From: Herbert Xu herbert@gondor.apana.org.au
commit cb3e9864cdbe35ff6378966660edbcbac955fe17 upstream.
The total cork length created by ip6_append_data includes extension headers, so we must exclude them when comparing them against the IPV6_CHECKSUM offset which does not include extension headers.
Reported-by: Kyle Zeng zengyhkyle@gmail.com Fixes: 357b40a18b04 ("[IPV6]: IPV6_CHECKSUM socket option can corrupt kernel memory") Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv6/raw.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -539,6 +539,7 @@ csum_copy_err: static int rawv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6, struct raw6_sock *rp) { + struct ipv6_txoptions *opt; struct sk_buff *skb; int err = 0; int offset; @@ -556,6 +557,9 @@ static int rawv6_push_pending_frames(str
offset = rp->offset; total_len = inet_sk(sk)->cork.base.length; + opt = inet6_sk(sk)->cork.opt; + total_len -= opt ? opt->opt_flen : 0; + if (offset >= total_len - 1) { err = -EINVAL; ip6_flush_pending_frames(sk);