ppp: backport patches improving ppp interface creation

[openwrt/staging/stintel.git] / package / network / services / ppp / patches / 140-pppd-Fix-compilation-with-older-glibc-or-kernel-head.patch

diff --git a/package/network/services/ppp/patches/140-pppd-Fix-compilation-with-older-glibc-or-kernel-head.patch b/package/network/services/ppp/patches/140-pppd-Fix-compilation-with-older-glibc-or-kernel-head.patch
new file mode 100644 (file)
index 0000000..154ac72
--- /dev/null
+++ b/package/network/services/ppp/patches/140-pppd-Fix-compilation-with-older-glibc-or-kernel-head.patch
@@ -0,0 +1,54 @@
+From 98ec18f098e5ef68e3a8cc6954fcaf5a7fb8b7be Mon Sep 17 00:00:00 2001
+From: pali <7141871+pali@users.noreply.github.com>
+Date: Mon, 15 Feb 2021 07:54:01 +0100
+Subject: [PATCH] pppd: Fix compilation with older glibc or kernel headers
+ (#248)
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+glibc versions prior to 2.24 do not define SOL_NETLINK and linux kernel
+versions prior to 4.3 do not define NETLINK_CAP_ACK. So add fallback
+definitions for these macros into pppd/sys-linux.c file.
+
+Also extend description why we call SOL_NETLINK/NETLINK_CAP_ACK option.
+
+Signed-off-by: Pali Rohár <pali@kernel.org>
+---
+ pppd/sys-linux.c | 18 +++++++++++++++++-
+ 1 file changed, 17 insertions(+), 1 deletion(-)
+
+--- a/pppd/sys-linux.c
++++ b/pppd/sys-linux.c
+@@ -125,6 +125,14 @@
+ #include <linux/netlink.h>
+ #include <linux/rtnetlink.h>
+ #include <linux/if_addr.h>
++/* glibc versions prior to 2.24 do not define SOL_NETLINK */
++#ifndef SOL_NETLINK
++#define SOL_NETLINK 270
++#endif
++/* linux kernel versions prior to 4.3 do not define/support NETLINK_CAP_ACK */
++#ifndef NETLINK_CAP_ACK
++#define NETLINK_CAP_ACK 10
++#endif
+ #endif
+ 
+ #include "pppd.h"
+@@ -2843,7 +2851,15 @@ static int append_peer_ipv6_address(unsi
+     if (fd < 0)
+         return 0;
+ 
+-    /* do not ask for error message content */
++    /*
++     * Tell kernel to not send to us payload of acknowledgment error message.
++     * NETLINK_CAP_ACK option is supported since Linux kernel version 4.3 and
++     * older kernel versions always send full payload in acknowledgment netlink
++     * message. We ignore payload of this message as we need only error code,
++     * to check if our set remote peer address request succeeded or failed.
++     * So ignore return value from the following setsockopt() call as setting
++     * option NETLINK_CAP_ACK means for us just a kernel hint / optimization.
++     */
+     one = 1;
+     setsockopt(fd, SOL_NETLINK, NETLINK_CAP_ACK, &one, sizeof(one));
+