3.16.7-ckt19 -stable review patch. If anyone has any objections, please let me know.
------------------ From: Sabrina Dubroca <[email protected]> Without this length argument, we can read past the end of the iovec in memcpy_toiovec because we have no way of knowing the total length of the iovec's buffers. This is needed for stable kernels where 89c22d8c3b27 ("net: Fix skb csum races when peeking") has been backported but that don't have the ioviter conversion, which is almost all the stable trees <= 3.18. This also fixes a kernel crash for NFS servers when the client uses -onfsvers=3,proto=udp to mount the export. Signed-off-by: Sabrina Dubroca <[email protected]> Reviewed-by: Hannes Frederic Sowa <[email protected]> [ luis: backported to 3.16: - dropped changes to net/rxrpc/ar-recvmsg.c ] Signed-off-by: Luis Henriques <[email protected]> --- include/linux/skbuff.h | 2 +- net/core/datagram.c | 6 +++++- net/ipv4/tcp_input.c | 2 +- net/ipv4/udp.c | 2 +- net/ipv6/raw.c | 2 +- net/ipv6/udp.c | 3 ++- 6 files changed, 11 insertions(+), 6 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 010bc80be91c..94038f93f145 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -2525,7 +2525,7 @@ unsigned int datagram_poll(struct file *file, struct socket *sock, int skb_copy_datagram_iovec(const struct sk_buff *from, int offset, struct iovec *to, int size); int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb, int hlen, - struct iovec *iov); + struct iovec *iov, int len); int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset, const struct iovec *from, int from_offset, int len); diff --git a/net/core/datagram.c b/net/core/datagram.c index 3c69a464595e..169f742d1464 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -818,6 +818,7 @@ EXPORT_SYMBOL(__skb_checksum_complete); * @skb: skbuff * @hlen: hardware length * @iov: io vector + * @len: amount of data to copy from skb to iov * * Caller _must_ check that skb will fit to this iovec. * @@ -827,11 +828,14 @@ EXPORT_SYMBOL(__skb_checksum_complete); * can be modified! */ int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb, - int hlen, struct iovec *iov) + int hlen, struct iovec *iov, int len) { __wsum csum; int chunk = skb->len - hlen; + if (chunk > len) + chunk = len; + if (!chunk) return 0; diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 486f70050563..0cdaa633059b 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -4906,7 +4906,7 @@ static int tcp_copy_to_iovec(struct sock *sk, struct sk_buff *skb, int hlen) err = skb_copy_datagram_iovec(skb, hlen, tp->ucopy.iov, chunk); else err = skb_copy_and_csum_datagram_iovec(skb, hlen, - tp->ucopy.iov); + tp->ucopy.iov, chunk); if (!err) { tp->ucopy.len -= chunk; diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 10c1530ba978..4b9e4aba11b0 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1307,7 +1307,7 @@ try_again: else { err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), - msg->msg_iov); + msg->msg_iov, copied); if (err == -EINVAL) goto csum_copy_err; diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index b2dc60b0c764..fd377c4d8986 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -492,7 +492,7 @@ static int rawv6_recvmsg(struct kiocb *iocb, struct sock *sk, goto csum_copy_err; err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); } else { - err = skb_copy_and_csum_datagram_iovec(skb, 0, msg->msg_iov); + err = skb_copy_and_csum_datagram_iovec(skb, 0, msg->msg_iov, copied); if (err == -EINVAL) goto csum_copy_err; } diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index ad5891072a89..72603a9af4bc 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -428,7 +428,8 @@ try_again: err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov, copied); else { - err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov); + err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), + msg->msg_iov, copied); if (err == -EINVAL) goto csum_copy_err; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
