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author | Daniel Axtens <dja@axtens.net> | 2019-02-14 11:31:17 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-02-20 10:20:48 +0100 |
commit | 785644d6731914407b87e70db00aca351a44a935 (patch) | |
tree | 584631289f55fcbd4d1c1726cc98300b6f9954dd /include | |
parent | dee92bc8c2761373b88f67bba87393ac50d8ceda (diff) | |
download | linux-stable-785644d6731914407b87e70db00aca351a44a935.tar.gz linux-stable-785644d6731914407b87e70db00aca351a44a935.tar.bz2 linux-stable-785644d6731914407b87e70db00aca351a44a935.zip |
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>
[jwang: cherry pick for CVE-2018-1000026]
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/skbuff.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 39c2570ddcf6..50a4a5968f3a 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -3317,6 +3317,7 @@ int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen); void skb_scrub_packet(struct sk_buff *skb, bool xnet); unsigned int skb_gso_transport_seglen(const struct sk_buff *skb); bool skb_gso_validate_mtu(const struct sk_buff *skb, unsigned int mtu); +bool skb_gso_validate_mac_len(const struct sk_buff *skb, unsigned int len); struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t features); struct sk_buff *skb_vlan_untag(struct sk_buff *skb); int skb_ensure_writable(struct sk_buff *skb, int write_len); @@ -4087,6 +4088,21 @@ 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); +} + /* Local Checksum Offload. * Compute outer checksum based on the assumption that the * inner checksum will be offloaded later. |