| Message ID | 89e5acb6c86bb10675697dabbefafad7088dc0f6.1611590423.git.pabeni@redhat.com (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Stephen Hemminger |
| Headers | show |
| Series | [iproute2] ss: do not emit warn while dumping MPTCP on old kernels | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On Mon, 2021-01-25 at 17:02 +0100, Paolo Abeni wrote: > Prior to this commit, running 'ss' on a kernel older than v5.9 > bumps an error message: > > RTNETLINK answers: Invalid argument Thanks, works perfectly for me. -Tommi > When asked to dump protocol number > 255 - that is: MPTCP - 'ss' > adds an INET_DIAG_REQ_PROTOCOL attribute, unsupported by the older > kernel. > > Avoid the warning ignoring filter issues when INET_DIAG_REQ_PROTOCOL > is used. > > Additionally older kernel end-up invoking tcpdiag_send(), which > in turn will try to dump DCCP socks. Bail early in such function, > as the kernel does not implement an MPTCPDIAG_GET request. > > Reported-by: "Rantala, Tommi T. (Nokia - FI/Espoo)" < > tommi.t.rantala@nokia.com> > Fixes: 9c3be2c0eee0 ("ss: mptcp: add msk diag interface support") > Signed-off-by: Paolo Abeni <pabeni@redhat.com> > --- > misc/ss.c | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/misc/ss.c b/misc/ss.c > index 0593627b..ad46f9db 100644 > --- a/misc/ss.c > +++ b/misc/ss.c > @@ -3404,7 +3404,7 @@ static int tcpdiag_send(int fd, int protocol, struct > filter *f) > struct iovec iov[3]; > int iovlen = 1; > > - if (protocol == IPPROTO_UDP) > + if (protocol == IPPROTO_UDP || protocol == IPPROTO_MPTCP) > return -1; > > if (protocol == IPPROTO_TCP) > @@ -3623,6 +3623,14 @@ static int inet_show_netlink(struct filter *f, FILE > *dump_fp, int protocol) > if (preferred_family == PF_INET6) > family = PF_INET6; > > + /* extended protocol will use INET_DIAG_REQ_PROTOCOL, > + * not supported by older kernels. On such kernel > + * rtnl_dump will bail with rtnl_dump_error(). > + * Suppress the error to avoid confusing the user > + */ > + if (protocol > 255) > + rth.flags |= RTNL_HANDLE_F_SUPPRESS_NLERR; > + > again: > if ((err = sockdiag_send(family, rth.fd, protocol, f))) > goto Exit;
diff --git a/misc/ss.c b/misc/ss.c index 0593627b..ad46f9db 100644 --- a/misc/ss.c +++ b/misc/ss.c @@ -3404,7 +3404,7 @@ static int tcpdiag_send(int fd, int protocol, struct filter *f) struct iovec iov[3]; int iovlen = 1; - if (protocol == IPPROTO_UDP) + if (protocol == IPPROTO_UDP || protocol == IPPROTO_MPTCP) return -1; if (protocol == IPPROTO_TCP) @@ -3623,6 +3623,14 @@ static int inet_show_netlink(struct filter *f, FILE *dump_fp, int protocol) if (preferred_family == PF_INET6) family = PF_INET6; + /* extended protocol will use INET_DIAG_REQ_PROTOCOL, + * not supported by older kernels. On such kernel + * rtnl_dump will bail with rtnl_dump_error(). + * Suppress the error to avoid confusing the user + */ + if (protocol > 255) + rth.flags |= RTNL_HANDLE_F_SUPPRESS_NLERR; + again: if ((err = sockdiag_send(family, rth.fd, protocol, f))) goto Exit;
Prior to this commit, running 'ss' on a kernel older than v5.9 bumps an error message: RTNETLINK answers: Invalid argument When asked to dump protocol number > 255 - that is: MPTCP - 'ss' adds an INET_DIAG_REQ_PROTOCOL attribute, unsupported by the older kernel. Avoid the warning ignoring filter issues when INET_DIAG_REQ_PROTOCOL is used. Additionally older kernel end-up invoking tcpdiag_send(), which in turn will try to dump DCCP socks. Bail early in such function, as the kernel does not implement an MPTCPDIAG_GET request. Reported-by: "Rantala, Tommi T. (Nokia - FI/Espoo)" <tommi.t.rantala@nokia.com> Fixes: 9c3be2c0eee0 ("ss: mptcp: add msk diag interface support") Signed-off-by: Paolo Abeni <pabeni@redhat.com> --- misc/ss.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)