In d9ee51e, virNetDevIPCheckIPv6Forwarding was updated to walk the contents of /proc/net/ipv6_route so that it could check to see if the RTF_ADDRCONF was set on any IPv6 routes to ultimately determine if enabling forwarding would result in an error due to accept_ra=1 being set on the interface. The implementation added in that commit limited the number of routes that could be read from /proc/net/ipv6_route to 100_000, each with 150 characters. This is problematic for machines that have a full IPv6 routing table, as the IPv6 routing table has now grown to over 160_000 (it was closer to 100_000 at the time of that commit). This patch increases the maximum route size from 100_000 to 1_000_000. While a million routes is somewhat arbitrary, it's meant to be a value that can be supported for the forseeable future. APNIC, one of the five regional internet registries, recently published a forecast of IPv6 table growth which anticipates a worst-case growth to 1_000_000 in January of 2029. Signed-off-by: Brooks Swinnerton <bswinnerton(a)gmail.com&gt; --- src/util/virnetdevip.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/util/virnetdevip.c b/src/util/virnetdevip.c index 2eacb64ebe..034b392ee7 100644 --- a/src/util/virnetdevip.c +++ b/src/util/virnetdevip.c @@ -529,7 +529,7 @@ virNetDevIPCheckIPv6Forwarding(void) char *cur; g_autofree char *buf = NULL; /* lines are 150 chars */ - enum {MAX_ROUTE_SIZE = 150*100000}; + enum {MAX_ROUTE_SIZE = 150*1000000}; /* This is /proc/sys/net/ipv6/conf/all/accept_ra */ int all_accept_ra = virNetDevIPGetAcceptRA(NULL); -- 2.39.1