[PATCH 4.14 60/70] bonding: set dev->needed_headroom in bond_setup_by_slave()
From: Greg Kroah-Hartman
Date: Mon Oct 12 2020 - 10:03:10 EST
From: Eric Dumazet <edumazet@xxxxxxxxxx>
[ Upstream commit f32f19339596b214c208c0dba716f4b6cc4f6958 ]
syzbot managed to crash a host by creating a bond
with a GRE device.
For non Ethernet device, bonding calls bond_setup_by_slave()
instead of ether_setup(), and unfortunately dev->needed_headroom
was not copied from the new added member.
[ 171.243095] skbuff: skb_under_panic: text:ffffffffa184b9ea len:116 put:20 head:ffff883f84012dc0 data:ffff883f84012dbc tail:0x70 end:0xd00 dev:bond0
[ 171.243111] ------------[ cut here ]------------
[ 171.243112] kernel BUG at net/core/skbuff.c:112!
[ 171.243117] invalid opcode: 0000 [#1] SMP KASAN PTI
[ 171.243469] gsmi: Log Shutdown Reason 0x03
[ 171.243505] Call Trace:
[ 171.243506] <IRQ>
[ 171.243512] [<ffffffffa171be59>] skb_push+0x49/0x50
[ 171.243516] [<ffffffffa184b9ea>] ipgre_header+0x2a/0xf0
[ 171.243520] [<ffffffffa17452d7>] neigh_connected_output+0xb7/0x100
[ 171.243524] [<ffffffffa186f1d3>] ip6_finish_output2+0x383/0x490
[ 171.243528] [<ffffffffa186ede2>] __ip6_finish_output+0xa2/0x110
[ 171.243531] [<ffffffffa186acbc>] ip6_finish_output+0x2c/0xa0
[ 171.243534] [<ffffffffa186abe9>] ip6_output+0x69/0x110
[ 171.243537] [<ffffffffa186ac90>] ? ip6_output+0x110/0x110
[ 171.243541] [<ffffffffa189d952>] mld_sendpack+0x1b2/0x2d0
[ 171.243544] [<ffffffffa189d290>] ? mld_send_report+0xf0/0xf0
[ 171.243548] [<ffffffffa189c797>] mld_ifc_timer_expire+0x2d7/0x3b0
[ 171.243551] [<ffffffffa189c4c0>] ? mld_gq_timer_expire+0x50/0x50
[ 171.243556] [<ffffffffa0fea270>] call_timer_fn+0x30/0x130
[ 171.243559] [<ffffffffa0fea17c>] expire_timers+0x4c/0x110
[ 171.243563] [<ffffffffa0fea0e3>] __run_timers+0x213/0x260
[ 171.243566] [<ffffffffa0fecb7d>] ? ktime_get+0x3d/0xa0
[ 171.243570] [<ffffffffa0ff9c4e>] ? clockevents_program_event+0x7e/0xe0
[ 171.243574] [<ffffffffa0f7e5d5>] ? sched_clock_cpu+0x15/0x190
[ 171.243577] [<ffffffffa0fe973d>] run_timer_softirq+0x1d/0x40
[ 171.243581] [<ffffffffa1c00152>] __do_softirq+0x152/0x2f0
[ 171.243585] [<ffffffffa0f44e1f>] irq_exit+0x9f/0xb0
[ 171.243588] [<ffffffffa1a02e1d>] smp_apic_timer_interrupt+0xfd/0x1a0
[ 171.243591] [<ffffffffa1a01ea6>] apic_timer_interrupt+0x86/0x90
Fixes: f5184d267c1a ("net: Allow netdevices to specify needed head/tailroom")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/bonding/bond_main.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 861d2c0a521a4..6aaf1196d9a55 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1129,6 +1129,7 @@ static void bond_setup_by_slave(struct net_device *bond_dev,
bond_dev->type = slave_dev->type;
bond_dev->hard_header_len = slave_dev->hard_header_len;
+ bond_dev->needed_headroom = slave_dev->needed_headroom;
bond_dev->addr_len = slave_dev->addr_len;
memcpy(bond_dev->broadcast, slave_dev->broadcast,
--
2.25.1