From nobody Tue Nov 29 22:56:26 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 4NMHky6yDmz4hmKn; Tue, 29 Nov 2022 22:56:26 +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 4NMHky6N4Sz3sPv; Tue, 29 Nov 2022 22:56:26 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1669762586; 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=uNsm8rAM7dhNmHBMQhrSiEgausnOXo6zk8bAilPx8hM=; b=CiB7tnvSru4WBDQ+D0WS1j9X3VxOTNaQTRRciR4zF0b1CAY/SpiiRMJkI6IXFSTpmqfuz4 XxxlrFcXJg/qu4HcZIYnyHab0iYnr25cDiK8TbQq4zlYNIETyDgZJvr9U55JpPMFimDivX Yr4H5XwVkI+CgoHPIUsiCNfxYL6IrpnTEy39jddP9D/bpfXqCIW9sTTDHLDAn2gDNM0gxI wlk95F2tgI5+Fuk4TgVX3ewDyNkR7UVpwxJjiNIixnJQ6Swb07/+1cGZRylnyck9hupMK8 156d8ED4aRrfcHOx/9kcDcoGLzukY758QpqxpQ0wB6xnu1bQe8s9edtJfXXjCQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1669762586; 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=uNsm8rAM7dhNmHBMQhrSiEgausnOXo6zk8bAilPx8hM=; b=ZuMoHmKsmIvNdAfdoEibF6zUedlSvi+rg6tnWi3FIJB8M97fDMhdHP9c4LnTRlfrDGdFQB NjSAhcYzJjyLJCrcT17tSM7FqaEjO5crLLHwZwUQsmhhc1Bu+zEkqqz5ov5DsKmjtJijj8 CiJ3/TsbWIKNZOeT6UWdWaXbFRZvqYOiHClD9Wvlcua2AR8aEC8xWv5oz/0QJpa1X95cXj J/ITODLNUI/X+Y3dbssCGmeh853lMN1H9LXPreQAEnh3fvrGkPNcsuAYf11U45clAiVfiL 4R/w/hyFwqo8pmq86+RRX/uGxo4GKUjWvTL5+oDX2nlNGEjPvH93GuBKXvL/nw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1669762586; a=rsa-sha256; cv=none; b=meWbqbeaMq/egLkoWqHVu0ZoLCahUq0Nn8EJ8SL0lCQMHvKbHM2nDIZPf5XKG1uSbxsMP3 es6I3h6DjLXMw6kx7dlSxC6YX70UrVygl33Yy74UDta3QkBl1pCuXU8QjwUCd0qdpZ4X6m VIxrDjRUIx5a4AaJGzz66zXEEu5AeQuKgIl8CQ4sGF5gkFNDmuq40qb1bCmp/9qYUGj15u HcDxDKDMSRV11UbZhP8BIvg6OiZmGlE/gst+fNQe5qkAj2J9G2moHlkiNS1sizHOAxV1sl jNDfJPsLBvznVWjlNsrltAII8FnN/70OvWSnYIp3+pwZPjrkqnU5A/rZXW/NTA== 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 4NMHky5PPRzYwy; Tue, 29 Nov 2022 22:56:26 +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 2ATMuQZU097973; Tue, 29 Nov 2022 22:56:26 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 2ATMuQf3097972; Tue, 29 Nov 2022 22:56:26 GMT (envelope-from git) Date: Tue, 29 Nov 2022 22:56:26 GMT Message-Id: <202211292256.2ATMuQf3097972@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: 94395be05c14 - stable/12 - 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/12 X-Git-Reftype: branch X-Git-Commit: 94395be05c14649cfc8e98551be9b2da8535637e Auto-Submitted: auto-generated X-ThisMailContainsUnwantedMimeParts: N The branch stable/12 has been updated by gordon: URL: https://cgit.FreeBSD.org/src/commit/?id=94395be05c14649cfc8e98551be9b2da8535637e commit 94395be05c14649cfc8e98551be9b2da8535637e Author: Tom Jones AuthorDate: 2022-11-17 10:31:38 +0000 Commit: Gordon Tetlow CommitDate: 2022-11-29 22:55:55 +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 79cdd5f78413..eda8bfbd35ea 100644 --- a/sbin/ping/ping.c +++ b/sbin/ping/ping.c @@ -947,6 +947,9 @@ main(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 && @@ -1128,8 +1131,10 @@ 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]; @@ -1139,15 +1144,27 @@ 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) @@ -1159,6 +1176,7 @@ 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 @@ -1288,12 +1306,45 @@ 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) &&