Date: Wed, 29 Apr 2026 14:50:20 +0000 From: Mark Johnston <markj@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org Cc: Kristof Provost <kp@FreeBSD.org> Subject: git: 0ab05345fb40 - releng/13.5 - pf: improve SCTP validation Message-ID: <69f21aac.3dd2a.6db6d759@gitrepo.freebsd.org>
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The branch releng/13.5 has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=0ab05345fb408b70f37a6b1c522ef3e084fc5f58 commit 0ab05345fb408b70f37a6b1c522ef3e084fc5f58 Author: Kristof Provost <kp@FreeBSD.org> AuthorDate: 2026-04-26 09:34:55 +0000 Commit: Mark Johnston <markj@FreeBSD.org> CommitDate: 2026-04-28 20:32:11 +0000 pf: improve SCTP validation As per RFC5061 "4.2. New Parameter Types" the add/delete IP address parameters (0xc001, 0xc002) may not be present in an INIT or INIT-ACK chunk. They are only allowed to be present in an ASCONF chunk. This also prevents unbounded recursion while parsing an SCTP packet. Approved by: so Security: FreeBSD-SA-26:14.pf Security: CVE-2026-7164 PR: 294799 Reported by: Igor Gabriel Sousa e Souza MFC after: 3 days Sponsored by: Orange Business Services --- sys/netpfil/pf/pf.c | 18 +++++++++++++----- tests/sys/netpfil/pf/sctp.py | 43 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 56 insertions(+), 5 deletions(-) diff --git a/sys/netpfil/pf/pf.c b/sys/netpfil/pf/pf.c index b5f872d40b02..cf077e001ae9 100644 --- a/sys/netpfil/pf/pf.c +++ b/sys/netpfil/pf/pf.c @@ -5925,7 +5925,7 @@ again: static int pf_multihome_scan(struct mbuf *m, int start, int len, struct pf_pdesc *pd, - struct pfi_kkif *kif, int op) + struct pfi_kkif *kif, int op, bool asconf) { int off = 0; struct pf_sctp_multihome_job *job; @@ -6019,13 +6019,16 @@ pf_multihome_scan(struct mbuf *m, int start, int len, struct pf_pdesc *pd, int ret; struct sctp_asconf_paramhdr ah; + if (asconf) + return (PF_DROP); + if (!pf_pull_hdr(m, start + off, &ah, sizeof(ah), NULL, NULL, pd->af)) return (PF_DROP); ret = pf_multihome_scan(m, start + off + sizeof(ah), ntohs(ah.ph.param_length) - sizeof(ah), pd, kif, - SCTP_ADD_IP_ADDRESS); + SCTP_ADD_IP_ADDRESS, true); if (ret != PF_PASS) return (ret); break; @@ -6034,12 +6037,15 @@ pf_multihome_scan(struct mbuf *m, int start, int len, struct pf_pdesc *pd, int ret; struct sctp_asconf_paramhdr ah; + if (asconf) + return (PF_DROP); + if (!pf_pull_hdr(m, start + off, &ah, sizeof(ah), NULL, NULL, pd->af)) return (PF_DROP); ret = pf_multihome_scan(m, start + off + sizeof(ah), ntohs(ah.ph.param_length) - sizeof(ah), pd, kif, - SCTP_DEL_IP_ADDRESS); + SCTP_DEL_IP_ADDRESS, true); if (ret != PF_PASS) return (ret); break; @@ -6061,7 +6067,8 @@ pf_multihome_scan_init(struct mbuf *m, int start, int len, struct pf_pdesc *pd, start += sizeof(struct sctp_init_chunk); len -= sizeof(struct sctp_init_chunk); - return (pf_multihome_scan(m, start, len, pd, kif, SCTP_ADD_IP_ADDRESS)); + return (pf_multihome_scan(m, start, len, pd, kif, SCTP_ADD_IP_ADDRESS, + false)); } int @@ -6071,7 +6078,8 @@ pf_multihome_scan_asconf(struct mbuf *m, int start, int len, start += sizeof(struct sctp_asconf_chunk); len -= sizeof(struct sctp_asconf_chunk); - return (pf_multihome_scan(m, start, len, pd, kif, SCTP_ADD_IP_ADDRESS)); + return (pf_multihome_scan(m, start, len, pd, kif, SCTP_ADD_IP_ADDRESS, + false)); } int diff --git a/tests/sys/netpfil/pf/sctp.py b/tests/sys/netpfil/pf/sctp.py index 38bb9f2dff74..7cf88c969d48 100644 --- a/tests/sys/netpfil/pf/sctp.py +++ b/tests/sys/netpfil/pf/sctp.py @@ -426,6 +426,49 @@ class TestSCTP(VnetTestTemplate): assert re.search(r"all sctp 192.0.2.4:.*192.0.2.3:1234", states) assert re.search(r"all sctp 192.0.2.4:.*192.0.2.2:1234", states) +class TestSCTP_SRV(VnetTestTemplate): + REQUIRED_MODULES = ["sctp", "pf"] + TOPOLOGY = { + "vnet1": {"ifaces": ["if1"]}, + "vnet2": {"ifaces": ["if1"]}, + "if1": {"prefixes4": [("192.0.2.1/24", "192.0.2.2/24")]}, + } + + def vnet2_handler(self, vnet): + ToolsHelper.print_output("/sbin/pfctl -e") + ToolsHelper.pf_rules([ + "set state-policy if-bound", + "pass inet proto sctp", + "pass on lo"]) + + # Start an SCTP server process, pipe the ppid + data back to the other vnet? + srv = SCTPServer(socket.AF_INET, port=1234) + while True: + srv.accept(vnet) + + @pytest.mark.require_user("root") + @pytest.mark.require_progs(["scapy"]) + def test_too_many_add_ip(self): + import scapy.all as sp + DEPTH=90 + params=[] + for i in range(0, DEPTH): + ch = sp.SCTPChunkParamAddIPAddr(len=(DEPTH - i) * 8) + params.append(ch) + packet = sp.IP(src="192.0.2.1", dst="192.0.2.2") \ + / sp.SCTP(sport=4321, dport=1234) \ + / sp.SCTPChunkInit(init_tag=1, n_in_streams=1, n_out_streams=1, a_rwnd=1500, + params=params) + packet.show() + sp.hexdump(packet) + print("len %d" % len(packet)) + + r = sp.sr1(packet, timeout=3) + # We should not get a reply to this + if r: + r.show() + assert not r + class TestSCTPv6(VnetTestTemplate): REQUIRED_MODULES = ["sctp", "pf"] TOPOLOGY = {home | help
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