From: Willem de Bruijn <will...@google.com>
Packet sockets with SOCK_DGRAM may pass an address for use in
dev_hard_header. Ensure that it is of sufficient length.
Reported-by: syzbot <syzkal...@googlegroups.com>
Signed-off-by: Willem de Bruijn <will...@google.com>
---
net/packet/af_packet.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 6655793765b2d..5dda263b4a0a1 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -2627,6 +2627,8 @@ static int tpacket_snd(struct packet_sock *po, struct
msghdr *msg)
proto = saddr->sll_protocol;
addr = saddr->sll_addr;
dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
+ if (addr && dev && saddr->sll_halen < dev->addr_len)
+ goto out;
}
err = -ENXIO;
@@ -2825,6 +2827,8 @@ static int packet_snd(struct socket *sock, struct msghdr
*msg, size_t len)
proto = saddr->sll_protocol;
addr = saddr->sll_addr;
dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
+ if (addr && dev && saddr->sll_halen < dev->addr_len)
+ goto out;
}
err = -ENXIO;
--
2.20.1.415.g653613c723-goog
