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Kuniyuki Iwashima e3f9bed9be llc: Drop support for ETH_P_TR_802_2.
syzbot reported an uninit-value bug below. [0]

llc supports ETH_P_802_2 (0x0004) and used to support ETH_P_TR_802_2
(0x0011), and syzbot abused the latter to trigger the bug.

  write$tun(r0, &(0x7f0000000040)={@val={0x0, 0x11}, @val, @mpls={[], @llc={@snap={0xaa, 0x1, ')', "90e5dd"}}}}, 0x16)

llc_conn_handler() initialises local variables {saddr,daddr}.mac
based on skb in llc_pdu_decode_sa()/llc_pdu_decode_da() and passes
them to __llc_lookup().

However, the initialisation is done only when skb->protocol is
htons(ETH_P_802_2), otherwise, __llc_lookup_established() and
__llc_lookup_listener() will read garbage.

The missing initialisation existed prior to commit 211ed86510
("net: delete all instances of special processing for token ring").

It removed the part to kick out the token ring stuff but forgot to
close the door allowing ETH_P_TR_802_2 packets to sneak into llc_rcv().

Let's remove llc_tr_packet_type and complete the deprecation.

[0]:
BUG: KMSAN: uninit-value in __llc_lookup_established+0xe9d/0xf90
 __llc_lookup_established+0xe9d/0xf90
 __llc_lookup net/llc/llc_conn.c:611 [inline]
 llc_conn_handler+0x4bd/0x1360 net/llc/llc_conn.c:791
 llc_rcv+0xfbb/0x14a0 net/llc/llc_input.c:206
 __netif_receive_skb_one_core net/core/dev.c:5527 [inline]
 __netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5641
 netif_receive_skb_internal net/core/dev.c:5727 [inline]
 netif_receive_skb+0x58/0x660 net/core/dev.c:5786
 tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1555
 tun_get_user+0x53af/0x66d0 drivers/net/tun.c:2002
 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048
 call_write_iter include/linux/fs.h:2020 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x8ef/0x1490 fs/read_write.c:584
 ksys_write+0x20f/0x4c0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x93/0xd0 fs/read_write.c:646
 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

Local variable daddr created at:
 llc_conn_handler+0x53/0x1360 net/llc/llc_conn.c:783
 llc_rcv+0xfbb/0x14a0 net/llc/llc_input.c:206

CPU: 1 PID: 5004 Comm: syz-executor994 Not tainted 6.6.0-syzkaller-14500-g1c41041124bd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023

Fixes: 211ed86510 ("net: delete all instances of special processing for token ring")
Reported-by: syzbot+b5ad66046b913bc04c6f@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=b5ad66046b913bc04c6f
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240119015515.61898-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-01-19 21:30:09 -08:00
arch RTC for 6.8 2024-01-18 17:25:39 -08:00
block for-6.8/block-2024-01-08 2024-01-11 13:58:04 -08:00
certs This update includes the following changes: 2023-11-02 16:15:30 -10:00
crypto crypto: scomp - fix req->dst buffer overflow 2023-12-29 11:25:56 +08:00
Documentation This cycle, I2C removes the currently unused CLASS_DDC support 2024-01-18 17:29:01 -08:00
drivers bnxt_en: Fix possible crash after creating sw mqprio TCs 2024-01-19 21:15:13 -08:00
fs More eventfs fixes and a seq_buf fix for 6.8: 2024-01-18 14:45:33 -08:00
include llc: Drop support for ETH_P_TR_802_2. 2024-01-19 21:30:09 -08:00
init Driver core changes for 6.8-rc1 2024-01-18 09:48:40 -08:00
io_uring Generic: 2024-01-17 13:03:37 -08:00
ipc shm: Slim down dependencies 2023-12-20 19:26:31 -05:00
kernel Including fixes from bpf and netfilter. 2024-01-18 17:33:50 -08:00
lib cxl for v6.8 2024-01-18 16:22:43 -08:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm memblock: code readability improvement 2024-01-18 16:46:18 -08:00
net llc: Drop support for ETH_P_TR_802_2. 2024-01-19 21:30:09 -08:00
rust Rust changes for v6.8 2024-01-11 13:05:41 -08:00
samples tracing updates for 6.8: 2024-01-18 14:35:29 -08:00
scripts Char/Misc and other Driver changes for 6.8-rc1 2024-01-17 16:47:17 -08:00
security misc cleanups (the part that hadn't been picked by individual fs trees) 2024-01-11 20:23:50 -08:00
sound This cycle, I2C removes the currently unused CLASS_DDC support 2024-01-18 17:29:01 -08:00
tools selftests: bonding: Increase timeout to 1200s 2024-01-19 21:12:31 -08:00
usr usr/Kconfig: fix typos of "its" 2023-12-20 15:02:58 -08:00
virt Generic: 2024-01-17 13:03:37 -08:00
.clang-format clang-format: Update with v6.7-rc4's for_each macro list 2023-12-08 23:54:38 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rpm-pkg: generate kernel.spec in rpmbuild/SPECS/ 2023-10-03 20:49:09 +09:00
.mailmap Char/Misc and other Driver changes for 6.8-rc1 2024-01-17 16:47:17 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS Including fixes from bpf and netfilter. 2024-01-18 17:33:50 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Including fixes from bpf and netfilter. 2024-01-18 17:33:50 -08:00
Makefile Quite a lot of kexec work this time around. Many singleton patches in 2024-01-09 11:46:20 -08:00
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.