A CAN XL device is always capable to process CAN FD frames. The former
check when sending CAN FD frames relied on the existence of a CAN FD
device and did not check for a CAN XL device that would be correct too.
With this patch the CAN FD feature is enabled automatically when CAN XL
is switched on - and CAN FD cannot be switch off while CAN XL is enabled.
This precondition also leads to a clean up and reduction of checks in the
hot path in raw_rcv() and raw_sendmsg(). Some conditions are reordered to
handle simple checks first.
Fixes: 626332696d75 ("can: raw: add CAN XL support")
Signed-off-by: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
---
V2: fixed typo: devive -> device
V3: reorder checks in if statements to handle simple checks first
V4: use separate fd_frames variable instead of rolling back the value (mkl)
net/can/raw.c | 52 +++++++++++++++++++++++++++++++++------------------
1 file changed, 34 insertions(+), 18 deletions(-)
diff --git a/net/can/raw.c b/net/can/raw.c
index 81071cdb0301..f64469b98260 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -130,12 +130,12 @@ static void raw_rcv(struct sk_buff *oskb, void *data)
/* check the received tx sock reference */
if (!ro->recv_own_msgs && oskb->sk == sk)
return;
/* make sure to not pass oversized frames to the socket */
- if ((can_is_canfd_skb(oskb) && !ro->fd_frames && !ro->xl_frames) ||
- (can_is_canxl_skb(oskb) && !ro->xl_frames))
+ if ((!ro->fd_frames && can_is_canfd_skb(oskb)) ||
+ (!ro->xl_frames && can_is_canxl_skb(oskb)))
return;
/* eliminate multiple filter matches for the same skb */
if (this_cpu_ptr(ro->uniq)->skb == oskb &&
this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) {
@@ -521,10 +521,11 @@ static int raw_setsockopt(struct socket *sock, int level, int optname,
struct raw_sock *ro = raw_sk(sk);
struct can_filter *filter = NULL; /* dyn. alloc'ed filters */
struct can_filter sfilter; /* single filter */
struct net_device *dev = NULL;
can_err_mask_t err_mask = 0;
+ int fd_frames;
int count = 0;
int err = 0;
if (level != SOL_CAN_RAW)
return -EINVAL;
@@ -662,25 +663,33 @@ static int raw_setsockopt(struct socket *sock, int level, int optname,
return -EFAULT;
break;
case CAN_RAW_FD_FRAMES:
- if (optlen != sizeof(ro->fd_frames))
+ if (optlen != sizeof(fd_frames))
return -EINVAL;
- if (copy_from_sockptr(&ro->fd_frames, optval, optlen))
+ if (copy_from_sockptr(&fd_frames, optval, optlen))
return -EFAULT;
+ /* Enabling CAN XL includes CAN FD */
+ if (ro->xl_frames && !fd_frames)
+ return -EINVAL;
+
+ ro->fd_frames = fd_frames;
break;
case CAN_RAW_XL_FRAMES:
if (optlen != sizeof(ro->xl_frames))
return -EINVAL;
if (copy_from_sockptr(&ro->xl_frames, optval, optlen))
return -EFAULT;
+ /* Enabling CAN XL includes CAN FD */
+ if (ro->xl_frames)
+ ro->fd_frames = ro->xl_frames;
break;
case CAN_RAW_JOIN_FILTERS:
if (optlen != sizeof(ro->join_filters))
return -EINVAL;
@@ -784,10 +793,29 @@ static int raw_getsockopt(struct socket *sock, int level, int optname,
if (copy_to_user(optval, val, len))
return -EFAULT;
return 0;
}
+static bool raw_bad_txframe(struct raw_sock *ro, struct sk_buff *skb, int mtu)
+{
+ /* Classical CAN -> no checks for flags and device capabilities */
+ if (can_is_can_skb(skb))
+ return false;
+
+ /* CAN FD -> needs to be enabled and a CAN FD or CAN XL device */
+ if (ro->fd_frames && can_is_canfd_skb(skb) &&
+ (mtu == CANFD_MTU || can_is_canxl_dev_mtu(mtu)))
+ return false;
+
+ /* CAN XL -> needs to be enabled and a CAN XL device */
+ if (ro->xl_frames && can_is_canxl_skb(skb) &&
+ can_is_canxl_dev_mtu(mtu))
+ return false;
+
+ return true;
+}
+
static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
{
struct sock *sk = sock->sk;
struct raw_sock *ro = raw_sk(sk);
struct sockcm_cookie sockc;
@@ -831,24 +859,12 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
err = memcpy_from_msg(skb_put(skb, size), msg, size);
if (err < 0)
goto free_skb;
err = -EINVAL;
- if (ro->xl_frames && can_is_canxl_dev_mtu(dev->mtu)) {
- /* CAN XL, CAN FD and Classical CAN */
- if (!can_is_canxl_skb(skb) && !can_is_canfd_skb(skb) &&
- !can_is_can_skb(skb))
- goto free_skb;
- } else if (ro->fd_frames && dev->mtu == CANFD_MTU) {
- /* CAN FD and Classical CAN */
- if (!can_is_canfd_skb(skb) && !can_is_can_skb(skb))
- goto free_skb;
- } else {
- /* Classical CAN */
- if (!can_is_can_skb(skb))
- goto free_skb;
- }
+ if (raw_bad_txframe(ro, skb, dev->mtu))
+ goto free_skb;
sockcm_init(&sockc, sk);
if (msg->msg_controllen) {
err = sock_cmsg_send(sk, msg, &sockc);
if (unlikely(err))
--
2.39.0
