From: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> commit 332b05ca7a438f857c61a3c21a88489a21532364 upstream. This patch adds a check to limit the number of can_filters that can be set via setsockopt on CAN_RAW sockets. Otherwise allocations > MAX_ORDER are not prevented resulting in a warning. Reference: https://lkml.org/lkml/2016/12/2/230 Reported-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Tested-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> Signed-off-by: Willy Tarreau <w@xxxxxx> --- include/uapi/linux/can.h | 1 + net/can/raw.c | 3 +++ 2 files changed, 4 insertions(+) diff --git a/include/uapi/linux/can.h b/include/uapi/linux/can.h index e52958d..3018528 100644 --- a/include/uapi/linux/can.h +++ b/include/uapi/linux/can.h @@ -158,5 +158,6 @@ struct can_filter { }; #define CAN_INV_FILTER 0x20000000U /* to be set in can_filter.can_id */ +#define CAN_RAW_FILTER_MAX 512 /* maximum number of can_filter set via setsockopt() */ #endif /* CAN_H */ diff --git a/net/can/raw.c b/net/can/raw.c index f4d8648..602be0e 100644 --- a/net/can/raw.c +++ b/net/can/raw.c @@ -470,6 +470,9 @@ static int raw_setsockopt(struct socket *sock, int level, int optname, if (optlen % sizeof(struct can_filter) != 0) return -EINVAL; + if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter)) + return -EINVAL; + count = optlen / sizeof(struct can_filter); if (count > 1) { -- 2.8.0.rc2.1.gbe9624a