diff options
| -rw-r--r-- | drivers/net/can/dev.c | 35 | ||||
| -rw-r--r-- | include/linux/can/dev.h | 33 |
2 files changed, 59 insertions, 9 deletions
diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c index f03d7a481a8..239e4dd92ca 100644 --- a/drivers/net/can/dev.c +++ b/drivers/net/can/dev.c @@ -33,6 +33,39 @@ MODULE_DESCRIPTION(MOD_DESC); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); +/* CAN DLC to real data length conversion helpers */ + +static const u8 dlc2len[] = {0, 1, 2, 3, 4, 5, 6, 7, + 8, 12, 16, 20, 24, 32, 48, 64}; + +/* get data length from can_dlc with sanitized can_dlc */ +u8 can_dlc2len(u8 can_dlc) +{ + return dlc2len[can_dlc & 0x0F]; +} +EXPORT_SYMBOL_GPL(can_dlc2len); + +static const u8 len2dlc[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, /* 0 - 8 */ + 9, 9, 9, 9, /* 9 - 12 */ + 10, 10, 10, 10, /* 13 - 16 */ + 11, 11, 11, 11, /* 17 - 20 */ + 12, 12, 12, 12, /* 21 - 24 */ + 13, 13, 13, 13, 13, 13, 13, 13, /* 25 - 32 */ + 14, 14, 14, 14, 14, 14, 14, 14, /* 33 - 40 */ + 14, 14, 14, 14, 14, 14, 14, 14, /* 41 - 48 */ + 15, 15, 15, 15, 15, 15, 15, 15, /* 49 - 56 */ + 15, 15, 15, 15, 15, 15, 15, 15}; /* 57 - 64 */ + +/* map the sanitized data length to an appropriate data length code */ +u8 can_len2dlc(u8 len) +{ + if (unlikely(len > 64)) + return 0xF; + + return len2dlc[len]; +} +EXPORT_SYMBOL_GPL(can_len2dlc); + #ifdef CONFIG_CAN_CALC_BITTIMING #define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */ @@ -454,7 +487,7 @@ EXPORT_SYMBOL_GPL(can_bus_off); static void can_setup(struct net_device *dev) { dev->type = ARPHRD_CAN; - dev->mtu = sizeof(struct can_frame); + dev->mtu = CAN_MTU; dev->hard_header_len = 0; dev->addr_len = 0; dev->tx_queue_len = 10; diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h index 5d2efe7e3f1..ee5a771fb20 100644 --- a/include/linux/can/dev.h +++ b/include/linux/can/dev.h @@ -61,23 +61,40 @@ struct can_priv { * To be used in the CAN netdriver receive path to ensure conformance with * ISO 11898-1 Chapter 8.4.2.3 (DLC field) */ -#define get_can_dlc(i) (min_t(__u8, (i), 8)) +#define get_can_dlc(i) (min_t(__u8, (i), CAN_MAX_DLC)) +#define get_canfd_dlc(i) (min_t(__u8, (i), CANFD_MAX_DLC)) /* Drop a given socketbuffer if it does not contain a valid CAN frame. */ static inline int can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb) { - const struct can_frame *cf = (struct can_frame *)skb->data; - - if (unlikely(skb->len != sizeof(*cf) || cf->can_dlc > 8)) { - kfree_skb(skb); - dev->stats.tx_dropped++; - return 1; - } + const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; + + if (skb->protocol == htons(ETH_P_CAN)) { + if (unlikely(skb->len != CAN_MTU || + cfd->len > CAN_MAX_DLEN)) + goto inval_skb; + } else if (skb->protocol == htons(ETH_P_CANFD)) { + if (unlikely(skb->len != CANFD_MTU || + cfd->len > CANFD_MAX_DLEN)) + goto inval_skb; + } else + goto inval_skb; return 0; + +inval_skb: + kfree_skb(skb); + dev->stats.tx_dropped++; + return 1; } +/* get data length from can_dlc with sanitized can_dlc */ +u8 can_dlc2len(u8 can_dlc); + +/* map the sanitized data length to an appropriate data length code */ +u8 can_len2dlc(u8 len); + struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max); void free_candev(struct net_device *dev); |