net: sctp: only warn in proc_sctp_do_alpha_beta if write

Only warn if the value is written to alpha or beta. We don't care
emitting a one-time warning when only reading it.

Reported-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Reviewed-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c
index 12c7e01..2e9ada1 100644 (file)
--- a/net/sctp/sysctl.c
+++ b/net/sctp/sysctl.c
@@ -424,8 +424,9 @@ static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
                                   void __user *buffer, size_t *lenp,
                                   loff_t *ppos)
 {
-       pr_warn_once("Changing rto_alpha or rto_beta may lead to "
-                    "suboptimal rtt/srtt estimations!\n");
+       if (write)
+               pr_warn_once("Changing rto_alpha or rto_beta may lead to "
+                            "suboptimal rtt/srtt estimations!\n");
 
        return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
 }