From f87fda00b6ed232a817c655b8d179b48bde8fdbe Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 30 Jun 2016 16:13:41 +0200 Subject: [PATCH] bonding: prevent out of bound accesses ether_addr_equal_64bits() requires some care about its arguments, namely that 8 bytes might be read, even if last 2 byte values are not used. KASan detected a violation with null_mac_addr and lacpdu_mcast_addr in bond_3ad.c Same problem with mac_bcast[] and mac_v6_allmcast[] in bond_alb.c : Although the 8-byte alignment was there, KASan would detect out of bound accesses. Fixes: 815117adaf5b ("bonding: use ether_addr_equal_unaligned for bond addr compare") Fixes: bb54e58929f3 ("bonding: Verify RX LACPDU has proper dest mac-addr") Fixes: 885a136c52a8 ("bonding: use compare_ether_addr_64bits() in ALB") Signed-off-by: Eric Dumazet Reported-by: Dmitry Vyukov Acked-by: Dmitry Vyukov Acked-by: Nikolay Aleksandrov Acked-by: Ding Tianhong Signed-off-by: David S. Miller --- drivers/net/bonding/bond_3ad.c | 11 +++++++---- drivers/net/bonding/bond_alb.c | 7 ++----- include/net/bonding.h | 7 ++++++- 3 files changed, 15 insertions(+), 10 deletions(-) diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c index ca81f46ea1aa..edc70ffad660 100644 --- a/drivers/net/bonding/bond_3ad.c +++ b/drivers/net/bonding/bond_3ad.c @@ -101,11 +101,14 @@ enum ad_link_speed_type { #define MAC_ADDRESS_EQUAL(A, B) \ ether_addr_equal_64bits((const u8 *)A, (const u8 *)B) -static struct mac_addr null_mac_addr = { { 0, 0, 0, 0, 0, 0 } }; +static const u8 null_mac_addr[ETH_ALEN + 2] __long_aligned = { + 0, 0, 0, 0, 0, 0 +}; static u16 ad_ticks_per_sec; static const int ad_delta_in_ticks = (AD_TIMER_INTERVAL * HZ) / 1000; -static const u8 lacpdu_mcast_addr[ETH_ALEN] = MULTICAST_LACPDU_ADDR; +static const u8 lacpdu_mcast_addr[ETH_ALEN + 2] __long_aligned = + MULTICAST_LACPDU_ADDR; /* ================= main 802.3ad protocol functions ================== */ static int ad_lacpdu_send(struct port *port); @@ -1739,7 +1742,7 @@ static void ad_clear_agg(struct aggregator *aggregator) aggregator->is_individual = false; aggregator->actor_admin_aggregator_key = 0; aggregator->actor_oper_aggregator_key = 0; - aggregator->partner_system = null_mac_addr; + eth_zero_addr(aggregator->partner_system.mac_addr_value); aggregator->partner_system_priority = 0; aggregator->partner_oper_aggregator_key = 0; aggregator->receive_state = 0; @@ -1761,7 +1764,7 @@ static void ad_initialize_agg(struct aggregator *aggregator) if (aggregator) { ad_clear_agg(aggregator); - aggregator->aggregator_mac_address = null_mac_addr; + eth_zero_addr(aggregator->aggregator_mac_address.mac_addr_value); aggregator->aggregator_identifier = 0; aggregator->slave = NULL; } diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c index c5ac160a8ae9..551f0f8dead3 100644 --- a/drivers/net/bonding/bond_alb.c +++ b/drivers/net/bonding/bond_alb.c @@ -42,13 +42,10 @@ -#ifndef __long_aligned -#define __long_aligned __attribute__((aligned((sizeof(long))))) -#endif -static const u8 mac_bcast[ETH_ALEN] __long_aligned = { +static const u8 mac_bcast[ETH_ALEN + 2] __long_aligned = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; -static const u8 mac_v6_allmcast[ETH_ALEN] __long_aligned = { +static const u8 mac_v6_allmcast[ETH_ALEN + 2] __long_aligned = { 0x33, 0x33, 0x00, 0x00, 0x00, 0x01 }; static const int alb_delta_in_ticks = HZ / ALB_TIMER_TICKS_PER_SEC; diff --git a/include/net/bonding.h b/include/net/bonding.h index 791800ddd6d9..6360c259da6d 100644 --- a/include/net/bonding.h +++ b/include/net/bonding.h @@ -34,6 +34,9 @@ #define BOND_DEFAULT_MIIMON 100 +#ifndef __long_aligned +#define __long_aligned __attribute__((aligned((sizeof(long))))) +#endif /* * Less bad way to call ioctl from within the kernel; this needs to be * done some other way to get the call out of interrupt context. @@ -138,7 +141,9 @@ struct bond_params { struct reciprocal_value reciprocal_packets_per_slave; u16 ad_actor_sys_prio; u16 ad_user_port_key; - u8 ad_actor_system[ETH_ALEN]; + + /* 2 bytes of padding : see ether_addr_equal_64bits() */ + u8 ad_actor_system[ETH_ALEN + 2]; }; struct bond_parm_tbl {