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author | Antonio Quartulli <ordex@autistici.org> | 2012-08-26 23:25:59 +0200 |
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committer | Antonio Quartulli <ordex@autistici.org> | 2012-10-29 09:42:45 +0100 |
commit | b8fcfa42e4ec5d55d4cccd5c728415e8bca0539d (patch) | |
tree | e4ebbf1372f4841b98b05276550db37b38f0abf7 | |
parent | 60c39c7584e1bb69cdce4e0a9ee1e78ba09c82b9 (diff) | |
download | linux-b8fcfa42e4ec5d55d4cccd5c728415e8bca0539d.tar.bz2 |
batman-adv: check for more space before accessing the skb
In batadv_check_unicast_ttvn() the code accesses both the unicast header and the
Ethernet header in the payload. For this reason pskb_may_pull() must be invoked
to check for the required space.
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
-rw-r--r-- | net/batman-adv/routing.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index 456a0a9f8831..46dd5b47ed29 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -908,8 +908,12 @@ static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv, bool tt_poss_change; int is_old_ttvn; - /* I could need to modify it */ - if (skb_cow(skb, sizeof(struct batadv_unicast_packet)) < 0) + /* check if there is enough data before accessing it */ + if (pskb_may_pull(skb, sizeof(*unicast_packet) + ETH_HLEN) < 0) + return 0; + + /* create a copy of the skb (in case of for re-routing) to modify it. */ + if (skb_cow(skb, sizeof(*unicast_packet)) < 0) return 0; unicast_packet = (struct batadv_unicast_packet *)skb->data; |