This test verifies whether the encapsulated packets have the correct
configured TTL. It does so by sending ICMP packets through the test
topology and mirroring them to a gretap netdevice. On a busy host
however, more than just the test ICMP packets may end up flowing
through the topology, get mirrored, and counted. This leads to
potential spurious failures as the test observes much more mirrored
packets than the sent test packets, and assumes a bug.
Fix this by tightening up the mirror action match. Change it from
matchall to a flower classifier matching on ICMP packets specifically.
Fixes: 45315673e0 ("selftests: forwarding: Test changes in mirror-to-gretap")
Signed-off-by: Petr Machata <petrm@nvidia.com>
Tested-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from Jakub Kicinski:
"Including fixes from netfilter, wireless and bpf.
Still trending up in size but the good news is that the "current"
regressions are resolved, AFAIK.
We're getting weirdly many fixes for Wake-on-LAN and suspend/resume
handling on embedded this week (most not merged yet), not sure why.
But those are all for older bugs.
Current release - regressions:
- tls: set MSG_SPLICE_PAGES consistently when handing encrypted data
over to TCP
Current release - new code bugs:
- eth: mlx5: correct IDs on VFs internal to the device (IPU)
Previous releases - regressions:
- phy: at803x: fix WoL support / reporting on AR8032
- bonding: fix incorrect deletion of ETH_P_8021AD protocol VID from
slaves, leading to BUG_ON()
- tun: prevent tun_build_skb() from exceeding the packet size limit
- wifi: rtw89: fix 8852AE disconnection caused by RX full flags
- eth/PCI: enetc: fix probing after 6fffbc7ae1 ("PCI: Honor
firmware's device disabled status"), keep PCI devices around even
if they are disabled / not going to be probed to be able to apply
quirks on them
- eth: prestera: fix handling IPv4 routes with nexthop IDs
Previous releases - always broken:
- netfilter: re-work garbage collection to avoid races between
user-facing API and timeouts
- tunnels: fix generating ipv4 PMTU error on non-linear skbs
- nexthop: fix infinite nexthop bucket dump when using maximum
nexthop ID
- wifi: nl80211: fix integer overflow in nl80211_parse_mbssid_elems()
Misc:
- unix: use consistent error code in SO_PEERPIDFD
- ipv6: adjust ndisc_is_useropt() to include PREFIX_INFO, in prep for
upcoming IETF RFC"
* tag 'net-6.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (94 commits)
net: hns3: fix strscpy causing content truncation issue
net: tls: set MSG_SPLICE_PAGES consistently
ibmvnic: Ensure login failure recovery is safe from other resets
ibmvnic: Do partial reset on login failure
ibmvnic: Handle DMA unmapping of login buffs in release functions
ibmvnic: Unmap DMA login rsp buffer on send login fail
ibmvnic: Enforce stronger sanity checks on login response
net: mana: Fix MANA VF unload when hardware is unresponsive
netfilter: nf_tables: remove busy mark and gc batch API
netfilter: nft_set_hash: mark set element as dead when deleting from packet path
netfilter: nf_tables: adapt set backend to use GC transaction API
netfilter: nf_tables: GC transaction API to avoid race with control plane
selftests/bpf: Add sockmap test for redirecting partial skb data
selftests/bpf: fix a CI failure caused by vsock sockmap test
bpf, sockmap: Fix bug that strp_done cannot be called
bpf, sockmap: Fix map type error in sock_map_del_link
xsk: fix refcount underflow in error path
ipv6: adjust ndisc_is_useropt() to also return true for PIO
selftests: forwarding: bridge_mdb: Make test more robust
selftests: forwarding: bridge_mdb_max: Fix failing test with old libnet
...
Martin KaFai Lau says:
====================
pull-request: bpf 2023-08-09
We've added 5 non-merge commits during the last 7 day(s) which contain
a total of 6 files changed, 102 insertions(+), 8 deletions(-).
The main changes are:
1) A bpf sockmap memleak fix and a fix in accessing the programs of
a sockmap under the incorrect map type from Xu Kuohai.
2) A refcount underflow fix in xsk from Magnus Karlsson.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
selftests/bpf: Add sockmap test for redirecting partial skb data
selftests/bpf: fix a CI failure caused by vsock sockmap test
bpf, sockmap: Fix bug that strp_done cannot be called
bpf, sockmap: Fix map type error in sock_map_del_link
xsk: fix refcount underflow in error path
====================
Link: https://lore.kernel.org/r/20230810055303.120917-1-martin.lau@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add a test case to check whether sockmap redirection works correctly
when data length returned by stream_parser is less than skb->len.
In addition, this test checks whether strp_done is called correctly.
The reason is that we returns skb->len - 1 from the stream_parser, so
the last byte in the skb will be held by strp->skb_head. Therefore,
if strp_done is not called to free strp->skb_head, we'll get a memleak
warning.
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Link: https://lore.kernel.org/r/20230804073740.194770-5-xukuohai@huaweicloud.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
BPF CI has reported the following failure:
Error: #200/79 sockmap_listen/sockmap VSOCK test_vsock_redir
Error: #200/79 sockmap_listen/sockmap VSOCK test_vsock_redir
./test_progs:vsock_unix_redir_connectible:1506: egress: write: Transport endpoint is not connected
vsock_unix_redir_connectible:FAIL:1506
./test_progs:vsock_unix_redir_connectible:1506: ingress: write: Transport endpoint is not connected
vsock_unix_redir_connectible:FAIL:1506
./test_progs:vsock_unix_redir_connectible:1506: egress: write: Transport endpoint is not connected
vsock_unix_redir_connectible:FAIL:1506
./test_progs:vsock_unix_redir_connectible:1514: ingress: recv() err, errno=11
vsock_unix_redir_connectible:FAIL:1514
./test_progs:vsock_unix_redir_connectible:1518: ingress: vsock socket map failed, a != b
vsock_unix_redir_connectible:FAIL:1518
./test_progs:vsock_unix_redir_connectible:1525: ingress: want pass count 1, have 0
It’s because the recv(... MSG_DONTWAIT) syscall in the test case is
called before the queued work sk_psock_backlog() in the kernel finishes
executing. So the data to be read is still queued in psock->ingress_skb
and cannot be read by the user program. Therefore, the non-blocking
recv() reads nothing and reports an EAGAIN error.
So replace recv(... MSG_DONTWAIT) with xrecv_nonblock(), which calls
select() to wait for data to be readable or timeout before calls recv().
Fixes: d61bd8c1fd ("selftests/bpf: add a test case for vsock sockmap")
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Link: https://lore.kernel.org/r/20230804073740.194770-4-xukuohai@huaweicloud.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
The test installs filters that match on various IP fragments (e.g., no
fragment, first fragment) and expects a certain amount of packets to hit
each filter. This is problematic as the filters are not specific enough
and can match IP packets (e.g., IGMP) generated by the stack, resulting
in failures [1].
Fix by making the filters more specific and match on more fields in the
IP header: Source IP, destination IP and protocol.
[1]
# timeout set to 0
# selftests: net/forwarding: tc_tunnel_key.sh
# TEST: tunnel_key nofrag (skip_hw) [FAIL]
# packet smaller than MTU was not tunneled
# INFO: Could not test offloaded functionality
not ok 89 selftests: net/forwarding: tc_tunnel_key.sh # exit=1
Fixes: 533a89b194 ("selftests: forwarding: add tunnel_key "nofrag" test case")
Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Closes: https://lore.kernel.org/netdev/adc5e40d-d040-a65e-eb26-edf47dac5b02@alu.unizg.hr/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Tested-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Acked-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20230808141503.4060661-14-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The test relies on 'nc' being the netcat version from the nmap project.
While this seems to be the case on Fedora, it is not the case on Ubuntu,
resulting in failures such as [1].
Fix by explicitly using the 'ncat' utility from the nmap project and the
skip the test in case it is not installed.
[1]
# timeout set to 0
# selftests: net/forwarding: tc_actions.sh
# TEST: gact drop and ok (skip_hw) [ OK ]
# TEST: mirred egress flower redirect (skip_hw) [ OK ]
# TEST: mirred egress flower mirror (skip_hw) [ OK ]
# TEST: mirred egress matchall mirror (skip_hw) [ OK ]
# TEST: mirred_egress_to_ingress (skip_hw) [ OK ]
# nc: invalid option -- '-'
# usage: nc [-46CDdFhklNnrStUuvZz] [-I length] [-i interval] [-M ttl]
# [-m minttl] [-O length] [-P proxy_username] [-p source_port]
# [-q seconds] [-s sourceaddr] [-T keyword] [-V rtable] [-W recvlimit]
# [-w timeout] [-X proxy_protocol] [-x proxy_address[:port]]
# [destination] [port]
# nc: invalid option -- '-'
# usage: nc [-46CDdFhklNnrStUuvZz] [-I length] [-i interval] [-M ttl]
# [-m minttl] [-O length] [-P proxy_username] [-p source_port]
# [-q seconds] [-s sourceaddr] [-T keyword] [-V rtable] [-W recvlimit]
# [-w timeout] [-X proxy_protocol] [-x proxy_address[:port]]
# [destination] [port]
# TEST: mirred_egress_to_ingress_tcp (skip_hw) [FAIL]
# server output check failed
# INFO: Could not test offloaded functionality
not ok 80 selftests: net/forwarding: tc_actions.sh # exit=1
Fixes: ca22da2fbd ("act_mirred: use the backlog for nested calls to mirred ingress")
Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Closes: https://lore.kernel.org/netdev/adc5e40d-d040-a65e-eb26-edf47dac5b02@alu.unizg.hr/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Tested-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20230808141503.4060661-12-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The selftest relies on iproute2 changes present in version 6.3, but the
test does not check for it, resulting in error:
# ./bridge_mdb.sh
INFO: # Host entries configuration tests
TEST: Common host entries configuration tests (IPv4) [FAIL]
Managed to add IPv4 host entry with a filter mode
TEST: Common host entries configuration tests (IPv6) [FAIL]
Managed to add IPv6 host entry with a filter mode
TEST: Common host entries configuration tests (L2) [FAIL]
Managed to add L2 host entry with a filter mode
INFO: # Port group entries configuration tests - (*, G)
Command "replace" is unknown, try "bridge mdb help".
[...]
Fix by skipping the test if iproute2 is too old.
Fixes: b6d00da086 ("selftests: forwarding: Add bridge MDB test")
Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Closes: https://lore.kernel.org/netdev/6b04b2ba-2372-6f6b-3ac8-b7cba1cfae83@alu.unizg.hr/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Tested-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20230808141503.4060661-4-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The default timeout for selftests is 45 seconds, but it is not enough
for forwarding selftests which can takes minutes to finish depending on
the number of tests cases:
# make -C tools/testing/selftests TARGETS=net/forwarding run_tests
TAP version 13
1..102
# timeout set to 45
# selftests: net/forwarding: bridge_igmp.sh
# TEST: IGMPv2 report 239.10.10.10 [ OK ]
# TEST: IGMPv2 leave 239.10.10.10 [ OK ]
# TEST: IGMPv3 report 239.10.10.10 is_include [ OK ]
# TEST: IGMPv3 report 239.10.10.10 include -> allow [ OK ]
#
not ok 1 selftests: net/forwarding: bridge_igmp.sh # TIMEOUT 45 seconds
Fix by switching off the timeout and setting it to 0. A similar change
was done for BPF selftests in commit 6fc5916cc2 ("selftests: bpf:
Switch off timeout").
Fixes: 81573b18f2 ("selftests/net/forwarding: add Makefile to install tests")
Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Closes: https://lore.kernel.org/netdev/8d149f8c-818e-d141-a0ce-a6bae606bc22@alu.unizg.hr/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Tested-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20230808141503.4060661-3-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As explained in [1], the forwarding selftests are meant to be run with
either physical loopbacks or veth pairs. The interfaces are expected to
be specified in a user-provided forwarding.config file or as command
line arguments. By default, this file is not present and the tests fail:
# make -C tools/testing/selftests TARGETS=net/forwarding run_tests
[...]
TAP version 13
1..102
# timeout set to 45
# selftests: net/forwarding: bridge_igmp.sh
# Command line is not complete. Try option "help"
# Failed to create netif
not ok 1 selftests: net/forwarding: bridge_igmp.sh # exit=1
[...]
Fix by skipping a test if interfaces are not provided either via the
configuration file or command line arguments.
# make -C tools/testing/selftests TARGETS=net/forwarding run_tests
[...]
TAP version 13
1..102
# timeout set to 45
# selftests: net/forwarding: bridge_igmp.sh
# SKIP: Cannot create interface. Name not specified
ok 1 selftests: net/forwarding: bridge_igmp.sh # SKIP
[1] tools/testing/selftests/net/forwarding/README
Fixes: 81573b18f2 ("selftests/net/forwarding: add Makefile to install tests")
Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Closes: https://lore.kernel.org/netdev/856d454e-f83c-20cf-e166-6dc06cbc1543@alu.unizg.hr/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Tested-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20230808141503.4060661-2-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
A netlink dump callback can return a positive number to signal that more
information needs to be dumped or zero to signal that the dump is
complete. In the second case, the core netlink code will append the
NLMSG_DONE message to the skb in order to indicate to user space that
the dump is complete.
The nexthop bucket dump callback always returns a positive number if
nexthop buckets were filled in the provided skb, even if the dump is
complete. This means that a dump will span at least two recvmsg() calls
as long as nexthop buckets are present. In the last recvmsg() call the
dump callback will not fill in any nexthop buckets because the previous
call indicated that the dump should restart from the last dumped nexthop
ID plus one.
# ip link add name dummy1 up type dummy
# ip nexthop add id 1 dev dummy1
# ip nexthop add id 10 group 1 type resilient buckets 2
# strace -e sendto,recvmsg -s 5 ip nexthop bucket
sendto(3, [[{nlmsg_len=24, nlmsg_type=RTM_GETNEXTHOPBUCKET, nlmsg_flags=NLM_F_REQUEST|NLM_F_DUMP, nlmsg_seq=1691396980, nlmsg_pid=0}, {family=AF_UNSPEC, data="\x00\x00\x00\x00\x00"...}], {nlmsg_len=0, nlmsg_type=0 /* NLMSG_??? */, nlmsg_flags=0, nlmsg_seq=0, nlmsg_pid=0}], 152, 0, NULL, 0) = 152
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=NULL, iov_len=0}], msg_iovlen=1, msg_controllen=0, msg_flags=MSG_TRUNC}, MSG_PEEK|MSG_TRUNC) = 128
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=[[{nlmsg_len=64, nlmsg_type=RTM_NEWNEXTHOPBUCKET, nlmsg_flags=NLM_F_MULTI, nlmsg_seq=1691396980, nlmsg_pid=347}, {family=AF_UNSPEC, data="\x00\x00\x00\x00\x00"...}], [{nlmsg_len=64, nlmsg_type=RTM_NEWNEXTHOPBUCKET, nlmsg_flags=NLM_F_MULTI, nlmsg_seq=1691396980, nlmsg_pid=347}, {family=AF_UNSPEC, data="\x00\x00\x00\x00\x00"...}]], iov_len=32768}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 128
id 10 index 0 idle_time 6.66 nhid 1
id 10 index 1 idle_time 6.66 nhid 1
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=NULL, iov_len=0}], msg_iovlen=1, msg_controllen=0, msg_flags=MSG_TRUNC}, MSG_PEEK|MSG_TRUNC) = 20
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=[{nlmsg_len=20, nlmsg_type=NLMSG_DONE, nlmsg_flags=NLM_F_MULTI, nlmsg_seq=1691396980, nlmsg_pid=347}, 0], iov_len=32768}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 20
+++ exited with 0 +++
This behavior is both inefficient and buggy. If the last nexthop to be
dumped had the maximum ID of 0xffffffff, then the dump will restart from
0 (0xffffffff + 1) and never end:
# ip link add name dummy1 up type dummy
# ip nexthop add id 1 dev dummy1
# ip nexthop add id $((2**32-1)) group 1 type resilient buckets 2
# ip nexthop bucket
id 4294967295 index 0 idle_time 5.55 nhid 1
id 4294967295 index 1 idle_time 5.55 nhid 1
id 4294967295 index 0 idle_time 5.55 nhid 1
id 4294967295 index 1 idle_time 5.55 nhid 1
[...]
Fix by adjusting the dump callback to return zero when the dump is
complete. After the fix only one recvmsg() call is made and the
NLMSG_DONE message is appended to the RTM_NEWNEXTHOPBUCKET responses:
# ip link add name dummy1 up type dummy
# ip nexthop add id 1 dev dummy1
# ip nexthop add id $((2**32-1)) group 1 type resilient buckets 2
# strace -e sendto,recvmsg -s 5 ip nexthop bucket
sendto(3, [[{nlmsg_len=24, nlmsg_type=RTM_GETNEXTHOPBUCKET, nlmsg_flags=NLM_F_REQUEST|NLM_F_DUMP, nlmsg_seq=1691396737, nlmsg_pid=0}, {family=AF_UNSPEC, data="\x00\x00\x00\x00\x00"...}], {nlmsg_len=0, nlmsg_type=0 /* NLMSG_??? */, nlmsg_flags=0, nlmsg_seq=0, nlmsg_pid=0}], 152, 0, NULL, 0) = 152
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=NULL, iov_len=0}], msg_iovlen=1, msg_controllen=0, msg_flags=MSG_TRUNC}, MSG_PEEK|MSG_TRUNC) = 148
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=[[{nlmsg_len=64, nlmsg_type=RTM_NEWNEXTHOPBUCKET, nlmsg_flags=NLM_F_MULTI, nlmsg_seq=1691396737, nlmsg_pid=350}, {family=AF_UNSPEC, data="\x00\x00\x00\x00\x00"...}], [{nlmsg_len=64, nlmsg_type=RTM_NEWNEXTHOPBUCKET, nlmsg_flags=NLM_F_MULTI, nlmsg_seq=1691396737, nlmsg_pid=350}, {family=AF_UNSPEC, data="\x00\x00\x00\x00\x00"...}], [{nlmsg_len=20, nlmsg_type=NLMSG_DONE, nlmsg_flags=NLM_F_MULTI, nlmsg_seq=1691396737, nlmsg_pid=350}, 0]], iov_len=32768}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 148
id 4294967295 index 0 idle_time 6.61 nhid 1
id 4294967295 index 1 idle_time 6.61 nhid 1
+++ exited with 0 +++
Note that if the NLMSG_DONE message cannot be appended because of size
limitations, then another recvmsg() will be needed, but the core netlink
code will not invoke the dump callback and simply reply with a
NLMSG_DONE message since it knows that the callback previously returned
zero.
Add a test that fails before the fix:
# ./fib_nexthops.sh -t basic_res
[...]
TEST: Maximum nexthop ID dump [FAIL]
[...]
And passes after it:
# ./fib_nexthops.sh -t basic_res
[...]
TEST: Maximum nexthop ID dump [ OK ]
[...]
Fixes: 8a1bbabb03 ("nexthop: Add netlink handlers for bucket dump")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230808075233.3337922-4-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
A netlink dump callback can return a positive number to signal that more
information needs to be dumped or zero to signal that the dump is
complete. In the second case, the core netlink code will append the
NLMSG_DONE message to the skb in order to indicate to user space that
the dump is complete.
The nexthop dump callback always returns a positive number if nexthops
were filled in the provided skb, even if the dump is complete. This
means that a dump will span at least two recvmsg() calls as long as
nexthops are present. In the last recvmsg() call the dump callback will
not fill in any nexthops because the previous call indicated that the
dump should restart from the last dumped nexthop ID plus one.
# ip nexthop add id 1 blackhole
# strace -e sendto,recvmsg -s 5 ip nexthop
sendto(3, [[{nlmsg_len=24, nlmsg_type=RTM_GETNEXTHOP, nlmsg_flags=NLM_F_REQUEST|NLM_F_DUMP, nlmsg_seq=1691394315, nlmsg_pid=0}, {nh_family=AF_UNSPEC, nh_scope=RT_SCOPE_UNIVERSE, nh_protocol=RTPROT_UNSPEC, nh_flags=0}], {nlmsg_len=0, nlmsg_type=0 /* NLMSG_??? */, nlmsg_flags=0, nlmsg_seq=0, nlmsg_pid=0}], 152, 0, NULL, 0) = 152
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=NULL, iov_len=0}], msg_iovlen=1, msg_controllen=0, msg_flags=MSG_TRUNC}, MSG_PEEK|MSG_TRUNC) = 36
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=[{nlmsg_len=36, nlmsg_type=RTM_NEWNEXTHOP, nlmsg_flags=NLM_F_MULTI, nlmsg_seq=1691394315, nlmsg_pid=343}, {nh_family=AF_INET, nh_scope=RT_SCOPE_UNIVERSE, nh_protocol=RTPROT_UNSPEC, nh_flags=0}, [[{nla_len=8, nla_type=NHA_ID}, 1], {nla_len=4, nla_type=NHA_BLACKHOLE}]], iov_len=32768}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 36
id 1 blackhole
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=NULL, iov_len=0}], msg_iovlen=1, msg_controllen=0, msg_flags=MSG_TRUNC}, MSG_PEEK|MSG_TRUNC) = 20
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=[{nlmsg_len=20, nlmsg_type=NLMSG_DONE, nlmsg_flags=NLM_F_MULTI, nlmsg_seq=1691394315, nlmsg_pid=343}, 0], iov_len=32768}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 20
+++ exited with 0 +++
This behavior is both inefficient and buggy. If the last nexthop to be
dumped had the maximum ID of 0xffffffff, then the dump will restart from
0 (0xffffffff + 1) and never end:
# ip nexthop add id $((2**32-1)) blackhole
# ip nexthop
id 4294967295 blackhole
id 4294967295 blackhole
[...]
Fix by adjusting the dump callback to return zero when the dump is
complete. After the fix only one recvmsg() call is made and the
NLMSG_DONE message is appended to the RTM_NEWNEXTHOP response:
# ip nexthop add id $((2**32-1)) blackhole
# strace -e sendto,recvmsg -s 5 ip nexthop
sendto(3, [[{nlmsg_len=24, nlmsg_type=RTM_GETNEXTHOP, nlmsg_flags=NLM_F_REQUEST|NLM_F_DUMP, nlmsg_seq=1691394080, nlmsg_pid=0}, {nh_family=AF_UNSPEC, nh_scope=RT_SCOPE_UNIVERSE, nh_protocol=RTPROT_UNSPEC, nh_flags=0}], {nlmsg_len=0, nlmsg_type=0 /* NLMSG_??? */, nlmsg_flags=0, nlmsg_seq=0, nlmsg_pid=0}], 152, 0, NULL, 0) = 152
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=NULL, iov_len=0}], msg_iovlen=1, msg_controllen=0, msg_flags=MSG_TRUNC}, MSG_PEEK|MSG_TRUNC) = 56
recvmsg(3, {msg_name={sa_family=AF_NETLINK, nl_pid=0, nl_groups=00000000}, msg_namelen=12, msg_iov=[{iov_base=[[{nlmsg_len=36, nlmsg_type=RTM_NEWNEXTHOP, nlmsg_flags=NLM_F_MULTI, nlmsg_seq=1691394080, nlmsg_pid=342}, {nh_family=AF_INET, nh_scope=RT_SCOPE_UNIVERSE, nh_protocol=RTPROT_UNSPEC, nh_flags=0}, [[{nla_len=8, nla_type=NHA_ID}, 4294967295], {nla_len=4, nla_type=NHA_BLACKHOLE}]], [{nlmsg_len=20, nlmsg_type=NLMSG_DONE, nlmsg_flags=NLM_F_MULTI, nlmsg_seq=1691394080, nlmsg_pid=342}, 0]], iov_len=32768}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 56
id 4294967295 blackhole
+++ exited with 0 +++
Note that if the NLMSG_DONE message cannot be appended because of size
limitations, then another recvmsg() will be needed, but the core netlink
code will not invoke the dump callback and simply reply with a
NLMSG_DONE message since it knows that the callback previously returned
zero.
Add a test that fails before the fix:
# ./fib_nexthops.sh -t basic
[...]
TEST: Maximum nexthop ID dump [FAIL]
[...]
And passes after it:
# ./fib_nexthops.sh -t basic
[...]
TEST: Maximum nexthop ID dump [ OK ]
[...]
Fixes: ab84be7e54 ("net: Initial nexthop code")
Reported-by: Petr Machata <petrm@nvidia.com>
Closes: https://lore.kernel.org/netdev/87sf91enuf.fsf@nvidia.com/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230808075233.3337922-2-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull kvm fixes from Paolo Bonzini:
"x86:
- Fix SEV race condition
ARM:
- Fixes for the configuration of SVE/SME traps when hVHE mode is in
use
- Allow use of pKVM on systems with FF-A implementations that are
v1.0 compatible
- Request/release percpu IRQs (arch timer, vGIC maintenance)
correctly when pKVM is in use
- Fix function prototype after __kvm_host_psci_cpu_entry() rename
- Skip to the next instruction when emulating writes to TCR_EL1 on
AmpereOne systems
Selftests:
- Fix missing include"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
selftests/rseq: Fix build with undefined __weak
KVM: SEV: remove ghcb variable declarations
KVM: SEV: only access GHCB fields once
KVM: SEV: snapshot the GHCB before accessing it
KVM: arm64: Skip instruction after emulating write to TCR_EL1
KVM: arm64: fix __kvm_host_psci_cpu_entry() prototype
KVM: arm64: Fix resetting SME trap values on reset for (h)VHE
KVM: arm64: Fix resetting SVE trap values on reset for hVHE
KVM: arm64: Use the appropriate feature trap register when activating traps
KVM: arm64: Helper to write to appropriate feature trap register based on mode
KVM: arm64: Disable SME traps for (h)VHE at setup
KVM: arm64: Use the appropriate feature trap register for SVE at EL2 setup
KVM: arm64: Factor out code for checking (h)VHE mode into a macro
KVM: arm64: Rephrase percpu enable/disable tracking in terms of hyp
KVM: arm64: Fix hardware enable/disable flows for pKVM
KVM: arm64: Allow pKVM on v1.0 compatible FF-A implementations
