linux/net/mptcp
Davide Caratti 27ab92d999 mptcp: fix length of ADD_ADDR with port sub-option
in current Linux, MPTCP peers advertising endpoints with port numbers use
a sub-option length that wrongly accounts for the trailing TCP NOP. Also,
receivers will only process incoming ADD_ADDR with port having such wrong
sub-option length. Fix this, making ADD_ADDR compliant to RFC8684 §3.4.1.

this can be verified running tcpdump on the kselftests artifacts:

 unpatched kernel:
 [root@bottarga mptcp]# tcpdump -tnnr unpatched.pcap | grep add-addr
 reading from file unpatched.pcap, link-type LINUX_SLL (Linux cooked v1), snapshot length 65535
 IP 10.0.1.1.10000 > 10.0.1.2.53078: Flags [.], ack 101, win 509, options [nop,nop,TS val 214459678 ecr 521312851,mptcp add-addr v1 id 1 a00:201:2774:2d88:7436:85c3:17fd:101], length 0
 IP 10.0.1.2.53078 > 10.0.1.1.10000: Flags [.], ack 101, win 502, options [nop,nop,TS val 521312852 ecr 214459678,mptcp add-addr[bad opt]]

 patched kernel:
 [root@bottarga mptcp]# tcpdump -tnnr patched.pcap | grep add-addr
 reading from file patched.pcap, link-type LINUX_SLL (Linux cooked v1), snapshot length 65535
 IP 10.0.1.1.10000 > 10.0.1.2.38178: Flags [.], ack 101, win 509, options [nop,nop,TS val 3728873902 ecr 2732713192,mptcp add-addr v1 id 1 10.0.2.1:10100 hmac 0xbccdfcbe59292a1f,nop,nop], length 0
 IP 10.0.1.2.38178 > 10.0.1.1.10000: Flags [.], ack 101, win 502, options [nop,nop,TS val 2732713195 ecr 3728873902,mptcp add-addr v1-echo id 1 10.0.2.1:10100,nop,nop], length 0

Fixes: 22fb85ffae ("mptcp: add port support for ADD_ADDR suboption writing")
CC: stable@vger.kernel.org # 5.11+
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Acked-and-tested-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-08 15:02:03 -08:00
..
Kconfig mptcp: depends on IPV6 but not as a module 2020-10-21 08:05:40 -07:00
Makefile mptcp: enable JOIN requests even if cookies are in use 2020-07-31 16:55:32 -07:00
crypto.c crypto: sha - split sha.h into sha1.h and sha2.h 2020-11-20 14:45:33 +11:00
crypto_test.c mptcp: move crypto test to KUNIT 2020-06-26 16:21:39 -07:00
ctrl.c mptcp: add a new sysctl add_addr_timeout 2020-11-04 17:45:53 -08:00
diag.c mptcp: allow dumping subflow context to userspace 2020-03-29 22:14:48 -07:00
mib.c mptcp: add the mibs for ADD_ADDR with port 2021-02-02 18:37:20 -08:00
mib.h mptcp: add the mibs for ADD_ADDR with port 2021-02-02 18:37:20 -08:00
mptcp_diag.c mptcp: add local addr info in mptcp_info 2021-02-15 15:09:14 -08:00
options.c mptcp: fix DATA_FIN generation on early shutdown 2021-02-22 18:54:59 -08:00
pm.c mptcp: add netlink event support 2021-02-12 16:31:46 -08:00
pm_netlink.c mptcp: add local addr info in mptcp_info 2021-02-15 15:09:14 -08:00
protocol.c mptcp: fix missing wakeup 2021-03-04 14:30:13 -08:00
protocol.h mptcp: fix length of ADD_ADDR with port sub-option 2021-03-08 15:02:03 -08:00
subflow.c mptcp: free resources when the port number is mismatched 2021-03-04 14:30:13 -08:00
syncookies.c mptcp: fix syncookie build error on UP 2020-08-01 11:52:55 -07:00
token.c mptcp: token: fix unititialized variable 2020-11-03 13:08:30 -08:00
token_test.c mptcp: introduce token KUNIT self-tests 2020-06-26 16:21:39 -07:00