selftests: cmsg_ipv6: repeat the exact packet

cmsg_ipv6 test requests tcpdump to capture 4 packets,
and sends until tcpdump quits. Only the first packet
is "real", however, and the rest are basic UDP packets.
So if tcpdump doesn't start in time it will miss
the real packet and only capture the UDP ones.

This makes the test fail on slow machine (no KVM or with
debug enabled) 100% of the time, while it passes in fast
environments.

Repeat the "real" / expected packet.

Fixes: 9657ad09e1fa ("selftests: net: test IPV6_TCLASS")
Fixes: 05ae83d5a4a2 ("selftests: net: test IPV6_HOPLIMIT")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests/net: convert cmsg tests to make them run in unique namespace

Here is the test result after conversion.

]# ./cmsg_ipv6.sh
OK
]# ./cmsg_so_mark.sh
OK
]# ./cmsg_time.sh
OK

Acked-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

selftest: net: Improve IPV6_TCLASS/IPV6_HOPLIMIT tests apparmor compatibility

"tcpdump" is used to capture traffic in these tests while using a random,
temporary and not suffixed file for it. This can interfere with apparmor
configuration where the tool is only allowed to read from files with
'known' extensions.

The MINE type application/vnd.tcpdump.pcap was registered with IANA for
pcap files and .pcap is the extension that is both most common but also
aligned with standard apparmor configurations. See TCPDUMP(8) for more
details.

This improves compatibility with standard apparmor configurations by
using ".pcap" as the file extension for the tests' temporary files.

Signed-off-by: Andrei Gherzan <andrei.gherzan@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: net: basic test for IPV6_2292*

Add a basic test to make sure ping sockets don't crash
with IPV6_2292* options.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: net: test IPV6_HOPLIMIT

Test setting IPV6_HOPLIMIT via setsockopt and cmsg
across socket types.

Output without the kernel support (this series):

Case HOPLIMIT ICMP cmsg - packet data returned 1, expected 0
Case HOPLIMIT ICMP diff - packet data returned 1, expected 0

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: net: test IPV6_TCLASS

Test setting IPV6_TCLASS via setsockopt and cmsg
across socket types.

Output without the kernel support (this series):

Case TCLASS ICMP cmsg - packet data returned 1, expected 0
Case TCLASS ICMP cmsg - rejection returned 0, expected 1
Case TCLASS ICMP diff - pass returned 1, expected 0
Case TCLASS ICMP diff - packet data returned 1, expected 0
Case TCLASS ICMP diff - rejection returned 0, expected 1

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: net: test IPV6_DONTFRAG

Test setting IPV6_DONTFRAG via setsockopt and cmsg
across socket types.

Output without the kernel support (this series):

Case DONTFRAG ICMP setsock returned 0, expected 1
Case DONTFRAG ICMP cmsg returned 0, expected 1
Case DONTFRAG ICMP both returned 0, expected 1
Case DONTFRAG ICMP diff returned 0, expected 1
FAIL - 4/24 cases failed

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>