Commit Graph

60468 Commits

Author SHA1 Message Date
John Fastabend
b4b89b7b2d bpf: sockmap, updating the sg structure should also update curr
[ Upstream commit bb9aefde5bbaf6c168c77ba635c155b4980c2287 ]

Curr pointer should be updated when the sg structure is shifted.

Fixes: 7246d8ed4d ("bpf: helper to pop data from messages")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20231206232706.374377-3-john.fastabend@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13 18:18:13 +01:00
Eric Dumazet
7ffff0cc92 tcp: do not accept ACK of bytes we never sent
[ Upstream commit 3d501dd326fb1c73f1b8206d4c6e1d7b15c07e27 ]

This patch is based on a detailed report and ideas from Yepeng Pan
and Christian Rossow.

ACK seq validation is currently following RFC 5961 5.2 guidelines:

   The ACK value is considered acceptable only if
   it is in the range of ((SND.UNA - MAX.SND.WND) <= SEG.ACK <=
   SND.NXT).  All incoming segments whose ACK value doesn't satisfy the
   above condition MUST be discarded and an ACK sent back.  It needs to
   be noted that RFC 793 on page 72 (fifth check) says: "If the ACK is a
   duplicate (SEG.ACK < SND.UNA), it can be ignored.  If the ACK
   acknowledges something not yet sent (SEG.ACK > SND.NXT) then send an
   ACK, drop the segment, and return".  The "ignored" above implies that
   the processing of the incoming data segment continues, which means
   the ACK value is treated as acceptable.  This mitigation makes the
   ACK check more stringent since any ACK < SND.UNA wouldn't be
   accepted, instead only ACKs that are in the range ((SND.UNA -
   MAX.SND.WND) <= SEG.ACK <= SND.NXT) get through.

This can be refined for new (and possibly spoofed) flows,
by not accepting ACK for bytes that were never sent.

This greatly improves TCP security at a little cost.

I added a Fixes: tag to make sure this patch will reach stable trees,
even if the 'blamed' patch was adhering to the RFC.

tp->bytes_acked was added in linux-4.2

Following packetdrill test (courtesy of Yepeng Pan) shows
the issue at hand:

0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
+0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+0 bind(3, ..., ...) = 0
+0 listen(3, 1024) = 0

// ---------------- Handshake ------------------- //

// when window scale is set to 14 the window size can be extended to
// 65535 * (2^14) = 1073725440. Linux would accept an ACK packet
// with ack number in (Server_ISN+1-1073725440. Server_ISN+1)
// ,though this ack number acknowledges some data never
// sent by the server.

+0 < S 0:0(0) win 65535 <mss 1400,nop,wscale 14>
+0 > S. 0:0(0) ack 1 <...>
+0 < . 1:1(0) ack 1 win 65535
+0 accept(3, ..., ...) = 4

// For the established connection, we send an ACK packet,
// the ack packet uses ack number 1 - 1073725300 + 2^32,
// where 2^32 is used to wrap around.
// Note: we used 1073725300 instead of 1073725440 to avoid possible
// edge cases.
// 1 - 1073725300 + 2^32 = 3221241997

// Oops, old kernels happily accept this packet.
+0 < . 1:1001(1000) ack 3221241997 win 65535

// After the kernel fix the following will be replaced by a challenge ACK,
// and prior malicious frame would be dropped.
+0 > . 1:1(0) ack 1001

Fixes: 354e4aa391 ("tcp: RFC 5961 5.2 Blind Data Injection Attack Mitigation")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Yepeng Pan <yepeng.pan@cispa.de>
Reported-by: Christian Rossow <rossow@cispa.de>
Acked-by: Neal Cardwell <ncardwell@google.com>
Link: https://lore.kernel.org/r/20231205161841.2702925-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13 18:18:12 +01:00
Phil Sutter
69431f609b netfilter: xt_owner: Fix for unsafe access of sk->sk_socket
[ Upstream commit 7ae836a3d630e146b732fe8ef7d86b243748751f ]

A concurrently running sock_orphan() may NULL the sk_socket pointer in
between check and deref. Follow other users (like nft_meta.c for
instance) and acquire sk_callback_lock before dereferencing sk_socket.

Fixes: 0265ab44ba ("[NETFILTER]: merge ipt_owner/ip6t_owner in xt_owner")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13 18:18:12 +01:00
Shigeru Yoshida
1ec21fde58 ipv4: ip_gre: Avoid skb_pull() failure in ipgre_xmit()
[ Upstream commit 80d875cfc9d3711a029f234ef7d680db79e8fa4b ]

In ipgre_xmit(), skb_pull() may fail even if pskb_inet_may_pull() returns
true. For example, applications can use PF_PACKET to create a malformed
packet with no IP header. This type of packet causes a problem such as
uninit-value access.

This patch ensures that skb_pull() can pull the required size by checking
the skb with pskb_network_may_pull() before skb_pull().

Fixes: c544193214 ("GRE: Refactor GRE tunneling code.")
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Suman Ghosh <sumang@marvell.com>
Link: https://lore.kernel.org/r/20231202161441.221135-1-syoshida@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13 18:18:12 +01:00
Eric Dumazet
be1ab8bf05 ipv6: fix potential NULL deref in fib6_add()
[ Upstream commit 75475bb51e78a3f54ad2f69380f2a1c985e85f2d ]

If fib6_find_prefix() returns NULL, we should silently fallback
using fib6_null_entry regardless of RT6_DEBUG value.

syzbot reported:

WARNING: CPU: 0 PID: 5477 at net/ipv6/ip6_fib.c:1516 fib6_add+0x310d/0x3fa0 net/ipv6/ip6_fib.c:1516
Modules linked in:
CPU: 0 PID: 5477 Comm: syz-executor.0 Not tainted 6.7.0-rc2-syzkaller-00029-g9b6de136b5f0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
RIP: 0010:fib6_add+0x310d/0x3fa0 net/ipv6/ip6_fib.c:1516
Code: 00 48 8b 54 24 68 e8 42 22 00 00 48 85 c0 74 14 49 89 c6 e8 d5 d3 c2 f7 eb 5d e8 ce d3 c2 f7 e9 ca 00 00 00 e8 c4 d3 c2 f7 90 <0f> 0b 90 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 38 80 3c 01 00
RSP: 0018:ffffc90005067740 EFLAGS: 00010293
RAX: ffffffff89cba5bc RBX: ffffc90005067ab0 RCX: ffff88801a2e9dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90005067980 R08: ffffffff89cbca85 R09: 1ffff110040d4b85
R10: dffffc0000000000 R11: ffffed10040d4b86 R12: 00000000ffffffff
R13: 1ffff110051c3904 R14: ffff8880206a5c00 R15: ffff888028e1c820
FS: 00007f763783c6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f763783bff8 CR3: 000000007f74d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__ip6_ins_rt net/ipv6/route.c:1303 [inline]
ip6_route_add+0x88/0x120 net/ipv6/route.c:3847
ipv6_route_ioctl+0x525/0x7b0 net/ipv6/route.c:4467
inet6_ioctl+0x21a/0x270 net/ipv6/af_inet6.c:575
sock_do_ioctl+0x152/0x460 net/socket.c:1220
sock_ioctl+0x615/0x8c0 net/socket.c:1339
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x45/0x110 arch/x86/entry/common.c:82

Fixes: 7bbfe00e02 ("ipv6: fix general protection fault in fib6_add()")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Wei Wang <weiwan@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20231129160630.3509216-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13 18:18:11 +01:00
Jozsef Kadlecsik
427deb5ba5 netfilter: ipset: fix race condition between swap/destroy and kernel side add/del/test
[ Upstream commit 28628fa952fefc7f2072ce6e8016968cc452b1ba ]

Linkui Xiao reported that there's a race condition when ipset swap and destroy is
called, which can lead to crash in add/del/test element operations. Swap then
destroy are usual operations to replace a set with another one in a production
system. The issue can in some cases be reproduced with the script:

ipset create hash_ip1 hash:net family inet hashsize 1024 maxelem 1048576
ipset add hash_ip1 172.20.0.0/16
ipset add hash_ip1 192.168.0.0/16
iptables -A INPUT -m set --match-set hash_ip1 src -j ACCEPT
while [ 1 ]
do
	# ... Ongoing traffic...
        ipset create hash_ip2 hash:net family inet hashsize 1024 maxelem 1048576
        ipset add hash_ip2 172.20.0.0/16
        ipset swap hash_ip1 hash_ip2
        ipset destroy hash_ip2
        sleep 0.05
done

In the race case the possible order of the operations are

	CPU0			CPU1
	ip_set_test
				ipset swap hash_ip1 hash_ip2
				ipset destroy hash_ip2
	hash_net_kadt

Swap replaces hash_ip1 with hash_ip2 and then destroy removes hash_ip2 which
is the original hash_ip1. ip_set_test was called on hash_ip1 and because destroy
removed it, hash_net_kadt crashes.

The fix is to force ip_set_swap() to wait for all readers to finish accessing the
old set pointers by calling synchronize_rcu().

The first version of the patch was written by Linkui Xiao <xiaolinkui@kylinos.cn>.

v2: synchronize_rcu() is moved into ip_set_swap() in order not to burden
    ip_set_destroy() unnecessarily when all sets are destroyed.
v3: Florian Westphal pointed out that all netfilter hooks run with rcu_read_lock() held
    and em_ipset.c wraps the entire ip_set_test() in rcu read lock/unlock pair.
    So there's no need to extend the rcu read locked area in ipset itself.

Closes: https://lore.kernel.org/all/69e7963b-e7f8-3ad0-210-7b86eebf7f78@netfilter.org/
Reported by: Linkui Xiao <xiaolinkui@kylinos.cn>
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13 18:18:10 +01:00
Zhengchao Shao
7ccf772a8b ipv4: igmp: fix refcnt uaf issue when receiving igmp query packet
[ 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:
	<TASK>
	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)
	</TASK>

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: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-08 08:44:27 +01:00
Kunwu Chan
fc23517c87 ipv4: Correct/silence an endian warning in __ip_do_redirect
[ 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: 969447f226 ("ipv4: use new_gw for redirect neigh lookup")
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Link: https://lore.kernel.org/r/20231119141759.420477-1-chentao@kylinos.cn
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-08 08:44:23 +01:00
Pablo Neira Ayuso
b053223b7c netfilter: nf_tables: bogus EBUSY when deleting flowtable after flush (for 5.4)
3f0465a9ef02 ("netfilter: nf_tables: dynamically allocate hooks per
net_device in flowtables") reworks flowtable support to allow for
dynamic allocation of hooks, which implicitly fixes the following
bogus EBUSY in transaction:

  delete flowtable
  add flowtable # same flowtable with same devices, it hits EBUSY

This patch does not exist in any tree, but it fixes this issue for
-stable Linux kernel 5.4

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:24 +00:00
Pablo Neira Ayuso
c35df8b8c5 netfilter: nf_tables: disable toggling dormant table state more than once
commit c9bd26513b3a11b3adb3c2ed8a31a01a87173ff1 upstream.

nft -f -<<EOF
add table ip t
add table ip t { flags dormant; }
add chain ip t c { type filter hook input priority 0; }
add table ip t
EOF

Triggers a splat from nf core on next table delete because we lose
track of right hook register state:

WARNING: CPU: 2 PID: 1597 at net/netfilter/core.c:501 __nf_unregister_net_hook
RIP: 0010:__nf_unregister_net_hook+0x41b/0x570
 nf_unregister_net_hook+0xb4/0xf0
 __nf_tables_unregister_hook+0x160/0x1d0
[..]

The above should have table in *active* state, but in fact no
hooks were registered.

Reject on/off/on games rather than attempting to fix this.

Fixes: 179d9ba5559a ("netfilter: nf_tables: fix table flag updates")
Reported-by: "Lee, Cherie-Anne" <cherie.lee@starlabs.sg>
Cc: Bing-Jhong Billy Jheng <billy@starlabs.sg>
Cc: info@starlabs.sg
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
e10f661adc netfilter: nf_tables: fix table flag updates
commit 179d9ba5559a756f4322583388b3213fe4e391b0 upstream.

The dormant flag need to be updated from the preparation phase,
otherwise, two consecutive requests to dorm a table in the same batch
might try to remove the same hooks twice, resulting in the following
warning:

 hook not found, pf 3 num 0
 WARNING: CPU: 0 PID: 334 at net/netfilter/core.c:480 __nf_unregister_net_hook+0x1eb/0x610 net/netfilter/core.c:480
 Modules linked in:
 CPU: 0 PID: 334 Comm: kworker/u4:5 Not tainted 5.12.0-syzkaller #0
 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 Workqueue: netns cleanup_net
 RIP: 0010:__nf_unregister_net_hook+0x1eb/0x610 net/netfilter/core.c:480

This patch is a partial revert of 0ce7cf4127f1 ("netfilter: nftables:
update table flags from the commit phase") to restore the previous
behaviour.

However, there is still another problem: A batch containing a series of
dorm-wakeup-dorm table and vice-versa also trigger the warning above
since hook unregistration happens from the preparation phase, while hook
registration occurs from the commit phase.

To fix this problem, this patch adds two internal flags to annotate the
original dormant flag status which are __NFT_TABLE_F_WAS_DORMANT and
__NFT_TABLE_F_WAS_AWAKEN, to restore it from the abort path.

The __NFT_TABLE_F_UPDATE bitmask allows to handle the dormant flag update
with one single transaction.

Reported-by: syzbot+7ad5cd1615f2d89c6e7e@syzkaller.appspotmail.com
Fixes: 0ce7cf4127f1 ("netfilter: nftables: update table flags from the commit phase")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
46c2947fcd netfilter: nftables: update table flags from the commit phase
commit 0ce7cf4127f14078ca598ba9700d813178a59409 upstream.

Do not update table flags from the preparation phase. Store the flags
update into the transaction, then update the flags from the commit
phase.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
b09e6ccf0d netfilter: nf_tables: double hook unregistration in netns path
commit f9a43007d3f7ba76d5e7f9421094f00f2ef202f8 upstream.

__nft_release_hooks() is called from pre_netns exit path which
unregisters the hooks, then the NETDEV_UNREGISTER event is triggered
which unregisters the hooks again.

[  565.221461] WARNING: CPU: 18 PID: 193 at net/netfilter/core.c:495 __nf_unregister_net_hook+0x247/0x270
[...]
[  565.246890] CPU: 18 PID: 193 Comm: kworker/u64:1 Tainted: G            E     5.18.0-rc7+ #27
[  565.253682] Workqueue: netns cleanup_net
[  565.257059] RIP: 0010:__nf_unregister_net_hook+0x247/0x270
[...]
[  565.297120] Call Trace:
[  565.300900]  <TASK>
[  565.304683]  nf_tables_flowtable_event+0x16a/0x220 [nf_tables]
[  565.308518]  raw_notifier_call_chain+0x63/0x80
[  565.312386]  unregister_netdevice_many+0x54f/0xb50

Unregister and destroy netdev hook from netns pre_exit via kfree_rcu
so the NETDEV_UNREGISTER path see unregistered hooks.

Fixes: 767d1216bff8 ("netfilter: nftables: fix possible UAF over chains from packet path in netns")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
b05a24cc45 netfilter: nf_tables: unregister flowtable hooks on netns exit
commit 6069da443bf65f513bb507bb21e2f87cfb1ad0b6 upstream.

Unregister flowtable hooks before they are releases via
nf_tables_flowtable_destroy() otherwise hook core reports UAF.

BUG: KASAN: use-after-free in nf_hook_entries_grow+0x5a7/0x700 net/netfilter/core.c:142 net/netfilter/core.c:142
Read of size 4 at addr ffff8880736f7438 by task syz-executor579/3666

CPU: 0 PID: 3666 Comm: syz-executor579 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 __dump_stack lib/dump_stack.c:88 [inline] lib/dump_stack.c:106
 dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 lib/dump_stack.c:106
 print_address_description+0x65/0x380 mm/kasan/report.c:247 mm/kasan/report.c:247
 __kasan_report mm/kasan/report.c:433 [inline]
 __kasan_report mm/kasan/report.c:433 [inline] mm/kasan/report.c:450
 kasan_report+0x19a/0x1f0 mm/kasan/report.c:450 mm/kasan/report.c:450
 nf_hook_entries_grow+0x5a7/0x700 net/netfilter/core.c:142 net/netfilter/core.c:142
 __nf_register_net_hook+0x27e/0x8d0 net/netfilter/core.c:429 net/netfilter/core.c:429
 nf_register_net_hook+0xaa/0x180 net/netfilter/core.c:571 net/netfilter/core.c:571
 nft_register_flowtable_net_hooks+0x3c5/0x730 net/netfilter/nf_tables_api.c:7232 net/netfilter/nf_tables_api.c:7232
 nf_tables_newflowtable+0x2022/0x2cf0 net/netfilter/nf_tables_api.c:7430 net/netfilter/nf_tables_api.c:7430
 nfnetlink_rcv_batch net/netfilter/nfnetlink.c:513 [inline]
 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline]
 nfnetlink_rcv_batch net/netfilter/nfnetlink.c:513 [inline] net/netfilter/nfnetlink.c:652
 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline] net/netfilter/nfnetlink.c:652
 nfnetlink_rcv+0x10e6/0x2550 net/netfilter/nfnetlink.c:652 net/netfilter/nfnetlink.c:652

__nft_release_hook() calls nft_unregister_flowtable_net_hooks() which
only unregisters the hooks, then after RCU grace period, it is
guaranteed that no packets add new entries to the flowtable (no flow
offload rules and flowtable hooks are reachable from packet path), so it
is safe to call nf_flow_table_free() which cleans up the remaining
entries from the flowtable (both software and hardware) and it unbinds
the flow_block.

Fixes: ff4bf2f42a40 ("netfilter: nf_tables: add nft_unregister_flowtable_hook()")
Reported-by: syzbot+e918523f77e62790d6d9@syzkaller.appspotmail.com
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
a995a68e8a netfilter: nf_tables: fix memleak when more than 255 elements expired
commit cf5000a7787cbc10341091d37245a42c119d26c5 upstream.

When more than 255 elements expired we're supposed to switch to a new gc
container structure.

This never happens: u8 type will wrap before reaching the boundary
and nft_trans_gc_space() always returns true.

This means we recycle the initial gc container structure and
lose track of the elements that came before.

While at it, don't deref 'gc' after we've passed it to call_rcu.

Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Reported-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
b95d7af657 netfilter: nft_set_hash: try later when GC hits EAGAIN on iteration
commit b079155faae94e9b3ab9337e82100a914ebb4e8d upstream.

Skip GC run if iterator rewinds to the beginning with EAGAIN, otherwise GC
might collect the same element more than once.

Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
61a7b3de20 netfilter: nft_set_rbtree: use read spinlock to avoid datapath contention
commit 96b33300fba880ec0eafcf3d82486f3463b4b6da upstream.

rbtree GC does not modify the datastructure, instead it collects expired
elements and it enqueues a GC transaction. Use a read spinlock instead
to avoid data contention while GC worker is running.

Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
03caf75da1 netfilter: nft_set_rbtree: skip sync GC for new elements in this transaction
commit 2ee52ae94baabf7ee09cf2a8d854b990dac5d0e4 upstream.

New elements in this transaction might expired before such transaction
ends. Skip sync GC for such elements otherwise commit path might walk
over an already released object. Once transaction is finished, async GC
will collect such expired element.

Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Florian Westphal
021d734c7e netfilter: nf_tables: defer gc run if previous batch is still pending
commit 8e51830e29e12670b4c10df070a4ea4c9593e961 upstream.

Don't queue more gc work, else we may queue the same elements multiple
times.

If an element is flagged as dead, this can mean that either the previous
gc request was invalidated/discarded by a transaction or that the previous
request is still pending in the system work queue.

The latter will happen if the gc interval is set to a very low value,
e.g. 1ms, and system work queue is backlogged.

The sets refcount is 1 if no previous gc requeusts are queued, so add
a helper for this and skip gc run if old requests are pending.

Add a helper for this and skip the gc run in this case.

Fixes: f6c383b8c31a ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
38ed6a5f83 netfilter: nf_tables: use correct lock to protect gc_list
commit 8357bc946a2abc2a10ca40e5a2105d2b4c57515e upstream.

Use nf_tables_gc_list_lock spinlock, not nf_tables_destroy_list_lock to
protect the gc_list.

Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
4b6346dc1e netfilter: nf_tables: GC transaction race with abort path
commit 720344340fb9be2765bbaab7b292ece0a4570eae upstream.

Abort path is missing a synchronization point with GC transactions. Add
GC sequence number hence any GC transaction losing race will be
discarded.

Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
b76dcf4662 netfilter: nf_tables: GC transaction race with netns dismantle
commit 02c6c24402bf1c1e986899c14ba22a10b510916b upstream.

Use maybe_get_net() since GC workqueue might race with netns exit path.

Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
29ff9b8efb netfilter: nf_tables: fix GC transaction races with netns and netlink event exit path
commit 6a33d8b73dfac0a41f3877894b38082bd0c9a5bc upstream.

Netlink event path is missing a synchronization point with GC
transactions. Add GC sequence number update to netns release path and
netlink event path, any GC transaction losing race will be discarded.

Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:23 +00:00
Pablo Neira Ayuso
1398a0eee2 netfilter: nf_tables: remove busy mark and gc batch API
commit a2dd0233cbc4d8a0abb5f64487487ffc9265beb5 upstream.

Ditch it, it has been replace it by the GC transaction API and it has no
clients anymore.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:22 +00:00
Pablo Neira Ayuso
85520a1f1d netfilter: nft_set_hash: mark set element as dead when deleting from packet path
commit c92db3030492b8ad1d0faace7a93bbcf53850d0c upstream.

Set on the NFT_SET_ELEM_DEAD_BIT flag on this element, instead of
performing element removal which might race with an ongoing transaction.
Enable gc when dynamic flag is set on since dynset deletion requires
garbage collection after this patch.

Fixes: d0a8d877da ("netfilter: nft_dynset: support for element deletion")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:22 +00:00
Pablo Neira Ayuso
c357648929 netfilter: nf_tables: adapt set backend to use GC transaction API
commit f6c383b8c31a93752a52697f8430a71dcbc46adf upstream.

Use the GC transaction API to replace the old and buggy gc API and the
busy mark approach.

No set elements are removed from async garbage collection anymore,
instead the _DEAD bit is set on so the set element is not visible from
lookup path anymore. Async GC enqueues transaction work that might be
aborted and retried later.

rbtree and pipapo set backends does not set on the _DEAD bit from the
sync GC path since this runs in control plane path where mutex is held.
In this case, set elements are deactivated, removed and then released
via RCU callback, sync GC never fails.

Fixes: 3c4287f62044 ("nf_tables: Add set type for arbitrary concatenation of ranges")
Fixes: 8d8540c4f5 ("netfilter: nft_set_rbtree: add timeout support")
Fixes: 9d0982927e ("netfilter: nft_hash: add support for timeouts")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:22 +00:00
Pablo Neira Ayuso
bbdb3b65aa netfilter: nf_tables: GC transaction API to avoid race with control plane
commit 5f68718b34a531a556f2f50300ead2862278da26 upstream.

The set types rhashtable and rbtree use a GC worker to reclaim memory.
>From system work queue, in periodic intervals, a scan of the table is
done.

The major caveat here is that the nft transaction mutex is not held.
This causes a race between control plane and GC when they attempt to
delete the same element.

We cannot grab the netlink mutex from the work queue, because the
control plane has to wait for the GC work queue in case the set is to be
removed, so we get following deadlock:

   cpu 1                                cpu2
     GC work                            transaction comes in , lock nft mutex
       `acquire nft mutex // BLOCKS
                                        transaction asks to remove the set
                                        set destruction calls cancel_work_sync()

cancel_work_sync will now block forever, because it is waiting for the
mutex the caller already owns.

This patch adds a new API that deals with garbage collection in two
steps:

1) Lockless GC of expired elements sets on the NFT_SET_ELEM_DEAD_BIT
   so they are not visible via lookup. Annotate current GC sequence in
   the GC transaction. Enqueue GC transaction work as soon as it is
   full. If ruleset is updated, then GC transaction is aborted and
   retried later.

2) GC work grabs the mutex. If GC sequence has changed then this GC
   transaction lost race with control plane, abort it as it contains
   stale references to objects and let GC try again later. If the
   ruleset is intact, then this GC transaction deactivates and removes
   the elements and it uses call_rcu() to destroy elements.

Note that no elements are removed from GC lockless path, the _DEAD bit
is set and pointers are collected. GC catchall does not remove the
elements anymore too. There is a new set->dead flag that is set on to
abort the GC transaction to deal with set->ops->destroy() path which
removes the remaining elements in the set from commit_release, where no
mutex is held.

To deal with GC when mutex is held, which allows safe deactivate and
removal, add sync GC API which releases the set element object via
call_rcu(). This is used by rbtree and pipapo backends which also
perform garbage collection from control plane path.

Since element removal from sets can happen from control plane and
element garbage collection/timeout, it is necessary to keep the set
structure alive until all elements have been deactivated and destroyed.

We cannot do a cancel_work_sync or flush_work in nft_set_destroy because
its called with the transaction mutex held, but the aforementioned async
work queue might be blocked on the very mutex that nft_set_destroy()
callchain is sitting on.

This gives us the choice of ABBA deadlock or UaF.

To avoid both, add set->refs refcount_t member. The GC API can then
increment the set refcount and release it once the elements have been
free'd.

Set backends are adapted to use the GC transaction API in a follow up
patch entitled:

  ("netfilter: nf_tables: use gc transaction API in set backends")

This is joint work with Florian Westphal.

Fixes: cfed7e1b1f ("netfilter: nf_tables: add set garbage collection helpers")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:22 +00:00
Florian Westphal
1da4874d05 netfilter: nf_tables: don't skip expired elements during walk
commit 24138933b97b055d486e8064b4a1721702442a9b upstream.

There is an asymmetry between commit/abort and preparation phase if the
following conditions are met:

1. set is a verdict map ("1.2.3.4 : jump foo")
2. timeouts are enabled

In this case, following sequence is problematic:

1. element E in set S refers to chain C
2. userspace requests removal of set S
3. kernel does a set walk to decrement chain->use count for all elements
   from preparation phase
4. kernel does another set walk to remove elements from the commit phase
   (or another walk to do a chain->use increment for all elements from
    abort phase)

If E has already expired in 1), it will be ignored during list walk, so its use count
won't have been changed.

Then, when set is culled, ->destroy callback will zap the element via
nf_tables_set_elem_destroy(), but this function is only safe for
elements that have been deactivated earlier from the preparation phase:
lack of earlier deactivate removes the element but leaks the chain use
count, which results in a WARN splat when the chain gets removed later,
plus a leak of the nft_chain structure.

Update pipapo_get() not to skip expired elements, otherwise flush
command reports bogus ENOENT errors.

Fixes: 3c4287f62044 ("nf_tables: Add set type for arbitrary concatenation of ranges")
Fixes: 8d8540c4f5 ("netfilter: nft_set_rbtree: add timeout support")
Fixes: 9d0982927e ("netfilter: nft_hash: add support for timeouts")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:22 +00:00
Florian Westphal
acaee227cf netfilter: nft_set_rbtree: fix overlap expiration walk
commit f718863aca469a109895cb855e6b81fff4827d71 upstream.

The lazy gc on insert that should remove timed-out entries fails to release
the other half of the interval, if any.

Can be reproduced with tests/shell/testcases/sets/0044interval_overlap_0
in nftables.git and kmemleak enabled kernel.

Second bug is the use of rbe_prev vs. prev pointer.
If rbe_prev() returns NULL after at least one iteration, rbe_prev points
to element that is not an end interval, hence it should not be removed.

Lastly, check the genmask of the end interval if this is active in the
current generation.

Fixes: c9e6978e2725 ("netfilter: nft_set_rbtree: Switch to node list walk for overlap detection")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:22 +00:00
Florian Westphal
899aa56385 netfilter: nft_set_rbtree: fix null deref on element insertion
commit 61ae320a29b0540c16931816299eb86bf2b66c08 upstream.

There is no guarantee that rb_prev() will not return NULL in nft_rbtree_gc_elem():

general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
 nft_add_set_elem+0x14b0/0x2990
  nf_tables_newsetelem+0x528/0xb30

Furthermore, there is a possible use-after-free while iterating,
'node' can be free'd so we need to cache the next value to use.

Fixes: c9e6978e2725 ("netfilter: nft_set_rbtree: Switch to node list walk for overlap detection")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:22 +00:00
Pablo Neira Ayuso
181859bdfb netfilter: nft_set_rbtree: Switch to node list walk for overlap detection
commit c9e6978e2725a7d4b6cd23b2facd3f11422c0643 upstream.

...instead of a tree descent, which became overly complicated in an
attempt to cover cases where expired or inactive elements would affect
comparisons with the new element being inserted.

Further, it turned out that it's probably impossible to cover all those
cases, as inactive nodes might entirely hide subtrees consisting of a
complete interval plus a node that makes the current insertion not
overlap.

To speed up the overlap check, descent the tree to find a greater
element that is closer to the key value to insert. Then walk down the
node list for overlap detection. Starting the overlap check from
rb_first() unconditionally is slow, it takes 10 times longer due to the
full linear traversal of the list.

Moreover, perform garbage collection of expired elements when walking
down the node list to avoid bogus overlap reports.

For the insertion operation itself, this essentially reverts back to the
implementation before commit 7c84d41416d8 ("netfilter: nft_set_rbtree:
Detect partial overlaps on insertion"), except that cases of complete
overlap are already handled in the overlap detection phase itself, which
slightly simplifies the loop to find the insertion point.

Based on initial patch from Stefano Brivio, including text from the
original patch description too.

Fixes: 7c84d41416d8 ("netfilter: nft_set_rbtree: Detect partial overlaps on insertion")
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:22 +00:00
Pablo Neira Ayuso
3c7ec098e3 netfilter: nf_tables: drop map element references from preparation phase
commit 628bd3e49cba1c066228e23d71a852c23e26da73 upstream.

set .destroy callback releases the references to other objects in maps.
This is very late and it results in spurious EBUSY errors. Drop refcount
from the preparation phase instead, update set backend not to drop
reference counter from set .destroy path.

Exceptions: NFT_TRANS_PREPARE_ERROR does not require to drop the
reference counter because the transaction abort path releases the map
references for each element since the set is unbound. The abort path
also deals with releasing reference counter for new elements added to
unbound sets.

Fixes: 591054469b ("netfilter: nf_tables: revisit chain/object refcounting from elements")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:22 +00:00
Pablo Neira Ayuso
6b880f3b2c netfilter: nftables: rename set element data activation/deactivation functions
commit f8bb7889af58d8e74d2d61c76b1418230f1610fa upstream.

Rename:

- nft_set_elem_activate() to nft_set_elem_data_activate().
- nft_set_elem_deactivate() to nft_set_elem_data_deactivate().

To prepare for updates in the set element infrastructure to add support
for the special catch-all element.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:22 +00:00
Pablo Neira Ayuso
e1eed9e0b5 netfilter: nf_tables: pass context to nft_set_destroy()
commit 0c2a85edd143162b3a698f31e94bf8cdc041da87 upstream.

The patch that adds support for stateful expressions in set definitions
require this.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:22 +00:00
Johnathan Mantey
229738d717 Revert ncsi: Propagate carrier gain/loss events to the NCSI controller
commit 9e2e7efbbbff69d8340abb56d375dd79d1f5770f upstream.

This reverts commit 3780bb29311eccb7a1c9641032a112eed237f7e3.

The cited commit introduced unwanted behavior.

The intent for the commit was to be able to detect carrier loss/gain
for just the NIC connected to the BMC. The unwanted effect is a
carrier loss for auxiliary paths also causes the BMC to lose
carrier. The BMC never regains carrier despite the secondary NIC
regaining a link.

This change, when merged, needs to be backported to stable kernels.
5.4-stable, 5.10-stable, 5.15-stable, 6.1-stable, 6.5-stable

Fixes: 3780bb29311e ("ncsi: Propagate carrier gain/loss events to the NCSI controller")
CC: stable@vger.kernel.org
Signed-off-by: Johnathan Mantey <johnathanx.mantey@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:50:21 +00:00
Linkui Xiao
b2762d13df netfilter: nf_conntrack_bridge: initialize err to 0
[ Upstream commit a44af08e3d4d7566eeea98d7a29fe06e7b9de944 ]

K2CI reported a problem:

	consume_skb(skb);
	return err;
[nf_br_ip_fragment() error]  uninitialized symbol 'err'.

err is not initialized, because returning 0 is expected, initialize err
to 0.

Fixes: 3c171f496e ("netfilter: bridge: add connection tracking system")
Reported-by: k2ci <kernel-bot@kylinos.cn>
Signed-off-by: Linkui Xiao <xiaolinkui@kylinos.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 16:50:17 +00:00
Shigeru Yoshida
f3b250d919 tipc: Fix kernel-infoleak due to uninitialized TLV value
[ Upstream commit fb317eb23b5ee4c37b0656a9a52a3db58d9dd072 ]

KMSAN reported the following kernel-infoleak issue:

=====================================================
BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in copy_to_user_iter lib/iov_iter.c:24 [inline]
BUG: KMSAN: kernel-infoleak in iterate_ubuf include/linux/iov_iter.h:29 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance include/linux/iov_iter.h:271 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x4ec/0x2bc0 lib/iov_iter.c:186
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_ubuf include/linux/iov_iter.h:29 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0x4ec/0x2bc0 lib/iov_iter.c:186
 copy_to_iter include/linux/uio.h:197 [inline]
 simple_copy_to_iter net/core/datagram.c:532 [inline]
 __skb_datagram_iter.5+0x148/0xe30 net/core/datagram.c:420
 skb_copy_datagram_iter+0x52/0x210 net/core/datagram.c:546
 skb_copy_datagram_msg include/linux/skbuff.h:3960 [inline]
 netlink_recvmsg+0x43d/0x1630 net/netlink/af_netlink.c:1967
 sock_recvmsg_nosec net/socket.c:1044 [inline]
 sock_recvmsg net/socket.c:1066 [inline]
 __sys_recvfrom+0x476/0x860 net/socket.c:2246
 __do_sys_recvfrom net/socket.c:2264 [inline]
 __se_sys_recvfrom net/socket.c:2260 [inline]
 __x64_sys_recvfrom+0x130/0x200 net/socket.c:2260
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 slab_post_alloc_hook+0x103/0x9e0 mm/slab.h:768
 slab_alloc_node mm/slub.c:3478 [inline]
 kmem_cache_alloc_node+0x5f7/0xb50 mm/slub.c:3523
 kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:560
 __alloc_skb+0x2fd/0x770 net/core/skbuff.c:651
 alloc_skb include/linux/skbuff.h:1286 [inline]
 tipc_tlv_alloc net/tipc/netlink_compat.c:156 [inline]
 tipc_get_err_tlv+0x90/0x5d0 net/tipc/netlink_compat.c:170
 tipc_nl_compat_recv+0x1042/0x15d0 net/tipc/netlink_compat.c:1324
 genl_family_rcv_msg_doit net/netlink/genetlink.c:972 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:1052 [inline]
 genl_rcv_msg+0x1220/0x12c0 net/netlink/genetlink.c:1067
 netlink_rcv_skb+0x4a4/0x6a0 net/netlink/af_netlink.c:2545
 genl_rcv+0x41/0x60 net/netlink/genetlink.c:1076
 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
 netlink_unicast+0xf4b/0x1230 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x1242/0x1420 net/netlink/af_netlink.c:1910
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x997/0xd60 net/socket.c:2588
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2642
 __sys_sendmsg net/socket.c:2671 [inline]
 __do_sys_sendmsg net/socket.c:2680 [inline]
 __se_sys_sendmsg net/socket.c:2678 [inline]
 __x64_sys_sendmsg+0x2fa/0x4a0 net/socket.c:2678
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Bytes 34-35 of 36 are uninitialized
Memory access of size 36 starts at ffff88802d464a00
Data copied to user address 00007ff55033c0a0

CPU: 0 PID: 30322 Comm: syz-executor.0 Not tainted 6.6.0-14500-g1c41041124bd #10
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-1.fc38 04/01/2014
=====================================================

tipc_add_tlv() puts TLV descriptor and value onto `skb`. This size is
calculated with TLV_SPACE() macro. It adds the size of struct tlv_desc and
the length of TLV value passed as an argument, and aligns the result to a
multiple of TLV_ALIGNTO, i.e., a multiple of 4 bytes.

If the size of struct tlv_desc plus the length of TLV value is not aligned,
the current implementation leaves the remaining bytes uninitialized. This
is the cause of the above kernel-infoleak issue.

This patch resolves this issue by clearing data up to an aligned size.

Fixes: d0796d1ef6 ("tipc: convert legacy nl bearer dump to nl compat")
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 16:50:16 +00:00
ZhengHan Wang
3c4236f1b2 Bluetooth: Fix double free in hci_conn_cleanup
[ Upstream commit a85fb91e3d728bdfc80833167e8162cce8bc7004 ]

syzbot reports a slab use-after-free in hci_conn_hash_flush [1].
After releasing an object using hci_conn_del_sysfs in the
hci_conn_cleanup function, releasing the same object again
using the hci_dev_put and hci_conn_put functions causes a double free.
Here's a simplified flow:

hci_conn_del_sysfs:
  hci_dev_put
    put_device
      kobject_put
        kref_put
          kobject_release
            kobject_cleanup
              kfree_const
                kfree(name)

hci_dev_put:
  ...
    kfree(name)

hci_conn_put:
  put_device
    ...
      kfree(name)

This patch drop the hci_dev_put and hci_conn_put function
call in hci_conn_cleanup function, because the object is
freed in hci_conn_del_sysfs function.

This patch also fixes the refcounting in hci_conn_add_sysfs() and
hci_conn_del_sysfs() to take into account device_add() failures.

This fixes CVE-2023-28464.

Link: https://syzkaller.appspot.com/bug?id=1bb51491ca5df96a5f724899d1dbb87afda61419 [1]

Signed-off-by: ZhengHan Wang <wzhmmmmm@gmail.com>
Co-developed-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 16:50:14 +00:00
Eric Dumazet
252bde6b17 net: annotate data-races around sk->sk_dst_pending_confirm
[ 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 <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 16:50:14 +00:00
Ping-Ke Shih
efeae5f497 wifi: mac80211: don't return unset power in ieee80211_get_tx_power()
[ Upstream commit e160ab85166e77347d0cbe5149045cb25e83937f ]

We can get a UBSAN warning if ieee80211_get_tx_power() returns the
INT_MIN value mac80211 internally uses for "unset power level".

 UBSAN: signed-integer-overflow in net/wireless/nl80211.c:3816:5
 -2147483648 * 100 cannot be represented in type 'int'
 CPU: 0 PID: 20433 Comm: insmod Tainted: G        WC OE
 Call Trace:
  dump_stack+0x74/0x92
  ubsan_epilogue+0x9/0x50
  handle_overflow+0x8d/0xd0
  __ubsan_handle_mul_overflow+0xe/0x10
  nl80211_send_iface+0x688/0x6b0 [cfg80211]
  [...]
  cfg80211_register_wdev+0x78/0xb0 [cfg80211]
  cfg80211_netdev_notifier_call+0x200/0x620 [cfg80211]
  [...]
  ieee80211_if_add+0x60e/0x8f0 [mac80211]
  ieee80211_register_hw+0xda5/0x1170 [mac80211]

In this case, simply return an error instead, to indicate
that no data is available.

Cc: Zong-Zhe Yang <kevin_yang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://lore.kernel.org/r/20230203023636.4418-1-pkshih@realtek.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 16:50:13 +00:00
Florian Westphal
21858a75dc netfilter: nat: fix ipv6 nat redirect with mapped and scoped addresses
[ Upstream commit 80abbe8a8263106fe45a4f293b92b5c74cc9cc8a ]

The ipv6 redirect target was derived from the ipv4 one, i.e. its
identical to a 'dnat' with the first (primary) address assigned to the
network interface.  The code has been moved around to make it usable
from nf_tables too, but its still the same as it was back when this
was added in 2012.

IPv6, however, has different types of addresses, if the 'wrong' address
comes first the redirection does not work.

In Daniels case, the addresses are:
  inet6 ::ffff:192 ...
  inet6 2a01: ...

... so the function attempts to redirect to the mapped address.

Add more checks before the address is deemed correct:
1. If the packets' daddr is scoped, search for a scoped address too
2. skip tentative addresses
3. skip mapped addresses

Use the first address that appears to match our needs.

Reported-by: Daniel Huhardeaux <tech@tootai.net>
Closes: https://lore.kernel.org/netfilter/71be06b8-6aa0-4cf9-9e0b-e2839b01b22f@tootai.net/
Fixes: 115e23ac78 ("netfilter: ip6tables: add REDIRECT target")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 10:30:16 +01:00
Jeremy Sowden
ae99c5e16a netfilter: nft_redir: use struct nf_nat_range2 throughout and deduplicate eval call-backs
[ Upstream commit 6f56ad1b92328997e1b1792047099df6f8d7acb5 ]

`nf_nat_redirect_ipv4` takes a `struct nf_nat_ipv4_multi_range_compat`,
but converts it internally to a `struct nf_nat_range2`.  Change the
function to take the latter, factor out the code now shared with
`nf_nat_redirect_ipv6`, move the conversion to the xt_REDIRECT module,
and update the ipv4 range initialization in the nft_redir module.

Replace a bare hex constant for 127.0.0.1 with a macro.

Remove `WARN_ON`.  `nf_nat_setup_info` calls `nf_ct_is_confirmed`:

	/* Can't setup nat info for confirmed ct. */
	if (nf_ct_is_confirmed(ct))
		return NF_ACCEPT;

This means that `ct` cannot be null or the kernel will crash, and
implies that `ctinfo` is `IP_CT_NEW` or `IP_CT_RELATED`.

nft_redir has separate ipv4 and ipv6 call-backs which share much of
their code, and an inet one switch containing a switch that calls one of
the others based on the family of the packet.  Merge the ipv4 and ipv6
ones into the inet one in order to get rid of the duplicate code.

Const-qualify the `priv` pointer since we don't need to write through
it.

Assign `priv->flags` to the range instead of OR-ing it in.

Set the `NF_NAT_RANGE_PROTO_SPECIFIED` flag once during init, rather
than on every eval.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Stable-dep-of: 80abbe8a8263 ("netfilter: nat: fix ipv6 nat redirect with mapped and scoped addresses")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 10:30:16 +01:00
Maciej Żenczykowski
11380557c2 netfilter: xt_recent: fix (increase) ipv6 literal buffer length
[ Upstream commit 7b308feb4fd2d1c06919445c65c8fbf8e9fd1781 ]

in6_pton() supports 'low-32-bit dot-decimal representation'
(this is useful with DNS64/NAT64 networks for example):

  # echo +aaaa:bbbb:cccc:dddd:eeee:ffff:1.2.3.4 > /proc/self/net/xt_recent/DEFAULT
  # cat /proc/self/net/xt_recent/DEFAULT
  src=aaaa:bbbb:cccc:dddd:eeee:ffff:0102:0304 ttl: 0 last_seen: 9733848829 oldest_pkt: 1 9733848829

but the provided buffer is too short:

  # echo +aaaa:bbbb:cccc:dddd:eeee:ffff:255.255.255.255 > /proc/self/net/xt_recent/DEFAULT
  -bash: echo: write error: Invalid argument

Fixes: 079aa88fe7 ("netfilter: xt_recent: IPv6 support")
Signed-off-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 10:30:16 +01:00
D. Wythe
f8065cde49 net/smc: fix dangling sock under state SMC_APPFINCLOSEWAIT
[ Upstream commit 5211c9729484c923f8d2e06bd29f9322cc42bb8f ]

Considering scenario:

				smc_cdc_rx_handler
__smc_release
				sock_set_flag
smc_close_active()
sock_set_flag

__set_bit(DEAD)			__set_bit(DONE)

Dues to __set_bit is not atomic, the DEAD or DONE might be lost.
if the DEAD flag lost, the state SMC_CLOSED  will be never be reached
in smc_close_passive_work:

if (sock_flag(sk, SOCK_DEAD) &&
	smc_close_sent_any_close(conn)) {
	sk->sk_state = SMC_CLOSED;
} else {
	/* just shutdown, but not yet closed locally */
	sk->sk_state = SMC_APPFINCLOSEWAIT;
}

Replace sock_set_flags or __set_bit to set_bit will fix this problem.
Since set_bit is atomic.

Fixes: b38d732477 ("smc: socket closing and linkgroup cleanup")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 10:30:16 +01:00
Kuniyuki Iwashima
e5a664ef49 dccp/tcp: Call security_inet_conn_request() after setting IPv6 addresses.
[ Upstream commit 23be1e0e2a83a8543214d2599a31d9a2185a796b ]

Initially, commit 4237c75c0a ("[MLSXFRM]: Auto-labeling of child
sockets") introduced security_inet_conn_request() in some functions
where reqsk is allocated.  The hook is added just after the allocation,
so reqsk's IPv6 remote address was not initialised then.

However, SELinux/Smack started to read it in netlbl_req_setattr()
after commit e1adea9270 ("calipso: Allow request sockets to be
relabelled by the lsm.").

Commit 284904aa79 ("lsm: Relocate the IPv4 security_inet_conn_request()
hooks") fixed that kind of issue only in TCPv4 because IPv6 labeling was
not supported at that time.  Finally, the same issue was introduced again
in IPv6.

Let's apply the same fix on DCCPv6 and TCPv6.

Fixes: e1adea9270 ("calipso: Allow request sockets to be relabelled by the lsm.")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 10:30:15 +01:00
Kuniyuki Iwashima
3af0af2f98 dccp: Call security_inet_conn_request() after setting IPv4 addresses.
[ Upstream commit fa2df45af13091f76b89adb84a28f13818d5d631 ]

Initially, commit 4237c75c0a ("[MLSXFRM]: Auto-labeling of child
sockets") introduced security_inet_conn_request() in some functions
where reqsk is allocated.  The hook is added just after the allocation,
so reqsk's IPv4 remote address was not initialised then.

However, SELinux/Smack started to read it in netlbl_req_setattr()
after the cited commits.

This bug was partially fixed by commit 284904aa79 ("lsm: Relocate
the IPv4 security_inet_conn_request() hooks").

This patch fixes the last bug in DCCPv4.

Fixes: 389fb800ac ("netlabel: Label incoming TCP connections correctly in SELinux")
Fixes: 07feee8f81 ("netlabel: Cleanup the Smack/NetLabel code to fix incoming TCP connections")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 10:30:15 +01:00
Shigeru Yoshida
2199260c42 tipc: Change nla_policy for bearer-related names to NLA_NUL_STRING
[ Upstream commit 19b3f72a41a8751e26bffc093bb7e1cef29ad579 ]

syzbot reported the following uninit-value access issue [1]:

=====================================================
BUG: KMSAN: uninit-value in strlen lib/string.c:418 [inline]
BUG: KMSAN: uninit-value in strstr+0xb8/0x2f0 lib/string.c:756
 strlen lib/string.c:418 [inline]
 strstr+0xb8/0x2f0 lib/string.c:756
 tipc_nl_node_reset_link_stats+0x3ea/0xb50 net/tipc/node.c:2595
 genl_family_rcv_msg_doit net/netlink/genetlink.c:971 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:1051 [inline]
 genl_rcv_msg+0x11ec/0x1290 net/netlink/genetlink.c:1066
 netlink_rcv_skb+0x371/0x650 net/netlink/af_netlink.c:2545
 genl_rcv+0x40/0x60 net/netlink/genetlink.c:1075
 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
 netlink_unicast+0xf47/0x1250 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x1238/0x13d0 net/netlink/af_netlink.c:1910
 sock_sendmsg_nosec net/socket.c:730 [inline]
 sock_sendmsg net/socket.c:753 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2541
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2595
 __sys_sendmsg net/socket.c:2624 [inline]
 __do_sys_sendmsg net/socket.c:2633 [inline]
 __se_sys_sendmsg net/socket.c:2631 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2631
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 slab_post_alloc_hook+0x12f/0xb70 mm/slab.h:767
 slab_alloc_node mm/slub.c:3478 [inline]
 kmem_cache_alloc_node+0x577/0xa80 mm/slub.c:3523
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:559
 __alloc_skb+0x318/0x740 net/core/skbuff.c:650
 alloc_skb include/linux/skbuff.h:1286 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1214 [inline]
 netlink_sendmsg+0xb34/0x13d0 net/netlink/af_netlink.c:1885
 sock_sendmsg_nosec net/socket.c:730 [inline]
 sock_sendmsg net/socket.c:753 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2541
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2595
 __sys_sendmsg net/socket.c:2624 [inline]
 __do_sys_sendmsg net/socket.c:2633 [inline]
 __se_sys_sendmsg net/socket.c:2631 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2631
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

TIPC bearer-related names including link names must be null-terminated
strings. If a link name which is not null-terminated is passed through
netlink, strstr() and similar functions can cause buffer overrun. This
causes the above issue.

This patch changes the nla_policy for bearer-related names from NLA_STRING
to NLA_NUL_STRING. This resolves the issue by ensuring that only
null-terminated strings are accepted as bearer-related names.

syzbot reported similar uninit-value issue related to bearer names [2]. The
root cause of this issue is that a non-null-terminated bearer name was
passed. This patch also resolved this issue.

Fixes: 7be57fc691 ("tipc: add link get/dump to new netlink api")
Fixes: 0655f6a863 ("tipc: add bearer disable/enable to new netlink api")
Reported-and-tested-by: syzbot+5138ca807af9d2b42574@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=5138ca807af9d2b42574 [1]
Reported-and-tested-by: syzbot+9425c47dccbcb4c17d51@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=9425c47dccbcb4c17d51 [2]
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231030075540.3784537-1-syoshida@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 10:30:15 +01:00
Willem de Bruijn
cbdcdf42d1 llc: verify mac len before reading mac header
[ Upstream commit 7b3ba18703a63f6fd487183b9262b08e5632da1b ]

LLC reads the mac header with eth_hdr without verifying that the skb
has an Ethernet header.

Syzbot was able to enter llc_rcv on a tun device. Tun can insert
packets without mac len and with user configurable skb->protocol
(passing a tun_pi header when not configuring IFF_NO_PI).

    BUG: KMSAN: uninit-value in llc_station_ac_send_test_r net/llc/llc_station.c:81 [inline]
    BUG: KMSAN: uninit-value in llc_station_rcv+0x6fb/0x1290 net/llc/llc_station.c:111
    llc_station_ac_send_test_r net/llc/llc_station.c:81 [inline]
    llc_station_rcv+0x6fb/0x1290 net/llc/llc_station.c:111
    llc_rcv+0xc5d/0x14a0 net/llc/llc_input.c:218
    __netif_receive_skb_one_core net/core/dev.c:5523 [inline]
    __netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5637
    netif_receive_skb_internal net/core/dev.c:5723 [inline]
    netif_receive_skb+0x58/0x660 net/core/dev.c:5782
    tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1555
    tun_get_user+0x54c5/0x69c0 drivers/net/tun.c:2002

Add a mac_len test before all three eth_hdr(skb) calls under net/llc.

There are further uses in include/net/llc_pdu.h. All these are
protected by a test skb->protocol == ETH_P_802_2. Which does not
protect against this tun scenario.

But the mac_len test added in this patch in llc_fixup_skb will
indirectly protect those too. That is called from llc_rcv before any
other LLC code.

It is tempting to just add a blanket mac_len check in llc_rcv, but
not sure whether that could break valid LLC paths that do not assume
an Ethernet header. 802.2 LLC may be used on top of non-802.3
protocols in principle. The below referenced commit shows that used
to, on top of Token Ring.

At least one of the three eth_hdr uses goes back to before the start
of git history. But the one that syzbot exercises is introduced in
this commit. That commit is old enough (2008), that effectively all
stable kernels should receive this.

Fixes: f83f1768f8 ("[LLC]: skb allocation size for responses")
Reported-by: syzbot+a8c7be6dee0de1b669cc@syzkaller.appspotmail.com
Signed-off-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20231025234251.3796495-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 10:30:15 +01:00
Yan Zhai
4482b250c8 ipv6: avoid atomic fragment on GSO packets
[ Upstream commit 03d6c848bfb406e9ef6d9846d759e97beaeea113 ]

When the ipv6 stack output a GSO packet, if its gso_size is larger than
dst MTU, then all segments would be fragmented. However, it is possible
for a GSO packet to have a trailing segment with smaller actual size
than both gso_size as well as the MTU, which leads to an "atomic
fragment". Atomic fragments are considered harmful in RFC-8021. An
Existing report from APNIC also shows that atomic fragments are more
likely to be dropped even it is equivalent to a no-op [1].

Add an extra check in the GSO slow output path. For each segment from
the original over-sized packet, if it fits with the path MTU, then avoid
generating an atomic fragment.

Link: https://www.potaroo.net/presentations/2022-03-01-ipv6-frag.pdf [1]
Fixes: b210de4f8c97 ("net: ipv6: Validate GSO SKB before finish IPv6 processing")
Reported-by: David Wragg <dwragg@cloudflare.com>
Signed-off-by: Yan Zhai <yan@cloudflare.com>
Link: https://lore.kernel.org/r/90912e3503a242dca0bc36958b11ed03a2696e5e.1698156966.git.yan@cloudflare.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 10:30:10 +01:00
Eric Dumazet
5105d46146 tcp: fix cookie_init_timestamp() overflows
[ 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: 9a568de481 ("tcp: switch TCP TS option (RFC 7323) to 1ms clock")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 10:30:10 +01:00