path: root/net
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authorDaniel Borkmann <dborkman@redhat.com>2013-06-12 16:02:27 +0200
committerDavid S. Miller <davem@davemloft.net>2013-06-13 01:38:36 -0700
commit2dc85bf323515e59e15dfa858d1472bb25cad0fe (patch)
tree48d2bb80d960a20a12ebb2b5108c3e589605e26b /net
parent631f24a2febb228f82604dc5330091e8080cd8ae (diff)
packet: packet_getname_spkt: make sure string is always 0-terminated
uaddr->sa_data is exactly of size 14, which is hard-coded here and passed as a size argument to strncpy(). A device name can be of size IFNAMSIZ (== 16), meaning we might leave the destination string unterminated. Thus, use strlcpy() and also sizeof() while we're at it. We need to memset the data area beforehand, since strlcpy does not padd the remaining buffer with zeroes for user space, so that we do not possibly leak anything. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
1 files changed, 2 insertions, 3 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 8ec1bca7f859..20a1bd0e6549 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -2851,12 +2851,11 @@ static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
uaddr->sa_family = AF_PACKET;
+ memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
if (dev)
- strncpy(uaddr->sa_data, dev->name, 14);
- else
- memset(uaddr->sa_data, 0, 14);
+ strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
*uaddr_len = sizeof(*uaddr);

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