diff options
| author | Yue Haibing <yuehaibing@huawei.com> | 2023-08-01 14:43:18 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2023-08-02 10:35:21 +0100 |
| commit | 30e0191b16e8a58e4620fa3e2839ddc7b9d4281c (patch) | |
| tree | ef66f04d25694ab5bda4f5f53b2a37d4b8a2ee9d /net/ipv6 | |
| parent | 1cfef80d4c2b2c599189f36f36320b205d9447d9 (diff) | |
ip6mr: Fix skb_under_panic in ip6mr_cache_report()
skbuff: skb_under_panic: text:ffffffff88771f69 len:56 put:-4
head:ffff88805f86a800 data:ffff887f5f86a850 tail:0x88 end:0x2c0 dev:pim6reg
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:192!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 2 PID: 22968 Comm: kworker/2:11 Not tainted 6.5.0-rc3-00044-g0a8db05b571a #236
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:skb_panic+0x152/0x1d0
Call Trace:
<TASK>
skb_push+0xc4/0xe0
ip6mr_cache_report+0xd69/0x19b0
reg_vif_xmit+0x406/0x690
dev_hard_start_xmit+0x17e/0x6e0
__dev_queue_xmit+0x2d6a/0x3d20
vlan_dev_hard_start_xmit+0x3ab/0x5c0
dev_hard_start_xmit+0x17e/0x6e0
__dev_queue_xmit+0x2d6a/0x3d20
neigh_connected_output+0x3ed/0x570
ip6_finish_output2+0x5b5/0x1950
ip6_finish_output+0x693/0x11c0
ip6_output+0x24b/0x880
NF_HOOK.constprop.0+0xfd/0x530
ndisc_send_skb+0x9db/0x1400
ndisc_send_rs+0x12a/0x6c0
addrconf_dad_completed+0x3c9/0xea0
addrconf_dad_work+0x849/0x1420
process_one_work+0xa22/0x16e0
worker_thread+0x679/0x10c0
ret_from_fork+0x28/0x60
ret_from_fork_asm+0x11/0x20
When setup a vlan device on dev pim6reg, DAD ns packet may sent on reg_vif_xmit().
reg_vif_xmit()
ip6mr_cache_report()
skb_push(skb, -skb_network_offset(pkt));//skb_network_offset(pkt) is 4
And skb_push declared as:
void *skb_push(struct sk_buff *skb, unsigned int len);
skb->data -= len;
//0xffff88805f86a84c - 0xfffffffc = 0xffff887f5f86a850
skb->data is set to 0xffff887f5f86a850, which is invalid mem addr, lead to skb_push() fails.
Fixes: 14fb64e1f449 ("[IPV6] MROUTE: Support PIM-SM (SSM).")
Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/ip6mr.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c index cc3d5ad17257..67a3b8f6e72b 100644 --- a/net/ipv6/ip6mr.c +++ b/net/ipv6/ip6mr.c @@ -1073,7 +1073,7 @@ static int ip6mr_cache_report(const struct mr_table *mrt, struct sk_buff *pkt, And all this only to mangle msg->im6_msgtype and to set msg->im6_mbz to "mbz" :-) */ - skb_push(skb, -skb_network_offset(pkt)); + __skb_pull(skb, skb_network_offset(pkt)); skb_push(skb, sizeof(*msg)); skb_reset_transport_header(skb); |