git: 225e85513fd7 - main - pf tests: test IPv6 fragmentation with link-local addresses

From: Kristof Provost <kp_at_FreeBSD.org>
Date: Thu, 16 Mar 2023 10:01:26 UTC
The branch main has been updated by kp:

URL: https://cgit.FreeBSD.org/src/commit/?id=225e85513fd7a5e31f649e35f0b99454bb725776

commit 225e85513fd7a5e31f649e35f0b99454bb725776
Author:     Kristof Provost <kp@FreeBSD.org>
AuthorDate: 2023-03-12 15:08:31 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2023-03-16 09:59:04 +0000

    pf tests: test IPv6 fragmentation with link-local addresses
    
    We've observed a panic after pf_refragment6() with link-local addresses,
    because pf_refragment6() calls ip6_forward() even for a simple output
    case.
    That results in us entering ip6_forward() with an mbuf with a NULL
    m->m_pkthdr.rcvif, which can cause a NULL deref (but seemingly not for
    GUAs.
    
    Test sending fragmented link-local packets to pf.
    
    MFC after:      3 days
    Sponsored by:   Rubicon Communications, LLC ("Netgate")
    Differential Revision:  https://reviews.freebsd.org/D39063
---
 tests/sys/netpfil/pf/fragmentation.sh | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/tests/sys/netpfil/pf/fragmentation.sh b/tests/sys/netpfil/pf/fragmentation.sh
index 03ba5030d8aa..554a9fdecc09 100644
--- a/tests/sys/netpfil/pf/fragmentation.sh
+++ b/tests/sys/netpfil/pf/fragmentation.sh
@@ -103,6 +103,10 @@ v6_body()
 	jexec singsing ifconfig ${epair_link}b inet6 -ifdisabled
 	ifconfig ${epair_send}a inet6 -ifdisabled
 
+	ifconfig ${epair_send}a
+	jexec alcatraz ifconfig ${epair_send}b
+	lladdr=$(jexec alcatraz ifconfig ${epair_send}b | awk '/ scopeid / { print($2); }' | cut -f 1 -d %)
+
 	jexec alcatraz pfctl -e
 	pft_set_rules alcatraz \
 		"scrub fragment reassemble" \
@@ -120,6 +124,12 @@ v6_body()
 	atf_check -s exit:0 -o ignore\
 		ping -6 -c 1 -b 70000 -s 65000 2001:db8:42::2
 
+	# Force an NDP lookup
+	ping -6 -c 1 ${lladdr}%${epair_send}a
+
+	atf_check -s exit:0 -o ignore\
+		ping -6 -c 1 -b 70000 -s 65000 ${lladdr}%${epair_send}a
+
 	# Forwarding test
 	atf_check -s exit:0 -o ignore \
 		ping -6 -c 1 2001:db8:43::3