ss: Fix for added diag support check

Commit 9f66764e30 ("libnetlink: Add test for error code returned from
netlink reply") changed rtnl_dump_filter_l() to return an error in case
NLMSG_DONE would contain one, even if it was ENOENT.

This in turn breaks ss when it tries to dump DCCP sockets on a system
without support for it: The function tcp_show(), which is shared between
TCP and DCCP, will start parsing /proc since inet_show_netlink() returns
an error - yet it parses /proc/net/tcp which doesn't make sense for DCCP
sockets at all.

On my system, a call to 'ss' without further arguments prints the list
of connected TCP sockets twice.

Fix this by introducing a dedicated function dccp_show() which does not
have a fallback to /proc, just like sctp_show(). And since tcp_show()
is no longer "multi-purpose", drop it's socktype parameter.

Fixes: 9f66764e30 ("libnetlink: Add test for error code returned from netlink reply")
Signed-off-by: Phil Sutter <phil@nwl.cc>
This commit is contained in:
Phil Sutter 2017-08-28 19:31:22 +02:00 committed by Stephen Hemminger
parent c4fc474b88
commit 6c6bbc30f4
1 changed files with 16 additions and 4 deletions

View File

@ -2753,7 +2753,7 @@ static int tcp_show_netlink_file(struct filter *f)
return err;
}
static int tcp_show(struct filter *f, int socktype)
static int tcp_show(struct filter *f)
{
FILE *fp = NULL;
char *buf = NULL;
@ -2768,7 +2768,7 @@ static int tcp_show(struct filter *f, int socktype)
return tcp_show_netlink_file(f);
if (!getenv("PROC_NET_TCP") && !getenv("PROC_ROOT")
&& inet_show_netlink(f, NULL, socktype) == 0)
&& inet_show_netlink(f, NULL, IPPROTO_TCP) == 0)
return 0;
/* Sigh... We have to parse /proc/net/tcp... */
@ -2836,6 +2836,18 @@ outerr:
} while (0);
}
static int dccp_show(struct filter *f)
{
if (!filter_af_get(f, AF_INET) && !filter_af_get(f, AF_INET6))
return 0;
if (!getenv("PROC_NET_DCCP") && !getenv("PROC_ROOT")
&& inet_show_netlink(f, NULL, IPPROTO_DCCP) == 0)
return 0;
return 0;
}
static int sctp_show(struct filter *f)
{
if (!filter_af_get(f, AF_INET) && !filter_af_get(f, AF_INET6))
@ -4390,9 +4402,9 @@ int main(int argc, char *argv[])
if (current_filter.dbs & (1<<UDP_DB))
udp_show(&current_filter);
if (current_filter.dbs & (1<<TCP_DB))
tcp_show(&current_filter, IPPROTO_TCP);
tcp_show(&current_filter);
if (current_filter.dbs & (1<<DCCP_DB))
tcp_show(&current_filter, IPPROTO_DCCP);
dccp_show(&current_filter);
if (current_filter.dbs & (1<<SCTP_DB))
sctp_show(&current_filter);