf/XXatDj2Kr1UQj/9SrZk1I0tj+rmuCRzgYIve/HJvBVBs4rzyu3ZJZu/2tC 26Wdr5D86xIH1Dw1NSFOdr0XqadEq/tbnUprSPvKWmTP9a5AXjhqJyIdd753dn68UuxbWO /1ZDeJAqHAMkzVsli37Ukv71nwSyPZCX1pKJiocDol1sM/nbQ72pwrp4B2zrdA== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 7743817C9F; Sat, 19 Mar 2022 17:53:35 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 22JHrZPH003983; Sat, 19 Mar 2022 17:53:35 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 22JHrZDD003982; Sat, 19 Mar 2022 17:53:35 GMT (envelope-from git) Date: Sat, 19 Mar 2022 17:53:35 GMT Message-Id: <202203191753.22JHrZDD003982@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Vincenzo Maffione Subject: git: 9f600a260a73 - stable/13 - netmap: Fix TOCTOU vulnerability in nmreq_copyin List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-all@freebsd.org X-BeenThere: dev-commits-src-all@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: vmaffione X-Git-Repository: src X-Git-Refname: refs/heads/stable/13 X-Git-Reftype: branch X-Git-Commit: 9f600a260a738d87015b2e9722b7b4f228cbd47d Auto-Submitted: auto-generated ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1647712415; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=jKPwsTyk9FwSuRx0lQhqpFSoq3xkwLfHRGT/wPNsptU=; b=gbw4QPPTv7iZubragxsDw4j7wA5jTZJhIC5g9AhAkGrqMRbpQ10lclCAHfZOB9V7QvgXGa g4SGNE+VFSa484VUsBBs8xo8KpkP5p4UETBnPomIdIYdHm7XYYcnu6br/QjmYN7V9BEMLI /T5i0FSGsRbbML1GquPaNZw6EN/tC0gmiKs+ByAS+DSaljHSkw6NzkbkvlddIU8gETCrXv N3LNhhQn0Rpjo4DF0v8aTM2nmtWCJmrAjYLIxB9+3e/9B/+hylwpD/zWFqw4QJgeedZ8nT 3e3VkxYCQDXzXJmYCHCqUU0H7Nmzv8qliWEjp16AZQKyZjH922xHmoIH/MKoaw== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1647712415; a=rsa-sha256; cv=none; b=GSYtS26GTyj58PE6xdTJXTAk9lJxvYSnYSdLEsAx5OeNl94y4pmkj7X+Z7TX8yRz54ytIi lyhNCCQQKR5hod6kwCci7BhzR7kpEArCG/Lb6zvFo/xO6u6k6LJr8QiBcDy70MQCqFqQqG C0RY6LxvE6Og6KYPmg/Avhvwp7JW/FmT88QNi5b7hU3uLogQY+6pADzHOcydAw6FajxVC6 kxyv/cAvCVWuvMcYOINcszMq6zrIFcUkg6A/gtA6/XA4j2S/bgHZ9k0Hy/YgPXBa0zLGr9 zISjg1Y9M2NyqNSgxppVAJrMkfPouYzJIKLpMJXmB1J/NbqRTSTszEbOxivZmw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none X-ThisMailContainsUnwantedMimeParts: N The branch stable/13 has been updated by vmaffione: URL: https://cgit.FreeBSD.org/src/commit/?id=9f600a260a738d87015b2e9722b7b4f228cbd47d commit 9f600a260a738d87015b2e9722b7b4f228cbd47d Author: Vincenzo Maffione AuthorDate: 2022-03-16 06:58:50 +0000 Commit: Vincenzo Maffione CommitDate: 2022-03-19 17:36:39 +0000 netmap: Fix TOCTOU vulnerability in nmreq_copyin The total size of the user-provided nmreq was first computed and then trusted during the copyin. This might lead to kernel memory corruption and escape from jails/containers. Reported by: Lucas Leong (@_wmliang_) of Trend Micro Zero Day Initiative Security: CVE-2022-23084 MFC after: 3 days (cherry picked from commit 393729916564ed13f966e09129a24e6931898d12) --- sys/dev/netmap/netmap.c | 51 +++++++++++++++++-------------------------------- 1 file changed, 17 insertions(+), 34 deletions(-) diff --git a/sys/dev/netmap/netmap.c b/sys/dev/netmap/netmap.c index 0c04098bb401..5baadc3e8014 100644 --- a/sys/dev/netmap/netmap.c +++ b/sys/dev/netmap/netmap.c @@ -3096,11 +3096,10 @@ nmreq_opt_size_by_type(uint32_t nro_reqtype, uint64_t nro_size) int nmreq_copyin(struct nmreq_header *hdr, int nr_body_is_user) { - size_t rqsz, optsz, bufsz, optbodysz; + size_t rqsz, optsz, bufsz; int error = 0; char *ker = NULL, *p; struct nmreq_option **next, *src, **opt_tab; - struct nmreq_option buf; uint64_t *ptrs; if (hdr->nr_reserved) { @@ -3130,39 +3129,14 @@ nmreq_copyin(struct nmreq_header *hdr, int nr_body_is_user) goto out_err; } - bufsz = 2 * sizeof(void *) + rqsz + - NETMAP_REQ_OPT_MAX * sizeof(opt_tab); - /* compute the size of the buf below the option table. - * It must contain a copy of every received option structure. - * For every option we also need to store a copy of the user - * list pointer. + /* + * The buffer size must be large enough to store the request body, + * all the possible options and the additional user pointers + * (2+NETMAP_REQ_OPT_MAX). Note that the maximum size of body plus + * options can not exceed NETMAP_REQ_MAXSIZE; */ - optsz = 0; - for (src = (struct nmreq_option *)(uintptr_t)hdr->nr_options; src; - src = (struct nmreq_option *)(uintptr_t)buf.nro_next) - { - error = copyin(src, &buf, sizeof(*src)); - if (error) - goto out_err; - /* Validate nro_size to avoid integer overflow of optsz and bufsz. */ - if (buf.nro_size > NETMAP_REQ_MAXSIZE) { - error = EMSGSIZE; - goto out_err; - } - optsz += sizeof(*src); - optbodysz = nmreq_opt_size_by_type(buf.nro_reqtype, buf.nro_size); - if (optbodysz > NETMAP_REQ_MAXSIZE) { - error = EMSGSIZE; - goto out_err; - } - optsz += optbodysz; - if (rqsz + optsz > NETMAP_REQ_MAXSIZE) { - error = EMSGSIZE; - goto out_err; - } - bufsz += sizeof(void *); - } - bufsz += optsz; + bufsz = (2 + NETMAP_REQ_OPT_MAX) * sizeof(void *) + NETMAP_REQ_MAXSIZE + + NETMAP_REQ_OPT_MAX * sizeof(opt_tab); ker = nm_os_malloc(bufsz); if (ker == NULL) { @@ -3200,6 +3174,7 @@ nmreq_copyin(struct nmreq_header *hdr, int nr_body_is_user) error = copyin(src, opt, sizeof(*src)); if (error) goto out_restore; + rqsz += sizeof(*src); /* make a copy of the user next pointer */ *ptrs = opt->nro_next; /* overwrite the user pointer with the in-kernel one */ @@ -3243,6 +3218,14 @@ nmreq_copyin(struct nmreq_header *hdr, int nr_body_is_user) /* copy the option body */ optsz = nmreq_opt_size_by_type(opt->nro_reqtype, opt->nro_size); + /* check optsz and nro_size to avoid for possible integer overflows of rqsz */ + if ((optsz > NETMAP_REQ_MAXSIZE) || (opt->nro_size > NETMAP_REQ_MAXSIZE) + || (rqsz + optsz > NETMAP_REQ_MAXSIZE) + || (optsz > 0 && rqsz + optsz <= rqsz)) { + error = EMSGSIZE; + goto out_restore; + } + rqsz += optsz; if (optsz) { /* the option body follows the option header */ error = copyin(src + 1, p, optsz);