wg-quick: linux: only touch net.ipv4 for v4

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

diff --git a/src/wg-quick/linux.bash b/src/wg-quick/linux.bash
index e690944d39c62fdff07daebab28f8e70b955775a..cf72d41ef89a74919d54ecd6582fbd23739a119c 100755 (executable)
--- a/src/wg-quick/linux.bash
+++ b/src/wg-quick/linux.bash
@@ -194,9 +194,11 @@ add_default() {
        cmd ip $proto route add "$1" dev "$INTERFACE" table $table
        cmd ip $proto rule add not fwmark $table table $table
        cmd ip $proto rule add table main suppress_prefixlength 0
-       while read -r key _ value; do
-               [[ $value -eq 1 ]] && sysctl -q "$key=2"
-       done < <(sysctl -a -r '^net\.ipv4.conf\.[^ .=]+\.rp_filter$')
+       if [[ $proto == -4 ]]; then
+               while read -r key _ value; do
+                       [[ $value -eq 1 ]] && sysctl -q "$key=2"
+               done < <(sysctl -a -r '^net\.ipv4.conf\.[^ .=]+\.rp_filter$')
+       fi
        return 0
 }