linux-dev/net/mptcp/subflow.c, branch linus/master

mptcp: Check for orphaned subflow before handling MP_FAIL timer

2022-05-20T03:05:07Z

MP_FAIL timeout (waiting for a peer to respond to an MP_FAIL with another MP_FAIL) is implemented using the MPTCP socket's sk_timer. That timer is also used at MPTCP socket close, so it's important to not have the two timer users interfere with each other. At MPTCP socket close, all subflows are orphaned before sk_timer is manipulated. By checking the SOCK_DEAD flag on the subflows, each subflow can determine if the timer is safe to alter without acquiring any MPTCP-level lock. This replaces code that was using the mptcp_data_lock and MPTCP-level socket state checks that did not correctly protect the timer. Fixes: 49fa1919d6bc ("mptcp: reset subflow when MP_FAIL doesn't respond") Reviewed-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: Jakub Kicinski

mptcp: stop using the mptcp_has_another_subflow() helper

2022-05-20T03:05:07Z

The mentioned helper requires the msk socket lock, and the current callers don't own it nor can't acquire it, so the access is racy. All the current callers are really checking for infinite mapping fallback, and the latter condition is explicitly tracked by the relevant msk variable: we can safely remove the caller usage - and the caller itself. The issue is present since MP_FAIL implementation, but the fix only applies since the infinite fallback support, ence the somewhat unexpected fixes tag. Fixes: 0530020a7c8f ("mptcp: track and update contiguous data status") Acked-and-tested-by: Geliang Tang Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2022-05-19T18:23:59Z

drivers/net/ethernet/mellanox/mlx5/core/main.c b33886971dbc ("net/mlx5: Initialize flow steering during driver probe") 40379a0084c2 ("net/mlx5_fpga: Drop INNOVA TLS support") f2b41b32cde8 ("net/mlx5: Remove ipsec_ops function table") https://lore.kernel.org/all/20220519040345.6yrjromcdistu7vh@sx1/ 16d42d313350 ("net/mlx5: Drain fw_reset when removing device") 8324a02c342a ("net/mlx5: Add exit route when waiting for FW") https://lore.kernel.org/all/20220519114119.060ce014@canb.auug.org.au/ tools/testing/selftests/net/mptcp/mptcp_join.sh e274f7154008 ("selftests: mptcp: add subflow limits test-cases") b6e074e171bc ("selftests: mptcp: add infinite map testcase") 5ac1d2d63451 ("selftests: mptcp: Add tests for userspace PM type") https://lore.kernel.org/all/20220516111918.366d747f@canb.auug.org.au/ net/mptcp/options.c ba2c89e0ea74 ("mptcp: fix checksum byte order") 1e39e5a32ad7 ("mptcp: infinite mapping sending") ea66758c1795 ("tcp: allow MPTCP to update the announced window") https://lore.kernel.org/all/20220519115146.751c3a37@canb.auug.org.au/ net/mptcp/pm.c 95d686517884 ("mptcp: fix subflow accounting on close") 4d25247d3ae4 ("mptcp: bypass in-kernel PM restrictions for non-kernel PMs") https://lore.kernel.org/all/20220516111435.72f35dca@canb.auug.org.au/ net/mptcp/subflow.c ae66fb2ba6c3 ("mptcp: Do TCP fallback on early DSS checksum failure") 0348c690ed37 ("mptcp: add the fallback check") f8d4bcacff3b ("mptcp: infinite mapping receiving") https://lore.kernel.org/all/20220519115837.380bb8d4@canb.auug.org.au/ Signed-off-by: Jakub Kicinski

mptcp: Do TCP fallback on early DSS checksum failure

2022-05-18T12:05:42Z

RFC 8684 section 3.7 describes several opportunities for a MPTCP connection to "fall back" to regular TCP early in the connection process, before it has been confirmed that MPTCP options can be successfully propagated on all SYN, SYN/ACK, and data packets. If a peer acknowledges the first received data packet with a regular TCP header (no MPTCP options), fallback is allowed. If the recipient of that first data packet finds a MPTCP DSS checksum error, this provides an opportunity to fail gracefully with a TCP fallback rather than resetting the connection (as might happen if a checksum failure were detected later). This commit modifies the checksum failure code to attempt fallback on the initial subflow of a MPTCP connection, only if it's a failure in the first data mapping. In cases where the peer initiates the connection, requests checksums, is the first to send data, and the peer is sending incorrect checksums (see https://github.com/multipath-tcp/mptcp_net-next/issues/275), this allows the connection to proceed as TCP rather than reset. Fixes: dd8bcd1768ff ("mptcp: validate the data checksum") Acked-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: David S. Miller

mptcp: fix checksum byte order

2022-05-18T12:05:42Z

The MPTCP code typecasts the checksum value to u16 and then converts it to big endian while storing the value into the MPTCP option. As a result, the wire encoding for little endian host is wrong, and that causes interoperabilty interoperability issues with other implementation or host with different endianness. Address the issue writing in the packet the unmodified __sum16 value. MPTCP checksum is disabled by default, interoperating with systems with bad mptcp-level csum encoding should cause fallback to TCP. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/275 Fixes: c5b39e26d003 ("mptcp: send out checksum for DSS") Fixes: 390b95a5fb84 ("mptcp: receive checksum for DSS") Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: David S. Miller

mptcp: fix subflow accounting on close

2022-05-14T00:04:30Z

If the PM closes a fully established MPJ subflow or the subflow creation errors out in it's early stage the subflows counter is not bumped accordingly. This change adds the missing accounting, additionally taking care of updating accordingly the 'accept_subflow' flag. Fixes: a88c9e496937 ("mptcp: do not block subflows creation on errors") Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: Jakub Kicinski

mptcp: read attributes of addr entries managed by userspace PMs

2022-05-04T09:49:31Z

This change introduces a parallel path in the kernel for retrieving the local id, flags, if_index for an addr entry in the context of an MPTCP connection that's being managed by a userspace PM. The userspace and in-kernel PM modes deviate in their procedures for obtaining this information. Acked-by: Paolo Abeni Signed-off-by: Kishen Maloor Signed-off-by: Mat Martineau Signed-off-by: David S. Miller

mptcp: store remote id from MP_JOIN SYN/ACK in local ctx

2022-05-03T23:54:54Z

This change reads the addr id assigned to the remote endpoint of a subflow from the MP_JOIN SYN/ACK message and stores it in the related subflow context. The remote id was not being captured prior to this change, and will now provide a consistent view of remote endpoints and their ids as seen through netlink events. Acked-by: Paolo Abeni Signed-off-by: Kishen Maloor Signed-off-by: Mat Martineau Signed-off-by: Jakub Kicinski

mptcp: bypass in-kernel PM restrictions for non-kernel PMs

2022-05-03T23:54:54Z

Current limits on the # of addresses/subflows must apply only to in-kernel PM managed sockets. Thus this change removes such restrictions on connections overseen by non-kernel (e.g. userspace) PMs. This change also ensures that the kernel does not record stats inside struct mptcp_pm_data updated along kernel code paths when exercised via non-kernel PMs. Additionally, address announcements are acknolwedged and subflow requests are honored only when it's deemed that a userspace path manager is active at the time. Acked-by: Paolo Abeni Signed-off-by: Kishen Maloor Signed-off-by: Mat Martineau Signed-off-by: Jakub Kicinski

mptcp: reset subflow when MP_FAIL doesn't respond

2022-04-27T09:45:54Z

This patch adds a new msk->flags bit MPTCP_FAIL_NO_RESPONSE, then reuses sk_timer to trigger a check if we have not received a response from the peer after sending MP_FAIL. If the peer doesn't respond properly, reset the subflow. Signed-off-by: Geliang Tang Signed-off-by: Mat Martineau Signed-off-by: David S. Miller