diff options
| author | Daniel Axtens <dja@axtens.net> | 2018-01-31 14:15:33 +1100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-11 12:24:10 +0200 |
| commit | a33b6d4c8bc7ba93f9d1dc77826724e4df8da662 (patch) | |
| tree | 08dd80b6e451af65c124413dddc4931500589587 /include/linux | |
| parent | c53c1a821d62eb8476425ebe79c0c0054ab45315 (diff) | |
net: create skb_gso_validate_mac_len()
commit 2b16f048729bf35e6c28a40cbfad07239f9dcd90 upstream.
If you take a GSO skb, and split it into packets, will the MAC
length (L2 + L3 + L4 headers + payload) of those packets be small
enough to fit within a given length?
Move skb_gso_mac_seglen() to skbuff.h with other related functions
like skb_gso_network_seglen() so we can use it, and then create
skb_gso_validate_mac_len to do the full calculation.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 4.4: There is no GSO_BY_FRAGS case to handle, so
skb_gso_validate_mac_len() becomes a trivial comparison. Put it inline in
<linux/skbuff.h>.]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/skbuff.h | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 502787c29ce9..a2f12d377d23 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -3664,5 +3664,35 @@ static inline unsigned int skb_gso_network_seglen(const struct sk_buff *skb) return hdr_len + skb_gso_transport_seglen(skb); } +/** + * skb_gso_mac_seglen - Return length of individual segments of a gso packet + * + * @skb: GSO skb + * + * skb_gso_mac_seglen is used to determine the real size of the + * individual segments, including MAC/L2, Layer3 (IP, IPv6) and L4 + * headers (TCP/UDP). + */ +static inline unsigned int skb_gso_mac_seglen(const struct sk_buff *skb) +{ + unsigned int hdr_len = skb_transport_header(skb) - skb_mac_header(skb); + return hdr_len + skb_gso_transport_seglen(skb); +} + +/** + * skb_gso_validate_mac_len - Will a split GSO skb fit in a given length? + * + * @skb: GSO skb + * @len: length to validate against + * + * skb_gso_validate_mac_len validates if a given skb will fit a wanted + * length once split, including L2, L3 and L4 headers and the payload. + */ +static inline bool +skb_gso_validate_mac_len(const struct sk_buff *skb, unsigned int len) +{ + return skb_gso_mac_seglen(skb) <= len; +} + #endif /* __KERNEL__ */ #endif /* _LINUX_SKBUFF_H */ |