diff options
author | Amerigo Wang <amwang@redhat.com> | 2012-10-09 17:48:16 +0000 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2012-10-30 23:26:43 +0000 |
commit | fe54b1e7efb9b0c4bc0be5202c50639cd7571c8e (patch) | |
tree | 13df578445c2724553a38ab6cf34f4a4d15a64b3 /net/core | |
parent | 6780e9e1d9f227fc2cf1ff966f43a5d794086e79 (diff) |
pktgen: fix crash when generating IPv6 packets
commit 5aa8b572007c4bca1e6d3dd4c4820f1ae49d6bb2 upstream.
For IPv6, sizeof(struct ipv6hdr) = 40, thus the following
expression will result negative:
datalen = pkt_dev->cur_pkt_size - 14 -
sizeof(struct ipv6hdr) - sizeof(struct udphdr) -
pkt_dev->pkt_overhead;
And, the check "if (datalen < sizeof(struct pktgen_hdr))" will be
passed as "datalen" is promoted to unsigned, therefore will cause
a crash later.
This is a quick fix by checking if "datalen" is negative. The following
patch will increase the default value of 'min_pkt_size' for IPv6.
This bug should exist for a long time, so Cc -stable too.
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'net/core')
-rw-r--r-- | net/core/pktgen.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/core/pktgen.c b/net/core/pktgen.c index df878de7c6e..7bc9991f16f 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -2935,7 +2935,7 @@ static struct sk_buff *fill_packet_ipv6(struct net_device *odev, sizeof(struct ipv6hdr) - sizeof(struct udphdr) - pkt_dev->pkt_overhead; - if (datalen < sizeof(struct pktgen_hdr)) { + if (datalen < 0 || datalen < sizeof(struct pktgen_hdr)) { datalen = sizeof(struct pktgen_hdr); if (net_ratelimit()) pr_info("increased datalen to %d\n", datalen); |