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can: skb:: move can_dropped_invalid_skb and can_skb_headroom_valid to…
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… skb.c

The functions can_dropped_invalid_skb() and can_skb_headroom_valid()
grew a lot over the years to a point which it does make much sense to
have them defined as static inline in header files. Move those two
functions to the .c counterpart of skb.h.

can_skb_headroom_valid() only caller being can_dropped_invalid_skb(),
the declaration is removed from the header. Only
can_dropped_invalid_skb() gets its symbol exported.

While doing so, do a small cleanup: add brackets around the else block
in can_dropped_invalid_skb().

Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
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vincent-mailhol authored and intel-lab-lkp committed May 13, 2022
1 parent fc15944 commit 8f56e6b
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Showing 2 changed files with 59 additions and 58 deletions.
58 changes: 58 additions & 0 deletions drivers/net/can/dev/skb.c
Expand Up @@ -252,3 +252,61 @@ struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf)
return skb;
}
EXPORT_SYMBOL_GPL(alloc_can_err_skb);

/* Check for outgoing skbs that have not been created by the CAN subsystem */
static bool can_skb_headroom_valid(struct net_device *dev, struct sk_buff *skb)
{
/* af_packet creates a headroom of HH_DATA_MOD bytes which is fine */
if (WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct can_skb_priv)))
return false;

/* af_packet does not apply CAN skb specific settings */
if (skb->ip_summed == CHECKSUM_NONE) {
/* init headroom */
can_skb_prv(skb)->ifindex = dev->ifindex;
can_skb_prv(skb)->skbcnt = 0;

skb->ip_summed = CHECKSUM_UNNECESSARY;

/* perform proper loopback on capable devices */
if (dev->flags & IFF_ECHO)
skb->pkt_type = PACKET_LOOPBACK;
else
skb->pkt_type = PACKET_HOST;

skb_reset_mac_header(skb);
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
}

return true;
}

/* Drop a given socketbuffer if it does not contain a valid CAN frame. */
bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb)
{
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;
}

if (!can_skb_headroom_valid(dev, skb))
goto inval_skb;

return false;

inval_skb:
kfree_skb(skb);
dev->stats.tx_dropped++;
return true;
}
EXPORT_SYMBOL_GPL(can_dropped_invalid_skb);
59 changes: 1 addition & 58 deletions include/linux/can/skb.h
Expand Up @@ -31,6 +31,7 @@ struct sk_buff *alloc_canfd_skb(struct net_device *dev,
struct canfd_frame **cfd);
struct sk_buff *alloc_can_err_skb(struct net_device *dev,
struct can_frame **cf);
bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb);

/*
* The struct can_skb_priv is used to transport additional information along
Expand Down Expand Up @@ -96,64 +97,6 @@ static inline struct sk_buff *can_create_echo_skb(struct sk_buff *skb)
return nskb;
}

/* Check for outgoing skbs that have not been created by the CAN subsystem */
static inline bool can_skb_headroom_valid(struct net_device *dev,
struct sk_buff *skb)
{
/* af_packet creates a headroom of HH_DATA_MOD bytes which is fine */
if (WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct can_skb_priv)))
return false;

/* af_packet does not apply CAN skb specific settings */
if (skb->ip_summed == CHECKSUM_NONE) {
/* init headroom */
can_skb_prv(skb)->ifindex = dev->ifindex;
can_skb_prv(skb)->skbcnt = 0;

skb->ip_summed = CHECKSUM_UNNECESSARY;

/* perform proper loopback on capable devices */
if (dev->flags & IFF_ECHO)
skb->pkt_type = PACKET_LOOPBACK;
else
skb->pkt_type = PACKET_HOST;

skb_reset_mac_header(skb);
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
}

return true;
}

/* Drop a given socketbuffer if it does not contain a valid CAN frame. */
static inline bool can_dropped_invalid_skb(struct net_device *dev,
struct sk_buff *skb)
{
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;

if (!can_skb_headroom_valid(dev, skb))
goto inval_skb;

return false;

inval_skb:
kfree_skb(skb);
dev->stats.tx_dropped++;
return true;
}

static inline bool can_is_canfd_skb(const struct sk_buff *skb)
{
/* the CAN specific type of skb is identified by its data length */
Expand Down

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