Commit 80f1a0f4e0cd ("net/ipv6: Put lwtstate when destroying fib6_info")
partially fixed the kmemleak [1], lwtstate can be copied from fib6_info,
with ip6_rt_copy_init(), and it should be done only once there.
rt->dst.lwtstate is set by ip6_rt_init_dst(), at the start of the function
ip6_rt_copy_init(), so there is no need to get it again at the end.
With this patch, lwtstate also isn't copied from RTF_REJECT routes.
[1]:
unreferenced object 0xffff880b6aaa14e0 (size 64):
comm "ip", pid 10577, jiffies 4295149341 (age 1273.903s)
hex dump (first 32 bytes):
01 00 04 00 04 00 00 00 10 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<0000000018664623>] lwtunnel_build_state+0x1bc/0x420
[<00000000b73aa29a>] ip6_route_info_create+0x9f7/0x1fd0
[<00000000ee2c5d1f>] ip6_route_add+0x14/0x70
[<000000008537b55c>] inet6_rtm_newroute+0xd9/0xe0
[<000000002acc50f5>] rtnetlink_rcv_msg+0x66f/0x8e0
[<000000008d9cd381>] netlink_rcv_skb+0x268/0x3b0
[<000000004c893c76>] netlink_unicast+0x417/0x5a0
[<00000000f2ab1afb>] netlink_sendmsg+0x70b/0xc30
[<00000000890ff0aa>] sock_sendmsg+0xb1/0xf0
[<00000000a2e7b66f>] ___sys_sendmsg+0x659/0x950
[<000000001e7426c8>] __sys_sendmsg+0xde/0x170
[<00000000fe411443>] do_syscall_64+0x9f/0x4a0
[<000000001be7b28b>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[<000000006d21f353>] 0xffffffffffffffff
Fixes: 6edb3c96a5f0 ("net/ipv6: Defer initialization of dst to data path")
Signed-off-by: Alexey Kodanev <redacted>
---
net/ipv6/route.c | 1 -
1 file changed, 1 deletion(-)
From: David Ahern <hidden> Date: 2018-08-30 20:13:27
On 8/30/18 10:11 AM, Alexey Kodanev wrote:
Commit 80f1a0f4e0cd ("net/ipv6: Put lwtstate when destroying fib6_info")
partially fixed the kmemleak [1], lwtstate can be copied from fib6_info,
with ip6_rt_copy_init(), and it should be done only once there.
rt->dst.lwtstate is set by ip6_rt_init_dst(), at the start of the function
ip6_rt_copy_init(), so there is no need to get it again at the end.
With this patch, lwtstate also isn't copied from RTF_REJECT routes.
What test did you run to uncover this? Curious as to why my testing that
found the need for 80f1a0f4e0cd did not hit this.
I was using IPv6 route with MPLS. Will submit MPLS tests to LTP soon,
they will include that test as well.
Meanwhile, these commands below are able to trigger it:
ip route add $new_route encap mpls 50 via inet6 $ip_rhost
ping6 $ip_new_route
ip route del $new_route
Thanks,
Alexey
Commit 80f1a0f4e0cd ("net/ipv6: Put lwtstate when destroying fib6_info")
partially fixed the kmemleak [1], lwtstate can be copied from fib6_info,
with ip6_rt_copy_init(), and it should be done only once there.
rt->dst.lwtstate is set by ip6_rt_init_dst(), at the start of the function
ip6_rt_copy_init(), so there is no need to get it again at the end.
With this patch, lwtstate also isn't copied from RTF_REJECT routes.
...
Fixes: 6edb3c96a5f0 ("net/ipv6: Defer initialization of dst to data path")
Signed-off-by: Alexey Kodanev <redacted>