xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

drivers/net, ipv6: Select IPv6 fragment idents for virtio UFO packets

Browse Source 
UFO is now disabled on all drivers that work with virtio net headers,
but userland may try to send UFO/IPv6 packets anyway.  Instead of
sending with ID=0, we should select identifiers on their behalf (as we
used to).

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 916e4cf46d ("ipv6: reuse ip6_frag_id from ip6_ufo_append_data")
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ben Hutchings
2014-10-30 18:27:17 +00:00
committed by David S. Miller
parent 3d0ad09412
commit 5188cd44c5
4 changed files with 44 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

34
net/ipv6/output_core.c
View File

@@ -3,11 +3,45 @@
* not configured or static. These functions are needed by GSO/GRO implementation.
*/
#include <linux/export.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/ip6_fib.h>
#include <net/addrconf.h>
#include <net/secure_seq.h>
/* This function exists only for tap drivers that must support broken
* clients requesting UFO without specifying an IPv6 fragment ID.
*
* This is similar to ipv6_select_ident() but we use an independent hash
* seed to limit information leakage.
*
* The network header must be set before calling this.
*/
void ipv6_proxy_select_ident(struct sk_buff *skb)
{
static u32 ip6_proxy_idents_hashrnd __read_mostly;
struct in6_addr buf[2];
struct in6_addr *addrs;
u32 hash, id;
addrs = skb_header_pointer(skb,
skb_network_offset(skb) +
offsetof(struct ipv6hdr, saddr),
sizeof(buf), buf);
if (!addrs)
return;
net_get_random_once(&ip6_proxy_idents_hashrnd,
sizeof(ip6_proxy_idents_hashrnd));
hash = __ipv6_addr_jhash(&addrs[1], ip6_proxy_idents_hashrnd);
hash = __ipv6_addr_jhash(&addrs[0], hash);
id = ip_idents_reserve(hash, 1);
skb_shinfo(skb)->ip6_frag_id = htonl(id);
}
EXPORT_SYMBOL_GPL(ipv6_proxy_select_ident);
int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr)
{
u16 offset = sizeof(struct ipv6hdr);