From nobody Mon Sep 09 19:43:38 2024 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 4X2chV205Pz5TqmR; Mon, 09 Sep 2024 19:43:38 +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 "R11" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4X2chV1FrKz4YPp; Mon, 9 Sep 2024 19:43:38 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1725911018; 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=lwy7VrhY5gb3uUoS7oifigGal88gJoXx7F0SdzElyXE=; b=X8jUFVTiLehHGVqVWlWXAlEcM8Z7TgBkqHqXSdrAJb36G3F4LiqBLHK2YbQe2+nW9xeyHA UZWlGIDxatlUxSpQunws5WZsAoOH6GH9vha5mwrsQw7qPrDCIDojSV+hA/ZxJrvTHwIU91 7ma1VIQn0cnbfoTnVfCfmd3GATnS2RTku4Ytgq3MOfMe1DHDlwV6o6RoJwbshcUbJbUyVY a0GYonYIzu4lAbEKJGwh9FpS2PesQJKCS2VYhJSYlzGvtWs2EYqSGYg14Oi/d5BTiKjodL liUz27Ln7+kqgtXy1k0OL73MwD7vuIGvCWuatihCkltTTncmNX80Cbo6ymoJrA== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1725911018; a=rsa-sha256; cv=none; b=hgBEuaCYUyvhQMjAjbKoEJIz9+q/ntG65TtPYVZsYmxw9Qd4Pl0gzrmiPRc7r1SJqgaewC MFULnYwIgJ3aoEWGpJVkaJOQkEyp7x67Tp1yDOhJle8PV1QWWJ+W0cWefLOa9QJmFf1P7X pD+3JeR0PQnIlL6fuVu4dNFdpL1YlNt8PYDoQKQZ/JPXlmHGYIbLdvvfXHBQcXHTdB2tdI foRwlfjajK2mjlo0UIBCoIeWJMZH/a0rl/xWwukzgpRhuq8J+wv7IBTb2mHx8bCQjAD7nH i5ZHbKsb99agfh5xoaHkGT48tSYHFOFWe2WVyUwUJd8sxKnUWkTiV5s8HC0gZg== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1725911018; 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=lwy7VrhY5gb3uUoS7oifigGal88gJoXx7F0SdzElyXE=; b=L+LdemmPIsymvW0MiP52Tj1gY8PY5KAXzxwlCIyKMuicz7CsK8m2hIMg6319WOHxMDjIPZ 9LFlW+fke7eCkx3MJmI2oy9ipQZPmPxDotRZ4xzBh0KUij1FH2d7cmzB91zXICL1M4nLUG IWPLPHPziteI/Q0y2WPxk3um/tvl7g7vFsFspGFETKGCreNZPifc2TTszUOnIxIT6muyiG Pi0DJGPScX2v0FWph8gCRQOO5Eo8l+3Hi7i75QJUSGWqW+8XVt+BNIynUy4BWbfNB35hdY SzG4/eSM+3NCSgCjO5tXr0Oe/TGh9Flg94jAJ0XFqF+kwiwN6hXmgbbsgzRBzQ== 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 4X2chV0sFjzGpy; Mon, 9 Sep 2024 19:43:38 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.18.1/8.18.1) with ESMTP id 489Jhc1M016209; Mon, 9 Sep 2024 19:43:38 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.18.1/8.18.1/Submit) id 489JhcWx016206; Mon, 9 Sep 2024 19:43:38 GMT (envelope-from git) Date: Mon, 9 Sep 2024 19:43:38 GMT Message-Id: <202409091943.489JhcWx016206@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Joseph Mingrone Subject: git: 508356c03875 - stable/14 - tcpdump: ppp: Use the buffer stack for the de-escaping buffer 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: X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: jrm X-Git-Repository: src X-Git-Refname: refs/heads/stable/14 X-Git-Reftype: branch X-Git-Commit: 508356c038759a9f38e372f1dc1402ef764cb723 Auto-Submitted: auto-generated The branch stable/14 has been updated by jrm: URL: https://cgit.FreeBSD.org/src/commit/?id=508356c038759a9f38e372f1dc1402ef764cb723 commit 508356c038759a9f38e372f1dc1402ef764cb723 Author: Guy Harris AuthorDate: 2024-09-03 17:11:16 +0000 Commit: Joseph Mingrone CommitDate: 2024-09-09 19:38:25 +0000 tcpdump: ppp: Use the buffer stack for the de-escaping buffer This both saves the buffer for freeing later and saves the packet pointer and snapend to be restored when packet processing is complete, even if an exception is thrown with longjmp. This means that the hex/ASCII printing in pretty_print_packet() processes the packet data as captured or read from the savefile, rather than as modified by the PPP printer, so that the bounds checking is correct. That fixes CVE-2024-2397, which was caused by an exception being thrown by the hex/ASCII printer (which should only happen if those routines are called by a packet printer, not if they're called for the -X/-x/-A flag), which jumps back to the setjmp() that surrounds the packet printer. Hilarity^Winfinite looping ensues. Also, restore ndo->ndo_packetp before calling the hex/ASCII printing routine, in case nd_pop_all_packet_info() didn't restore it. Reviewed by: emaste (cherry picked from commit f8860353d4f4c25bacdae5bc1cfb7a95edc9bfe0) --- contrib/tcpdump/print-ppp.c | 31 +++++++++++++++++-------------- contrib/tcpdump/print.c | 8 ++++++-- 2 files changed, 23 insertions(+), 16 deletions(-) diff --git a/contrib/tcpdump/print-ppp.c b/contrib/tcpdump/print-ppp.c index aba243ddb6f2..e5ae0646ebae 100644 --- a/contrib/tcpdump/print-ppp.c +++ b/contrib/tcpdump/print-ppp.c @@ -42,6 +42,8 @@ #include #endif +#include + #include "netdissect.h" #include "extract.h" #include "addrtoname.h" @@ -1363,7 +1365,6 @@ ppp_hdlc(netdissect_options *ndo, u_char *b, *t, c; const u_char *s; u_int i, proto; - const void *sb, *se; if (caplen == 0) return; @@ -1371,9 +1372,11 @@ ppp_hdlc(netdissect_options *ndo, if (length == 0) return; - b = (u_char *)nd_malloc(ndo, caplen); - if (b == NULL) - return; + b = (u_char *)malloc(caplen); + if (b == NULL) { + (*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC, + "%s: malloc", __func__); + } /* * Unescape all the data into a temporary, private, buffer. @@ -1394,13 +1397,15 @@ ppp_hdlc(netdissect_options *ndo, } /* - * Change the end pointer, so bounds checks work. - * Change the pointer to packet data to help debugging. + * Switch to the output buffer for dissection, and save it + * on the buffer stack so it can be freed; our caller must + * pop it when done. */ - sb = ndo->ndo_packetp; - se = ndo->ndo_snapend; - ndo->ndo_packetp = b; - ndo->ndo_snapend = t; + if (!nd_push_buffer(ndo, b, b, (u_int)(t - b))) { + free(b); + (*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC, + "%s: can't push buffer on buffer stack", __func__); + } length = ND_BYTES_AVAILABLE_AFTER(b); /* now lets guess about the payload codepoint format */ @@ -1442,13 +1447,11 @@ ppp_hdlc(netdissect_options *ndo, } cleanup: - ndo->ndo_packetp = sb; - ndo->ndo_snapend = se; + nd_pop_packet_info(ndo); return; trunc: - ndo->ndo_packetp = sb; - ndo->ndo_snapend = se; + nd_pop_packet_info(ndo); nd_print_trunc(ndo); } diff --git a/contrib/tcpdump/print.c b/contrib/tcpdump/print.c index 41a6b524fbf8..96d34b772f08 100644 --- a/contrib/tcpdump/print.c +++ b/contrib/tcpdump/print.c @@ -434,10 +434,14 @@ pretty_print_packet(netdissect_options *ndo, const struct pcap_pkthdr *h, nd_pop_all_packet_info(ndo); /* - * Restore the original snapend, as a printer might have - * changed it. + * Restore the originals snapend and packetp, as a printer + * might have changed them. + * + * XXX - nd_pop_all_packet_info() should have restored the + * original values, but, just in case.... */ ndo->ndo_snapend = sp + h->caplen; + ndo->ndo_packetp = sp; if (ndo->ndo_Xflag) { /* * Print the raw packet data in hex and ASCII.