On 2016/6/30 22:13, Eric Dumazet wrote:
> From: Eric Dumazet <eduma...@google.com>
>
> 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 <eduma...@google.com>
> Reported-by: Dmitry Vyukov <dvyu...@google.com>
> ---
> 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..8ad491ab1d01 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 {
>
>
>
> .
It is fine to me.
Acked-by: Ding Tianhong <dingtianh...@huawei.com>
>
