linux-stable.git/net/ipv4, branch v5.4.263

ipv4: igmp: fix refcnt uaf issue when receiving igmp query packet

2023-12-08T07:44:27+00:00

[ Upstream commit e2b706c691905fe78468c361aaabc719d0a496f1 ]

When I perform the following test operations:
1.ip link add br0 type bridge
2.brctl addif br0 eth0
3.ip addr add 239.0.0.1/32 dev eth0
4.ip addr add 239.0.0.1/32 dev br0
5.ip addr add 224.0.0.1/32 dev br0
6.while ((1))
    do
        ifconfig br0 up
        ifconfig br0 down
    done
7.send IGMPv2 query packets to port eth0 continuously. For example,
./mausezahn ethX -c 0 "01 00 5e 00 00 01 00 72 19 88 aa 02 08 00 45 00 00
1c 00 01 00 00 01 02 0e 7f c0 a8 0a b7 e0 00 00 01 11 64 ee 9b 00 00 00 00"

The preceding tests may trigger the refcnt uaf issue of the mc list. The
stack is as follows:
	refcount_t: addition on 0; use-after-free.
	WARNING: CPU: 21 PID: 144 at lib/refcount.c:25 refcount_warn_saturate (lib/refcount.c:25)
	CPU: 21 PID: 144 Comm: ksoftirqd/21 Kdump: loaded Not tainted 6.7.0-rc1-next-20231117-dirty #80
	Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
	RIP: 0010:refcount_warn_saturate (lib/refcount.c:25)
	RSP: 0018:ffffb68f00657910 EFLAGS: 00010286
	RAX: 0000000000000000 RBX: ffff8a00c3bf96c0 RCX: ffff8a07b6160908
	RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffff8a07b6160900
	RBP: ffff8a00cba36862 R08: 0000000000000000 R09: 00000000ffff7fff
	R10: ffffb68f006577c0 R11: ffffffffb0fdcdc8 R12: ffff8a00c3bf9680
	R13: ffff8a00c3bf96f0 R14: 0000000000000000 R15: ffff8a00d8766e00
	FS:  0000000000000000(0000) GS:ffff8a07b6140000(0000) knlGS:0000000000000000
	CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
	CR2: 000055f10b520b28 CR3: 000000039741a000 CR4: 00000000000006f0
	Call Trace:
	
	igmp_heard_query (net/ipv4/igmp.c:1068)
	igmp_rcv (net/ipv4/igmp.c:1132)
	ip_protocol_deliver_rcu (net/ipv4/ip_input.c:205)
	ip_local_deliver_finish (net/ipv4/ip_input.c:234)
	__netif_receive_skb_one_core (net/core/dev.c:5529)
	netif_receive_skb_internal (net/core/dev.c:5729)
	netif_receive_skb (net/core/dev.c:5788)
	br_handle_frame_finish (net/bridge/br_input.c:216)
	nf_hook_bridge_pre (net/bridge/br_input.c:294)
	__netif_receive_skb_core (net/core/dev.c:5423)
	__netif_receive_skb_list_core (net/core/dev.c:5606)
	__netif_receive_skb_list (net/core/dev.c:5674)
	netif_receive_skb_list_internal (net/core/dev.c:5764)
	napi_gro_receive (net/core/gro.c:609)
	e1000_clean_rx_irq (drivers/net/ethernet/intel/e1000/e1000_main.c:4467)
	e1000_clean (drivers/net/ethernet/intel/e1000/e1000_main.c:3805)
	__napi_poll (net/core/dev.c:6533)
	net_rx_action (net/core/dev.c:6735)
	__do_softirq (kernel/softirq.c:554)
	run_ksoftirqd (kernel/softirq.c:913)
	smpboot_thread_fn (kernel/smpboot.c:164)
	kthread (kernel/kthread.c:388)
	ret_from_fork (arch/x86/kernel/process.c:153)
	ret_from_fork_asm (arch/x86/entry/entry_64.S:250)
	

The root causes are as follows:
Thread A					Thread B
...						netif_receive_skb
br_dev_stop					...
    br_multicast_leave_snoopers			...
        __ip_mc_dec_group			...
            __igmp_group_dropped		igmp_rcv
                igmp_stop_timer			    igmp_heard_query         //ref = 1
                ip_ma_put			        igmp_mod_timer
                    refcount_dec_and_test	            igmp_start_timer //ref = 0
			...                                     refcount_inc //ref increases from 0
When the device receives an IGMPv2 Query message, it starts the timer
immediately, regardless of whether the device is running. If the device is
down and has left the multicast group, it will cause the mc list refcount
uaf issue.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Zhengchao Shao 
Reviewed-by: Eric Dumazet 
Reviewed-by: Hangbin Liu 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

ipv4: Correct/silence an endian warning in __ip_do_redirect

2023-12-08T07:44:23+00:00

[ Upstream commit c0e2926266af3b5acf28df0a8fc6e4d90effe0bb ]

net/ipv4/route.c:783:46: warning: incorrect type in argument 2 (different base types)
net/ipv4/route.c:783:46:    expected unsigned int [usertype] key
net/ipv4/route.c:783:46:    got restricted __be32 [usertype] new_gw

Fixes: 969447f226b4 ("ipv4: use new_gw for redirect neigh lookup")
Suggested-by: Eric Dumazet 
Signed-off-by: Kunwu Chan 
Link: https://lore.kernel.org/r/20231119141759.420477-1-chentao@kylinos.cn
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

net: annotate data-races around sk->sk_dst_pending_confirm

2023-11-28T16:50:14+00:00

[ Upstream commit eb44ad4e635132754bfbcb18103f1dcb7058aedd ]

This field can be read or written without socket lock being held.

Add annotations to avoid load-store tearing.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

tcp: fix cookie_init_timestamp() overflows

2023-11-20T09:30:10+00:00

[ Upstream commit 73ed8e03388d16c12fc577e5c700b58a29045a15 ]

cookie_init_timestamp() is supposed to return a 64bit timestamp
suitable for both TSval determination and setting of skb->tstamp.

Unfortunately it uses 32bit fields and overflows after
2^32 * 10^6 nsec (~49 days) of uptime.

Generated TSval are still correct, but skb->tstamp might be set
far away in the past, potentially confusing other layers.

tcp_ns_to_ts() is changed to return a full 64bit value,
ts and ts_now variables are changed to u64 type,
and TSMASK is removed in favor of shifts operations.

While we are at it, change this sequence:
		ts >>= TSBITS;
		ts--;
		ts <<= TSBITS;
		ts |= options;
to:
		ts -= (1UL << TSBITS);

Fixes: 9a568de4818d ("tcp: switch TCP TS option (RFC 7323) to 1ms clock")
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

tcp: Remove one extra ktime_get_ns() from cookie_init_timestamp

2023-11-20T09:30:09+00:00

[ Upstream commit 200ecef67b8d09d16ec55f91c92751dcc7a38d40 ]

tcp_make_synack() already uses tcp_clock_ns(), and can pass
the value to cookie_init_timestamp() to avoid another call
to ktime_get_ns() helper.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Stable-dep-of: 73ed8e03388d ("tcp: fix cookie_init_timestamp() overflows")
Signed-off-by: Sasha Levin

tcp_metrics: do not create an entry from tcp_init_metrics()

2023-11-20T09:30:09+00:00

[ Upstream commit a135798e6e200ecb2f864cecca6d257ba278370c ]

tcp_init_metrics() only wants to get metrics if they were
previously stored in the cache. Creating an entry is adding
useless costs, especially when tcp_no_metrics_save is set.

Fixes: 51c5d0c4b169 ("tcp: Maintain dynamic metrics in local cache.")
Signed-off-by: Eric Dumazet 
Reviewed-by: David Ahern 
Acked-by: Neal Cardwell 
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

tcp_metrics: properly set tp->snd_ssthresh in tcp_init_metrics()

2023-11-20T09:30:09+00:00

[ Upstream commit 081480014a64a69d901f8ef1ffdd56d6085cf87e ]

We need to set tp->snd_ssthresh to TCP_INFINITE_SSTHRESH
in the case tcp_get_metrics() fails for some reason.

Fixes: 9ad7c049f0f7 ("tcp: RFC2988bis + taking RTT sample from 3WHS for the passive open side")
Signed-off-by: Eric Dumazet 
Reviewed-by: David Ahern 
Acked-by: Neal Cardwell 
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

tcp_metrics: add missing barriers on delete

2023-11-20T09:30:09+00:00

[ Upstream commit cbc3a153222805d65f821e10f4f78b6afce06f86 ]

When removing an item from RCU protected list, we must prevent
store-tearing, using rcu_assign_pointer() or WRITE_ONCE().

Fixes: 04f721c671656 ("tcp_metrics: Rewrite tcp_metrics_flush_all")
Signed-off-by: Eric Dumazet 
Reviewed-by: David Ahern 
Acked-by: Neal Cardwell 
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin

tcp: call tcp_try_undo_recovery when an RTOd TFO SYNACK is ACKed

2023-11-20T09:30:09+00:00

[ Upstream commit e326578a21414738de45f77badd332fb00bd0f58 ]

For passive TCP Fast Open sockets that had SYN/ACK timeout and did not
send more data in SYN_RECV, upon receiving the final ACK in 3WHS, the
congestion state may awkwardly stay in CA_Loss mode unless the CA state
was undone due to TCP timestamp checks. However, if
tcp_rcv_synrecv_state_fastopen() decides not to undo, then we should
enter CA_Open, because at that point we have received an ACK covering
the retransmitted SYNACKs. Currently, the icsk_ca_state is only set to
CA_Open after we receive an ACK for a data-packet. This is because
tcp_ack does not call tcp_fastretrans_alert (and tcp_process_loss) if
!prior_packets

Note that tcp_process_loss() calls tcp_try_undo_recovery(), so having
tcp_rcv_synrecv_state_fastopen() decide that if we're in CA_Loss we
should call tcp_try_undo_recovery() is consistent with that, and
low risk.

Fixes: dad8cea7add9 ("tcp: fix TFO SYNACK undo to avoid double-timestamp-undo")
Signed-off-by: Aananth V 
Signed-off-by: Neal Cardwell 
Signed-off-by: Yuchung Cheng 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

tcp: fix wrong RTO timeout when received SACK reneging

2023-11-08T10:23:36+00:00

[ Upstream commit d2a0fc372aca561556e765d0a9ec365c7c12f0ad ]

This commit fix wrong RTO timeout when received SACK reneging.

When an ACK arrived pointing to a SACK reneging, tcp_check_sack_reneging()
will rearm the RTO timer for min(1/2*srtt, 10ms) into to the future.

But since the commit 62d9f1a6945b ("tcp: fix TLP timer not set when
CA_STATE changes from DISORDER to OPEN") merged, the tcp_set_xmit_timer()
is moved after tcp_fastretrans_alert()(which do the SACK reneging check),
so the RTO timeout will be overwrited by tcp_set_xmit_timer() with
icsk_rto instead of 1/2*srtt.

Here is a packetdrill script to check this bug:
0     socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
+0    bind(3, ..., ...) = 0
+0    listen(3, 1) = 0

// simulate srtt to 100ms
+0    < S 0:0(0) win 32792 
+0    > S. 0:0(0) ack 1 
+.1    < . 1:1(0) ack 1 win 1024

+0    accept(3, ..., ...) = 4

+0    write(4, ..., 10000) = 10000
+0    > P. 1:10001(10000) ack 1

// inject sack
+.1    < . 1:1(0) ack 1 win 257 
+0    > . 1:1001(1000) ack 1

// inject sack reneging
+.1    < . 1:1(0) ack 1001 win 257 

// we expect rto fired in 1/2*srtt (50ms)
+.05    > . 1001:2001(1000) ack 1

This fix remove the FLAG_SET_XMIT_TIMER from ack_flag when
tcp_check_sack_reneging() set RTO timer with 1/2*srtt to avoid
being overwrited later.

Fixes: 62d9f1a6945b ("tcp: fix TLP timer not set when CA_STATE changes from DISORDER to OPEN")
Signed-off-by: Fred Chen 
Reviewed-by: Neal Cardwell 
Tested-by: Neal Cardwell 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin