diff options
| author | Miaohe Lin <linmiaohe@huawei.com> | 2019-03-11 16:29:32 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-03-11 10:32:45 -0700 |
| commit | a843dc4ebaecd15fca1f4d35a97210f72ea1473b (patch) | |
| tree | afb112dfd67771948e05c5b04d3db80029ee35dd | |
| parent | 2a5ff07a0eb945f291e361aa6f6becca8340ba46 (diff) | |
| download | linux-a843dc4ebaecd15fca1f4d35a97210f72ea1473b.tar.bz2 | |
net: sit: fix UBSAN Undefined behaviour in check_6rd
In func check_6rd,tunnel->ip6rd.relay_prefixlen may equal to
32,so UBSAN complain about it.
UBSAN: Undefined behaviour in net/ipv6/sit.c:781:47
shift exponent 32 is too large for 32-bit type 'unsigned int'
CPU: 6 PID: 20036 Comm: syz-executor.0 Not tainted 4.19.27 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1
04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xca/0x13e lib/dump_stack.c:113
ubsan_epilogue+0xe/0x81 lib/ubsan.c:159
__ubsan_handle_shift_out_of_bounds+0x293/0x2e8 lib/ubsan.c:425
check_6rd.constprop.9+0x433/0x4e0 net/ipv6/sit.c:781
try_6rd net/ipv6/sit.c:806 [inline]
ipip6_tunnel_xmit net/ipv6/sit.c:866 [inline]
sit_tunnel_xmit+0x141c/0x2720 net/ipv6/sit.c:1033
__netdev_start_xmit include/linux/netdevice.h:4300 [inline]
netdev_start_xmit include/linux/netdevice.h:4309 [inline]
xmit_one net/core/dev.c:3243 [inline]
dev_hard_start_xmit+0x17c/0x780 net/core/dev.c:3259
__dev_queue_xmit+0x1656/0x2500 net/core/dev.c:3829
neigh_output include/net/neighbour.h:501 [inline]
ip6_finish_output2+0xa36/0x2290 net/ipv6/ip6_output.c:120
ip6_finish_output+0x3e7/0xa20 net/ipv6/ip6_output.c:154
NF_HOOK_COND include/linux/netfilter.h:278 [inline]
ip6_output+0x1e2/0x720 net/ipv6/ip6_output.c:171
dst_output include/net/dst.h:444 [inline]
ip6_local_out+0x99/0x170 net/ipv6/output_core.c:176
ip6_send_skb+0x9d/0x2f0 net/ipv6/ip6_output.c:1697
ip6_push_pending_frames+0xc0/0x100 net/ipv6/ip6_output.c:1717
rawv6_push_pending_frames net/ipv6/raw.c:616 [inline]
rawv6_sendmsg+0x2435/0x3530 net/ipv6/raw.c:946
inet_sendmsg+0xf8/0x5c0 net/ipv4/af_inet.c:798
sock_sendmsg_nosec net/socket.c:621 [inline]
sock_sendmsg+0xc8/0x110 net/socket.c:631
___sys_sendmsg+0x6cf/0x890 net/socket.c:2114
__sys_sendmsg+0xf0/0x1b0 net/socket.c:2152
do_syscall_64+0xc8/0x580 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Signed-off-by: linmiaohe <linmiaohe@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv6/sit.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index 09e440e8dfae..07e21a82ce4c 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -778,8 +778,9 @@ static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst, pbw0 = tunnel->ip6rd.prefixlen >> 5; pbi0 = tunnel->ip6rd.prefixlen & 0x1f; - d = (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >> - tunnel->ip6rd.relay_prefixlen; + d = tunnel->ip6rd.relay_prefixlen < 32 ? + (ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >> + tunnel->ip6rd.relay_prefixlen : 0; pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen; if (pbi1 > 0) |