diff options
| author | Eric Dumazet <eric.dumazet@gmail.com> | 2011-06-06 22:42:06 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2011-06-06 22:42:06 -0700 |
| commit | 13fcb7bd322164c67926ffe272846d4860196dc6 (patch) | |
| tree | aa7727f84e4ce2a2b1cf758e03d176c62354f44b | |
| parent | 79b3891587741dfac72cdfead1f2764b56a567b0 (diff) | |
af_packet: prevent information leak
In 2.6.27, commit 393e52e33c6c2 (packet: deliver VLAN TCI to userspace)
added a small information leak.
Add padding field and make sure its zeroed before copy to user.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/linux/if_packet.h | 2 | ||||
| -rw-r--r-- | net/packet/af_packet.c | 2 |
2 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/if_packet.h b/include/linux/if_packet.h index 6d66ce1791a9..7b318630139f 100644 --- a/include/linux/if_packet.h +++ b/include/linux/if_packet.h @@ -62,6 +62,7 @@ struct tpacket_auxdata { __u16 tp_mac; __u16 tp_net; __u16 tp_vlan_tci; + __u16 tp_padding; }; /* Rx ring - header status */ @@ -101,6 +102,7 @@ struct tpacket2_hdr { __u32 tp_sec; __u32 tp_nsec; __u16 tp_vlan_tci; + __u16 tp_padding; }; #define TPACKET2_HDRLEN (TPACKET_ALIGN(sizeof(struct tpacket2_hdr)) + sizeof(struct sockaddr_ll)) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index ba248d93399a..c0c3cda19712 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -804,6 +804,7 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, } else { h.h2->tp_vlan_tci = 0; } + h.h2->tp_padding = 0; hdrlen = sizeof(*h.h2); break; default: @@ -1736,6 +1737,7 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock, } else { aux.tp_vlan_tci = 0; } + aux.tp_padding = 0; put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux); } |