When UEFI receives IPMP echo packets it will enter Ip4IcmpReplyEcho function, and then call Ip4Output. However, if Ip4Output gets some error and exits early, e.g. fails to find the route entry, memory buffer of "Data" gets no chance to be freed and memory leak will be caused. If there is such an attacker in the network, we will see UEFI runs out of memory and system hangs.

So we explicitly free the memory when error status is returned.

Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Junbiao Hong hongjunbiao@huawei.com Signed-off-by: Heyi Guo heyi.guo@linaro.org Reviewed-by: Siyuan Fu siyuan.fu@intel.com Reviewed-by: Jiaxin Wu jiaxin.wu@intel.com Cc: Star Zeng star.zeng@intel.com Cc: Eric Dong eric.dong@intel.com Cc: Ruiyu Ni ruiyu.ni@intel.com Cc: Siyuan Fu siyuan.fu@intel.com Cc: Jiaxin Wu jiaxin.wu@intel.com --- MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Icmp.c | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Icmp.c b/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Icmp.c index b4b0864..ed6bdbe 100644 --- a/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Icmp.c +++ b/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Icmp.c @@ -267,6 +267,9 @@ Ip4IcmpReplyEcho ( Ip4SysPacketSent, NULL ); + if (EFI_ERROR (Status)) { + NetbufFree (Data); + }

ON_EXIT: NetbufFree (Packet);