This patch adds several changes to the ip_defrag selftest, to cover
new IPv6 defrag behavior:
- min IPv6 frag size is now 8 instead of 1280
- new test cases to cover IPv6 defragmentation in nf_conntrack_reasm.c
- new "permissive" mode in negative (overlap) tests: netfilter
sometimes drops invalid packets without passing them to IPv6
underneath, and thus defragmentation sometimes succeeds when
it is expected to fail; so the permissive mode does not fail the
test if the correct reassembled datagram is received instead of a
timeout.
Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit ade446403b ("net: ipv4: do not handle duplicate fragments as
overlapping") changed IPv4 defragmentation so that duplicate fragments,
as well as _some_ fragments completely covered by previously delivered
fragments, do not lead to the whole frag queue being discarded. This
makes the existing ip_defrag selftest flaky.
This patch
* makes sure that negative IPv4 defrag tests generate truly overlapping
fragments that trigger defrag queue drops;
* tests that duplicate IPv4 fragments do not trigger defrag queue drops;
* makes a couple of minor tweaks to the test aimed at increasing its code
coverage and reduce flakiness.
Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Address compiler warning:
ip_defrag.c: In function 'send_udp_frags':
ip_defrag.c:206:16: warning: unused variable 'udphdr' [-Wunused-variable]
struct udphdr udphdr;
^~~~~~
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds ipv6 defragmentation tests to ip_defrag selftest,
to complement existing ipv4 tests.
Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This test creates a raw IPv4 socket, fragments a largish UDP
datagram and sends the fragments out of order.
Then repeats in a loop with different message and fragment lengths.
Then does the same with overlapping fragments (with overlapping
fragments the expectation is that the recv times out).
Tested:
root@<host># time ./ip_defrag.sh
ipv4 defrag
PASS
ipv4 defrag with overlaps
PASS
real 1m7.679s
user 0m0.628s
sys 0m2.242s
A similar test for IPv6 is to follow.
Signed-off-by: Peter Oskolkov <posk@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
