[source] base-files: fix wan6 interface config generation for pppoe

[LEDE Commits]

dedeckeh pushed a commit to source.git, branch master:
https://git.lede-project.org/400c5f03c30b39ef149a1edc0a4b5b2c0bb94317

commit 400c5f03c30b39ef149a1edc0a4b5b2c0bb94317
Author: Hans Dedecker <dedeckeh at gmail.com>
AuthorDate: Mon Sep 18 09:18:36 2017 +0200

    base-files: fix wan6 interface config generation for pppoe
    
    Setting ipv6 to auto in case of a pppoe interface will trigger the
    creation of a dynamic wan_6 interface meaning two IPv6 interfaces
    (wan6 and wan_6) will be active on top of the pppoe interface.
    This leads to unpredictable behavior in the network; therefore set
    ipv6 to 1 which will prevent the dynamic creation of the wan_6
    interface.
    Further alias the wan6 interface on top of the wan interface for pppoe
    as the wan6 interface can only be started when the link local address is
    ready. In case of pppoe the link local address is negotiated during the
    Internet Protocol Control Protocol when the PPP link is setup meaning
    all the IP address info is only available when the wan interface is up.
    
    Signed-off-by: Hans Dedecker <dedeckeh at gmail.com>
---
 package/base-files/Makefile                  | 2 +-
 package/base-files/files/bin/config_generate | 7 ++-----
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/package/base-files/Makefile b/package/base-files/Makefile
index d8ee46e..0c0c1ce 100644
--- a/package/base-files/Makefile
+++ b/package/base-files/Makefile
@@ -11,7 +11,7 @@ include $(INCLUDE_DIR)/kernel.mk
 include $(INCLUDE_DIR)/version.mk
 
 PKG_NAME:=base-files
-PKG_RELEASE:=175
+PKG_RELEASE:=176
 PKG_FLAGS:=nonshared
 
 PKG_FILE_DEPENDS:=$(PLATFORM_DIR)/ $(GENERIC_PLATFORM_DIR)/base-files/
diff --git a/package/base-files/files/bin/config_generate b/package/base-files/files/bin/config_generate
index 6230b08..a8311fc 100755
--- a/package/base-files/files/bin/config_generate
+++ b/package/base-files/files/bin/config_generate
@@ -119,17 +119,14 @@ generate_network() {
 		;;
 
 		pppoe)
-			# fixup IPv6 slave interface
-			ifname="pppoe-$1"
-
 			uci -q batch <<-EOF
 				set network.$1.proto='pppoe'
 				set network.$1.username='username'
 				set network.$1.password='password'
-				set network.$1.ipv6='auto'
+				set network.$1.ipv6='1'
 				delete network.${1}6
 				set network.${1}6='interface'
-				set network.${1}6.ifname='$ifname'
+				set network.${1}6.ifname='@${1}'
 				set network.${1}6.proto='dhcpv6'
 			EOF
 		;;