From: Mat Martineau Date: Mon, 25 Jul 2022 20:52:31 +0000 (-0700) Subject: mptcp: Do not return EINPROGRESS when subflow creation succeeds X-Git-Tag: v5.19~17^2~10 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=b5177ed92bf6f9d90a2493ed51c1327e088be1df;p=users%2Fdwmw2%2Flinux.git mptcp: Do not return EINPROGRESS when subflow creation succeeds New subflows are created within the kernel using O_NONBLOCK, so EINPROGRESS is the expected return value from kernel_connect(). __mptcp_subflow_connect() has the correct logic to consider EINPROGRESS to be a successful case, but it has also used that error code as its return value. Before v5.19 this was benign: all the callers ignored the return value. Starting in v5.19 there is a MPTCP_PM_CMD_SUBFLOW_CREATE generic netlink command that does use the return value, so the EINPROGRESS gets propagated to userspace. Make __mptcp_subflow_connect() always return 0 on success instead. Fixes: ec3edaa7ca6c ("mptcp: Add handling of outgoing MP_JOIN requests") Fixes: 702c2f646d42 ("mptcp: netlink: allow userspace-driven subflow establishment") Acked-by: Paolo Abeni Signed-off-by: Mat Martineau Link: https://lore.kernel.org/r/20220725205231.87529-1-mathew.j.martineau@linux.intel.com Signed-off-by: Jakub Kicinski --- diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 63e8892ec807d..af28f3b603899 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -1533,7 +1533,7 @@ int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, mptcp_sock_graft(ssk, sk->sk_socket); iput(SOCK_INODE(sf)); WRITE_ONCE(msk->allow_infinite_fallback, false); - return err; + return 0; failed_unlink: list_del(&subflow->node);