From nobody Tue Nov 29 22:56:47 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 4NMHlN0Qmmz4hmKs; Tue, 29 Nov 2022 22:56:48 +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 4NMHlM6ylsz3sJ9; Tue, 29 Nov 2022 22:56:47 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1669762608; 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=CX46DpRA03B6/3DifgMZAGBe2VkB5wC4VCuiHvPPdis=; b=TV5JoibpgzeZHCiLelaAXLtYUbXOBCD1EqhK2HatnzFbBFLA5u28zS34rZwFWGAcT54FaB snOzAfEJXJZ5py5cQkNQFI0OcTSCeBOTJHOwSCofWeo2yUgGuOjiCm+KEPsYwiXafOfbXw vRI1rd8Cp2stKyGzNpcR3kR8jSLE7/pkYMbgPvJnCkQPBVZxYfyTI/4AO1MzThoaPP6x/1 Ecmsj85BDbaZNuK85p0tLO+V2KODhaIAOKyXSjXmtuYNxTCNkFaSMb0/XO9PoHHui8tIH0 04jlhpj27RAGJkjLrQd+iCaMyW8fczh3cuH4axCr9lclzrp6zZbESDNNTb27YQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1669762608; 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=CX46DpRA03B6/3DifgMZAGBe2VkB5wC4VCuiHvPPdis=; b=UMwmbvIefG3YTsAE0Chm1MFo7ebXf0hp2pptMQuSLL+KFupm0DJ2UCHSQM4OBS1B8ELlVl K4qF1K1SrOvJpIpsSUgwqrzGD2zaI7+yEA9wyN2UJgkRt8JCEXm7Wlp8Um2WvTQD7vJG5y Kl5uy22MUR7Oj+nHvwKOFCNDmYUwmT58II8xpmKadOvTDYJ+wGgC4EbJUhiIMa9FMWoLYB 1hiy4AqHFztAhWpV52HZYsAZ+zKVsAqGndqCbuSwJuYd1ncceSEvkdYVr7+SmL60jXP57/ XDx1U4jx3GtmlUUn6zk72EbLkbkoiQh8yyEUi0UOTo/LBcJSegr0YHMe5CmtBw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1669762608; a=rsa-sha256; cv=none; b=KNwBN8OV6oy9uPM04XfJTdJ1M6XH/lYM/nU6ziewVFYnXdobN4GzNFBF45Xpj/4Djwt/T/ 3MOTFwgcygvBbUjSutuJys3bwrN4+AYmMuFCMkZGJjDMz0+l4hQhSFaPN4E0+K73QhWovX pPAfjx4k0TQ/sz1OUODj4vkSYW8SdTC2J0wMdrKopFvfMod9MP9Y/rL51lxPDnKX4ydbEp sBi/JPzJUYBLGO+XnhgjnEYEsDKMBsFgKdCuHXti+5b6F3PDpBbz6sOmaiZiNhMzPevxuA qLUOyU8MZTRqwc66feVFTA7d7va/L7UKC9pnQvhJsXjU9+JB9PeiiHhQGUVb6Q== 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 4NMHlM60djzZMQ; Tue, 29 Nov 2022 22:56:47 +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 2ATMulds098134; Tue, 29 Nov 2022 22:56:47 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 2ATMul3H098133; Tue, 29 Nov 2022 22:56:47 GMT (envelope-from git) Date: Tue, 29 Nov 2022 22:56:47 GMT Message-Id: <202211292256.2ATMul3H098133@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Gordon Tetlow Subject: git: 186f495d4be1 - stable/13 - ping: Fix handling of IP packet sizes 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: gordon X-Git-Repository: src X-Git-Refname: refs/heads/stable/13 X-Git-Reftype: branch X-Git-Commit: 186f495d4be12a9184d2b11183c55b27b879765f Auto-Submitted: auto-generated X-ThisMailContainsUnwantedMimeParts: N The branch stable/13 has been updated by gordon: URL: https://cgit.FreeBSD.org/src/commit/?id=186f495d4be12a9184d2b11183c55b27b879765f commit 186f495d4be12a9184d2b11183c55b27b879765f Author: Tom Jones AuthorDate: 2022-11-17 10:31:38 +0000 Commit: Gordon Tetlow CommitDate: 2022-11-29 22:56:33 +0000 ping: Fix handling of IP packet sizes Ping reads raw IP packets to parse ICMP responses. When reading the IP Header Len (IHL) ping was was taking the value from the provided packet without any validation. This could lead to remotely triggerable stack corruption. Validate the IHL against expected and recieved data sizes when reading from the received packet and when reading any quoted packets from within the ICMP response. Approved by: so Reviewed by: markj, asomers Security: FreeBSD-SA-22:15.ping Security: CVE-2022-23093 Sponsored by: NetApp, Inc. Sponsored by: Klara, Inc. X-NetApp-PR: #77 Differential Revision: https://reviews.freebsd.org/D37195 (cherry picked from commit 46d7b45a267b3d78c5054b210ff7b6c55bfca42b) --- sbin/ping/ping.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 60 insertions(+), 9 deletions(-) diff --git a/sbin/ping/ping.c b/sbin/ping/ping.c index be1ccfe29d23..00ac8eadddff 100644 --- a/sbin/ping/ping.c +++ b/sbin/ping/ping.c @@ -952,6 +952,9 @@ ping(int argc, char *const *argv) warn("recvmsg"); continue; } + /* If we have a 0 byte read from recvfrom continue */ + if (cc == 0) + continue; #ifdef SO_TIMESTAMP if (cmsg != NULL && cmsg->cmsg_level == SOL_SOCKET && @@ -1133,8 +1136,10 @@ pr_pack(char *buf, ssize_t cc, struct sockaddr_in *from, struct timespec *tv) struct icmp icp; struct ip ip; const u_char *icmp_data_raw; + ssize_t icmp_data_raw_len; double triptime; - int dupflag, hlen, i, j, recv_len; + int dupflag, i, j, recv_len; + uint8_t hlen; uint16_t seq; static int old_rrlen; static char old_rr[MAX_IPOPTLEN]; @@ -1144,15 +1149,27 @@ pr_pack(char *buf, ssize_t cc, struct sockaddr_in *from, struct timespec *tv) const u_char *oicmp_raw; /* - * Get size of IP header of the received packet. The - * information is contained in the lower four bits of the - * first byte. + * Get size of IP header of the received packet. + * The header length is contained in the lower four bits of the first + * byte and represents the number of 4 byte octets the header takes up. + * + * The IHL minimum value is 5 (20 bytes) and its maximum value is 15 + * (60 bytes). */ memcpy(&l, buf, sizeof(l)); hlen = (l & 0x0f) << 2; - memcpy(&ip, buf, hlen); - /* Check the IP header */ + /* Reject IP packets with a short header */ + if (hlen < sizeof(struct ip)) { + if (options & F_VERBOSE) + warn("IHL too short (%d bytes) from %s", hlen, + inet_ntoa(from->sin_addr)); + return; + } + + memcpy(&ip, buf, sizeof(struct ip)); + + /* Check packet has enough data to carry a valid ICMP header */ recv_len = cc; if (cc < hlen + ICMP_MINLEN) { if (options & F_VERBOSE) @@ -1164,6 +1181,7 @@ pr_pack(char *buf, ssize_t cc, struct sockaddr_in *from, struct timespec *tv) #ifndef icmp_data icmp_data_raw = buf + hlen + offsetof(struct icmp, icmp_ip); #else + icmp_data_raw_len = cc - (hlen + offsetof(struct icmp, icmp_data)); icmp_data_raw = buf + hlen + offsetof(struct icmp, icmp_data); #endif @@ -1293,12 +1311,45 @@ pr_pack(char *buf, ssize_t cc, struct sockaddr_in *from, struct timespec *tv) * as root to avoid leaking information not normally * available to those not running as root. */ + + /* + * If we don't have enough bytes for a quoted IP header and an + * ICMP header then stop. + */ + if (icmp_data_raw_len < + (ssize_t)(sizeof(struct ip) + sizeof(struct icmp))) { + if (options & F_VERBOSE) + warnx("quoted data too short (%zd bytes) from %s", + icmp_data_raw_len, inet_ntoa(from->sin_addr)); + return; + } + memcpy(&oip_header_len, icmp_data_raw, sizeof(oip_header_len)); oip_header_len = (oip_header_len & 0x0f) << 2; - memcpy(&oip, icmp_data_raw, oip_header_len); + + /* Reject IP packets with a short header */ + if (oip_header_len < sizeof(struct ip)) { + if (options & F_VERBOSE) + warnx("inner IHL too short (%d bytes) from %s", + oip_header_len, inet_ntoa(from->sin_addr)); + return; + } + + /* + * Check against the actual IHL length, to protect against + * quoated packets carrying IP options. + */ + if (icmp_data_raw_len < + (ssize_t)(oip_header_len + sizeof(struct icmp))) { + if (options & F_VERBOSE) + warnx("inner packet too short (%zd bytes) from %s", + icmp_data_raw_len, inet_ntoa(from->sin_addr)); + return; + } + + memcpy(&oip, icmp_data_raw, sizeof(struct ip)); oicmp_raw = icmp_data_raw + oip_header_len; - memcpy(&oicmp, oicmp_raw, offsetof(struct icmp, icmp_id) + - sizeof(oicmp.icmp_id)); + memcpy(&oicmp, oicmp_raw, sizeof(struct icmp)); if (((options & F_VERBOSE) && uid == 0) || (!(options & F_QUIET2) &&