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Ziyang Xuan cf71699d62 can: raw: raw_setsockopt(): fix raw_rcv panic for sock UAF
commit 54f93336d000229f72c26d8a3f69dd256b744528 upstream.

We get a bug during ltp can_filter test as following.

===========================================
[60919.264984] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
[60919.265223] PGD 8000003dda726067 P4D 8000003dda726067 PUD 3dda727067 PMD 0
[60919.265443] Oops: 0000 [#1] SMP PTI
[60919.265550] CPU: 30 PID: 3638365 Comm: can_filter Kdump: loaded Tainted: G        W         4.19.90+ #1
[60919.266068] RIP: 0010:selinux_socket_sock_rcv_skb+0x3e/0x200
[60919.293289] RSP: 0018:ffff8d53bfc03cf8 EFLAGS: 00010246
[60919.307140] RAX: 0000000000000000 RBX: 000000000000001d RCX: 0000000000000007
[60919.320756] RDX: 0000000000000001 RSI: ffff8d5104a8ed00 RDI: ffff8d53bfc03d30
[60919.334319] RBP: ffff8d9338056800 R08: ffff8d53bfc29d80 R09: 0000000000000001
[60919.347969] R10: ffff8d53bfc03ec0 R11: ffffb8526ef47c98 R12: ffff8d53bfc03d30
[60919.350320] perf: interrupt took too long (3063 > 2500), lowering kernel.perf_event_max_sample_rate to 65000
[60919.361148] R13: 0000000000000001 R14: ffff8d53bcf90000 R15: 0000000000000000
[60919.361151] FS:  00007fb78b6b3600(0000) GS:ffff8d53bfc00000(0000) knlGS:0000000000000000
[60919.400812] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[60919.413730] CR2: 0000000000000010 CR3: 0000003e3f784006 CR4: 00000000007606e0
[60919.426479] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[60919.439339] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[60919.451608] PKRU: 55555554
[60919.463622] Call Trace:
[60919.475617]  <IRQ>
[60919.487122]  ? update_load_avg+0x89/0x5d0
[60919.498478]  ? update_load_avg+0x89/0x5d0
[60919.509822]  ? account_entity_enqueue+0xc5/0xf0
[60919.520709]  security_sock_rcv_skb+0x2a/0x40
[60919.531413]  sk_filter_trim_cap+0x47/0x1b0
[60919.542178]  ? kmem_cache_alloc+0x38/0x1b0
[60919.552444]  sock_queue_rcv_skb+0x17/0x30
[60919.562477]  raw_rcv+0x110/0x190 [can_raw]
[60919.572539]  can_rcv_filter+0xbc/0x1b0 [can]
[60919.582173]  can_receive+0x6b/0xb0 [can]
[60919.591595]  can_rcv+0x31/0x70 [can]
[60919.600783]  __netif_receive_skb_one_core+0x5a/0x80
[60919.609864]  process_backlog+0x9b/0x150
[60919.618691]  net_rx_action+0x156/0x400
[60919.627310]  ? sched_clock_cpu+0xc/0xa0
[60919.635714]  __do_softirq+0xe8/0x2e9
[60919.644161]  do_softirq_own_stack+0x2a/0x40
[60919.652154]  </IRQ>
[60919.659899]  do_softirq.part.17+0x4f/0x60
[60919.667475]  __local_bh_enable_ip+0x60/0x70
[60919.675089]  __dev_queue_xmit+0x539/0x920
[60919.682267]  ? finish_wait+0x80/0x80
[60919.689218]  ? finish_wait+0x80/0x80
[60919.695886]  ? sock_alloc_send_pskb+0x211/0x230
[60919.702395]  ? can_send+0xe5/0x1f0 [can]
[60919.708882]  can_send+0xe5/0x1f0 [can]
[60919.715037]  raw_sendmsg+0x16d/0x268 [can_raw]

It's because raw_setsockopt() concurrently with
unregister_netdevice_many(). Concurrent scenario as following.

	cpu0						cpu1
raw_bind
raw_setsockopt					unregister_netdevice_many
						unlist_netdevice
dev_get_by_index				raw_notifier
raw_enable_filters				......
can_rx_register
can_rcv_list_find(..., net->can.rx_alldev_list)

......

sock_close
raw_release(sock_a)

......

can_receive
can_rcv_filter(net->can.rx_alldev_list, ...)
raw_rcv(skb, sock_a)
BUG

After unlist_netdevice(), dev_get_by_index() return NULL in
raw_setsockopt(). Function raw_enable_filters() will add sock
and can_filter to net->can.rx_alldev_list. Then the sock is closed.
Followed by, we sock_sendmsg() to a new vcan device use the same
can_filter. Protocol stack match the old receiver whose sock has
been released on net->can.rx_alldev_list in can_rcv_filter().
Function raw_rcv() uses the freed sock. UAF BUG is triggered.

We can find that the key issue is that net_device has not been
protected in raw_setsockopt(). Use rtnl_lock to protect net_device
in raw_setsockopt().

Fixes: c18ce101f2 ("[CAN]: Add raw protocol")
Link: https://lore.kernel.org/r/20210722070819.1048263-1-william.xuanziyang@huawei.com
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05 18:03:15 +02:00
arch x86/kvm: fix vcpu-id indexed array sizes 2024-07-05 18:03:01 +02:00
block init: add dsm gpl source 2024-07-05 18:00:04 +02:00
certs certs: add 'x509_revocation_list' to gitignore 2021-07-20 16:05:35 +02:00
crypto init: add dsm gpl source 2024-07-05 18:00:04 +02:00
Documentation init: add dsm gpl source 2024-07-05 18:00:04 +02:00
drivers ACPI: DPTF: Fix reading of attributes 2024-07-05 18:02:57 +02:00
fs ocfs2: issue zeroout to EOF blocks 2024-07-05 18:03:15 +02:00
include init: add dsm gpl source 2024-07-05 18:00:04 +02:00
init init: add dsm gpl source 2024-07-05 18:00:04 +02:00
ipc ipc/mqueue, msg, sem: avoid relying on a stack reference past its expiry 2021-05-26 12:06:54 +02:00
kernel init: add dsm gpl source 2024-07-05 18:00:04 +02:00
lib init: add dsm gpl source 2024-07-05 18:00:04 +02:00
LICENSES LICENSES/deprecated: add Zlib license text 2020-09-16 14:33:49 +02:00
mm init: add dsm gpl source 2024-07-05 18:00:04 +02:00
net can: raw: raw_setsockopt(): fix raw_rcv panic for sock UAF 2024-07-05 18:03:15 +02:00
samples samples/bpf: Fix the error return code of xdp_redirect's main() 2021-07-14 16:56:23 +02:00
scripts init: add dsm gpl source 2024-07-05 18:00:04 +02:00
security init: add dsm gpl source 2024-07-05 18:00:04 +02:00
sound ALSA: pcm: Fix mmap capability check 2021-07-28 14:35:43 +02:00
SynoBuildConf init: add dsm gpl source 2024-07-05 18:00:04 +02:00
synology init: add dsm gpl source 2024-07-05 18:00:04 +02:00
tools init: add dsm gpl source 2024-07-05 18:00:04 +02:00
usr Merge branch 'work.fdpic' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 13:29:39 -07:00
virt KVM: add missing compat KVM_CLEAR_DIRTY_LOG 2024-07-05 18:03:15 +02:00
.clang-format init: add dsm gpl source 2024-07-05 18:00:04 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore kbuild: generate Module.symvers only when vmlinux exists 2021-05-19 10:12:59 +02:00
.mailmap mailmap: add two more addresses of Uwe Kleine-König 2020-12-06 10:19:07 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Jason Cooper to CREDITS 2020-11-30 10:20:34 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS init: add dsm gpl source 2024-07-05 18:00:04 +02:00
Makefile init: add dsm gpl source 2024-07-05 18:00:04 +02:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.