Subject: CVE-2023-52796: ipvlan: add ipvlan_route_v6_outbound() helper

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

ipvlan: add ipvlan_route_v6_outbound() helper

Inspired by syzbot reports using a stack of multiple ipvlan devices.

Reduce stack size needed in ipvlan_process_v6_outbound() by moving
the flowi6 struct used for the route lookup in an non inlined
helper. ipvlan_route_v6_outbound() needs 120 bytes on the stack,
immediately reclaimed.

Also make sure ipvlan_process_v4_outbound() is not inlined.

We might also have to lower MAX_NEST_DEV, because only syzbot uses
setups with more than four stacked devices.

BUG: TASK stack guard page was hit at ffffc9000e803ff8 (stack is ffffc9000e804000..ffffc9000e808000)
stack guard page: 0000 [#1] SMP KASAN
CPU: 0 PID: 13442 Comm: syz-executor.4 Not tainted 6.1.52-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
RIP: 0010:kasan_check_range+0x4/0x2a0 mm/kasan/generic.c:188
Code: 48 01 c6 48 89 c7 e8 db 4e c1 03 31 c0 5d c3 cc 0f 0b eb 02 0f 0b b8 ea ff ff ff 5d c3 cc 00 00 cc cc 00 00 cc cc 55 48 89 e5 <41> 57 41 56 41 55 41 54 53 b0 01 48 85 f6 0f 84 a4 01 00 00 48 89
RSP: 0018:ffffc9000e804000 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff817e5bf2
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff887c6568
RBP: ffffc9000e804000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92001d0080c
R13: dffffc0000000000 R14: ffffffff87e6b100 R15: 0000000000000000
FS: 00007fd0c55826c0(0000) GS:ffff8881f6800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc9000e803ff8 CR3: 0000000170ef7000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<#DF>
</#DF>
<TASK>
[<ffffffff81f281d1>] __kasan_check_read+0x11/0x20 mm/kasan/shadow.c:31
[<ffffffff817e5bf2>] instrument_atomic_read include/linux/instrumented.h:72 [inline]
[<ffffffff817e5bf2>] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
[<ffffffff817e5bf2>] cpumask_test_cpu include/linux/cpumask.h:506 [inline]
[<ffffffff817e5bf2>] cpu_online include/linux/cpumask.h:1092 [inline]
[<ffffffff817e5bf2>] trace_lock_acquire include/trace/events/lock.h:24 [inline]
[<ffffffff817e5bf2>] lock_acquire+0xe2/0x590 kernel/locking/lockdep.c:5632
[<ffffffff8563221e>] rcu_lock_acquire+0x2e/0x40 include/linux/rcupdate.h:306
[<ffffffff8561464d>] rcu_read_lock include/linux/rcupdate.h:747 [inline]
[<ffffffff8561464d>] ip6_pol_route+0x15d/0x1440 net/ipv6/route.c:2221
[<ffffffff85618120>] ip6_pol_route_output+0x50/0x80 net/ipv6/route.c:2606
[<ffffffff856f65b5>] pol_lookup_func include/net/ip6_fib.h:584 [inline]
[<ffffffff856f65b5>] fib6_rule_lookup+0x265/0x620 net/ipv6/fib6_rules.c:116
[<ffffffff85618009>] ip6_route_output_flags_noref+0x2d9/0x3a0 net/ipv6/route.c:2638
[<ffffffff8561821a>] ip6_route_output_flags+0xca/0x340 net/ipv6/route.c:2651
[<ffffffff838bd5a3>] ip6_route_output include/net/ip6_route.h:100 [inline]
[<ffffffff838bd5a3>] ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:473 [inline]
[<ffffffff838bd5a3>] ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:529 [inline]
[<ffffffff838bd5a3>] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline]
[<ffffffff838bd5a3>] ipvlan_queue_xmit+0xc33/0x1be0 drivers/net/ipvlan/ipvlan_core.c:677
[<ffffffff838c2909>] ipvlan_start_xmit+0x49/0x100 drivers/net/ipvlan/ipvlan_main.c:229
[<ffffffff84d03900>] netdev_start_xmit include/linux/netdevice.h:4966 [inline]
[<ffffffff84d03900>] xmit_one net/core/dev.c:3644 [inline]
[<ffffffff84d03900>] dev_hard_start_xmit+0x320/0x980 net/core/dev.c:3660
[<ffffffff84d080e2>] __dev_queue_xmit+0x16b2/0x3370 net/core/dev.c:4324
[<ffffffff855ce4cd>] dev_queue_xmit include/linux/netdevice.h:3067 [inline]
[<ffffffff855ce4cd>] neigh_hh_output include/net/neighbour.h:529 [inline]
[<ffffffff855ce4cd>] neigh_output include/net/neighbour.h:543 [inline]
[<ffffffff855ce4cd>] ip6_finish_output2+0x160d/0x1ae0 net/ipv6/ip6_output.c:139
[<ffffffff855b8616>] __ip6_finish_output net/ipv6/ip6_output.c:200 [inline]
[<ffffffff855b8616>] ip6_finish_output+0x6c6/0xb10 net/ipv6/ip6_output.c:211
[<ffffffff855b7e3c>] NF_HOOK_COND include/linux/netfilter.h:298 [inline]
[<ffffffff855b7e3c>] ip6_output+0x2bc/0x3d0 net/ipv6/ip6_output.c:232
[<ffffffff8575d27f>] dst_output include/net/dst.h:444 [inline]
[<ffffffff8575d27f>] ip6_local_out+0x10f/0x140 net/ipv6/output_core.c:161
[<ffffffff838bdae4>] ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:483 [inline]
[<ffffffff838bdae4>] ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:529 [inline]
[<ffffffff838bdae4>] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline]
[<ffffffff838bdae4>] ipvlan_queue_xmit+0x1174/0x1be0 drivers/net/ipvlan/ipvlan_core.c:677
[<ffffffff838c2909>] ipvlan_start_xmit+0x49/0x100 drivers/net/ipvlan/ipvlan_main.c:229
[<ffffffff84d03900>] netdev_start_xmit include/linux/netdevice.h:4966 [inline]
[<ffffffff84d03900>] xmit_one net/core/dev.c:3644 [inline]
[<ffffffff84d03900>] dev_hard_start_xmit+0x320/0x980 net/core/dev.c:3660
[<ffffffff84d080e2>] __dev_queue_xmit+0x16b2/0x3370 net/core/dev.c:4324
[<ffffffff855ce4cd>] dev_queue_xmit include/linux/netdevice.h:3067 [inline]
[<ffffffff855ce4cd>] neigh_hh_output include/net/neighbour.h:529 [inline]
[<ffffffff855ce4cd>] neigh_output include/net/neighbour.h:543 [inline]
[<ffffffff855ce4cd>] ip6_finish_output2+0x160d/0x1ae0 net/ipv6/ip6_output.c:139
[<ffffffff855b8616>] __ip6_finish_output net/ipv6/ip6_output.c:200 [inline]
[<ffffffff855b8616>] ip6_finish_output+0x6c6/0xb10 net/ipv6/ip6_output.c:211
[<ffffffff855b7e3c>] NF_HOOK_COND include/linux/netfilter.h:298 [inline]
[<ffffffff855b7e3c>] ip6_output+0x2bc/0x3d0 net/ipv6/ip6_output.c:232
[<ffffffff8575d27f>] dst_output include/net/dst.h:444 [inline]
[<ffffffff8575d27f>] ip6_local_out+0x10f/0x140 net/ipv6/output_core.c:161
[<ffffffff838bdae4>] ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:483 [inline]
[<ffffffff838bdae4>] ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:529 [inline]
[<ffffffff838bdae4>] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline]
[<ffffffff838bdae4>] ipvlan_queue_xmit+0x1174/0x1be0 drivers/net/ipvlan/ipvlan_core.c:677
[<ffffffff838c2909>] ipvlan_start_xmit+0x49/0x100 drivers/net/ipvlan/ipvlan_main.c:229
[<ffffffff84d03900>] netdev_start_xmit include/linux/netdevice.h:4966 [inline]
[<ffffffff84d03900>] xmit_one net/core/dev.c:3644 [inline]
[<ffffffff84d03900>] dev_hard_start_xmit+0x320/0x980 net/core/dev.c:3660
[<ffffffff84d080e2>] __dev_queue_xmit+0x16b2/0x3370 net/core/dev.c:4324
[<ffffffff855ce4cd>] dev_queue_xmit include/linux/netdevice.h:3067 [inline]
[<ffffffff855ce4cd>] neigh_hh_output include/net/neighbour.h:529 [inline]
[<ffffffff855ce4cd>] neigh_output include/net/neighbour.h:543 [inline]
[<ffffffff855ce4cd>] ip6_finish_output2+0x160d/0x1ae0 net/ipv6/ip6_output.c:139
[<ffffffff855b8616>] __ip6_finish_output net/ipv6/ip6_output.c:200 [inline]
[<ffffffff855b8616>] ip6_finish_output+0x6c6/0xb10 net/ipv6/ip6_output.c:211
[<ffffffff855b7e3c>] NF_HOOK_COND include/linux/netfilter.h:298 [inline]
[<ffffffff855b7e3c>] ip6_output+0x2bc/0x3d0 net/ipv6/ip6_output.c:232
[<ffffffff8575d27f>] dst_output include/net/dst.h:444 [inline]
[<ffffffff8575d27f>] ip6_local_out+0x10f/0x140 net/ipv6/output_core.c:161
[<ffffffff838bdae4>] ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:483 [inline]
[<ffffffff838bdae4>] ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:529 [inline]
[<ffffffff838bdae4>] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline]
[<ffffffff838bdae4>] ipvlan_queue_xmit+0x1174/0x1be0 drivers/net/ipvlan/ipvlan_core.c:677
[<ffffffff838c2909>] ipvlan_start_xmit+0x49/0x100 drivers/net/ipvlan/ipvlan_main.c:229
[<ffffffff84d03900>] netdev_start_xmit include/linux/netdevice.h:4966 [inline]
[<ffffffff84d03900>] xmit_one net/core/dev.c:3644 [inline]
[<ffffffff84d03900>] dev_hard_start_xmit+0x320/0x980 net/core/dev.c:3660
[<ffffffff84d080e2>] __dev_queue_xmit+0x16b2/0x3370 net/core/dev.c:4324
[<ffffffff855ce4cd>] dev_queue_xmit include/linux/netdevice.h:3067 [inline]
[<ffffffff855ce4cd>] neigh_hh_output include/net/neighbour.h:529 [inline]
[<ffffffff855ce4cd>] neigh_output include/net/neighbour.h:543 [inline]
[<ffffffff855ce4cd>] ip6_finish_output2+0x160d/0x1ae0 net/ipv6/ip6_output.c:139
[<ffffffff855b8616>] __ip6_finish_output net/ipv6/ip6_output.c:200 [inline]
[<ffffffff855b8616>] ip6_finish_output+0x6c6/0xb10 net/ipv6/ip6_output.c:211
[<ffffffff855b7e3c>] NF_HOOK_COND include/linux/netfilter.h:298 [inline]
[<ffffffff855b7e3c>] ip6_output+0x2bc/0x3d0 net/ipv6/ip6_output.c:232
[<ffffffff8575d27f>] dst_output include/net/dst.h:444 [inline]
[<ffffffff8575d27f>] ip6_local_out+0x10f/0x140 net/ipv6/output_core.c:161
[<ffffffff838bdae4>] ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:483 [inline]
[<ffffffff838bdae4>] ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:529 [inline]
[<ffffffff838bdae4>] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline]
[<ffffffff838bdae4>] ipvlan_queue_xmit+0x1174/0x1be0 drivers/net/ipvlan/ipvlan_core.c:677
[<ffffffff838c2909>] ipvlan_start_xmit+0x49/0x100 drivers/net/ipvlan/ipvlan_main.c:229
[<ffffffff84d03900>] netdev_start_xmit include/linux/netdevice.h:4966 [inline]
[<ffffffff84d03900>] xmit_one net/core/dev.c:3644 [inline]
[<ffffffff84d03900>] dev_hard_start_xmit+0x320/0x980 net/core/dev.c:3660
[<ffffffff84d080e2>] __dev_queue_xmit+0x16b2/0x3370 net/core/dev.c:4324
[<ffffffff84d4a65e>] dev_queue_xmit include/linux/netdevice.h:3067 [inline]
[<ffffffff84d4a65e>] neigh_resolve_output+0x64e/0x750 net/core/neighbour.c:1560
[<ffffffff855ce503>] neigh_output include/net/neighbour.h:545 [inline]
[<ffffffff855ce503>] ip6_finish_output2+0x1643/0x1ae0 net/ipv6/ip6_output.c:139
[<ffffffff855b8616>] __ip6_finish_output net/ipv6/ip6_output.c:200 [inline]
[<ffffffff855b8616>] ip6_finish_output+0x6c6/0xb10 net/ipv6/ip6_output.c:211
[<ffffffff855b7e3c>] NF_HOOK_COND include/linux/netfilter.h:298 [inline]
[<ffffffff855b7e3c>] ip6_output+0x2bc/0x3d0 net/ipv6/ip6_output.c:232
[<ffffffff855b9ce4>] dst_output include/net/dst.h:444 [inline]
[<ffffffff855b9ce4>] NF_HOOK include/linux/netfilter.h:309 [inline]
[<ffffffff855b9ce4>] ip6_xmit+0x11a4/0x1b20 net/ipv6/ip6_output.c:352
[<ffffffff8597984e>] sctp_v6_xmit+0x9ae/0x1230 net/sctp/ipv6.c:250
[<ffffffff8594623e>] sctp_packet_transmit+0x25de/0x2bc0 net/sctp/output.c:653
[<ffffffff858f5142>] sctp_packet_singleton+0x202/0x310 net/sctp/outqueue.c:783
[<ffffffff858ea411>] sctp_outq_flush_ctrl net/sctp/outqueue.c:914 [inline]
[<ffffffff858ea411>] sctp_outq_flush+0x661/0x3d40 net/sctp/outqueue.c:1212
[<ffffffff858f02f9>] sctp_outq_uncork+0x79/0xb0 net/sctp/outqueue.c:764
[<ffffffff8589f060>] sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline]
[<ffffffff8589f060>] sctp_do_sm+0x55c0/0x5c30 net/sctp/sm_sideeffect.c:1170
[<ffffffff85941567>] sctp_primitive_ASSOCIATE+0x97/0xc0 net/sctp/primitive.c:73
[<ffffffff859408b2>] sctp_sendmsg_to_asoc+0xf62/0x17b0 net/sctp/socket.c:1839
[<ffffffff85910b5e>] sctp_sendmsg+0x212e/0x33b0 net/sctp/socket.c:2029
[<ffffffff8544d559>] inet_sendmsg+0x149/0x310 net/ipv4/af_inet.c:849
[<ffffffff84c6c4d2>] sock_sendmsg_nosec net/socket.c:716 [inline]
[<ffffffff84c6c4d2>] sock_sendmsg net/socket.c:736 [inline]
[<ffffffff84c6c4d2>] ____sys_sendmsg+0x572/0x8c0 net/socket.c:2504
[<ffffffff84c6ca91>] ___sys_sendmsg net/socket.c:2558 [inline]
[<ffffffff84c6ca91>] __sys_sendmsg+0x271/0x360 net/socket.c:2587
[<ffffffff84c6cbff>] __do_sys_sendmsg net/socket.c:2596 [inline]
[<ffffffff84c6cbff>] __se_sys_sendmsg net/socket.c:2594 [inline]
[<ffffffff84c6cbff>] __x64_sys_sendmsg+0x7f/0x90 net/socket.c:2594
[<ffffffff85b32553>] do_syscall_x64 arch/x86/entry/common.c:51 [inline]
[<ffffffff85b32553>] do_syscall_64+0x53/0x80 arch/x86/entry/common.c:84
[<ffffffff85c00087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

The Linux kernel CVE team has assigned CVE-2023-52796 to this issue.

Affected and fixed versions
===========================

	Issue introduced in 3.19 with commit 2ad7bf363841 and fixed in 4.19.300 with commit 4f7f850611aa
	Issue introduced in 3.19 with commit 2ad7bf363841 and fixed in 5.4.262 with commit 4d2d30f0792b
	Issue introduced in 3.19 with commit 2ad7bf363841 and fixed in 5.10.202 with commit 43b781e7cb5c
	Issue introduced in 3.19 with commit 2ad7bf363841 and fixed in 5.15.140 with commit 1f64cad3ac38
	Issue introduced in 3.19 with commit 2ad7bf363841 and fixed in 6.1.64 with commit 732a67ca4368
	Issue introduced in 3.19 with commit 2ad7bf363841 and fixed in 6.5.13 with commit 8872dc638c24
	Issue introduced in 3.19 with commit 2ad7bf363841 and fixed in 6.6.3 with commit 03cddc4df8c6
	Issue introduced in 3.19 with commit 2ad7bf363841 and fixed in 6.7 with commit 18f039428c7d

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2023-52796
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	drivers/net/ipvlan/ipvlan_core.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/4f7f850611aa27aaaf1bf5687702ad2240ae442a
	https://git.kernel.org/stable/c/4d2d30f0792b47908af64c4d02ed1ee25ff50542
	https://git.kernel.org/stable/c/43b781e7cb5cd0b435de276111953bf2bacd1f02
	https://git.kernel.org/stable/c/1f64cad3ac38ac5978b53c40e6c5e6fd3477c68f
	https://git.kernel.org/stable/c/732a67ca436887b594ebc43bb5a04ffb0971a760
	https://git.kernel.org/stable/c/8872dc638c24bb774cd2224a69d72a7f661a4d56
	https://git.kernel.org/stable/c/03cddc4df8c6be47fd27c8f8b87e5f9a989e1458
	https://git.kernel.org/stable/c/18f039428c7df183b09c69ebf10ffd4e521035d2