From 557d5e9fecff500b010a9be44dda1ae000f45039 Mon Sep 17 00:00:00 2001 From: Matthias Greiner Date: Mon, 22 May 2017 03:11:25 +0200 Subject: [PATCH] Allow bad MTU values with warning to be able to connect to the machine. (#5954) Ensure the MTU value is valid. Emit a warning and ignore otherwise. (cherry picked from commit 955d99edc7991386a36e3d33924cc584931fde91) --- src/libsystemd-network/sd-dhcp-lease.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/src/libsystemd-network/sd-dhcp-lease.c b/src/libsystemd-network/sd-dhcp-lease.c index 7fed55c5fc..565ec4cbe4 100644 --- a/src/libsystemd-network/sd-dhcp-lease.c +++ b/src/libsystemd-network/sd-dhcp-lease.c @@ -594,6 +594,11 @@ int dhcp_lease_parse_options(uint8_t code, uint8_t len, const void *option, void r = lease_parse_u16(option, len, &lease->mtu, 68); if (r < 0) log_debug_errno(r, "Failed to parse MTU, ignoring: %m"); + if (lease->mtu < DHCP_DEFAULT_MIN_SIZE) { + log_warning("MTU value of %d too small. Using default MTU value of %d instead.", lease->mtu, DHCP_DEFAULT_MIN_SIZE); + lease->mtu = DHCP_DEFAULT_MIN_SIZE; + } + break; case SD_DHCP_OPTION_DOMAIN_NAME: