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Ilya Shchipletsov 78a110332a netrom: check buffer length before accessing it
[ Upstream commit a4fd163aed2edd967a244499754dec991d8b4c7d ]

Syzkaller reports an uninit value read from ax25cmp when sending raw message
through ieee802154 implementation.

=====================================================
BUG: KMSAN: uninit-value in ax25cmp+0x3a5/0x460 net/ax25/ax25_addr.c:119
 ax25cmp+0x3a5/0x460 net/ax25/ax25_addr.c:119
 nr_dev_get+0x20e/0x450 net/netrom/nr_route.c:601
 nr_route_frame+0x1a2/0xfc0 net/netrom/nr_route.c:774
 nr_xmit+0x5a/0x1c0 net/netrom/nr_dev.c:144
 __netdev_start_xmit include/linux/netdevice.h:4940 [inline]
 netdev_start_xmit include/linux/netdevice.h:4954 [inline]
 xmit_one net/core/dev.c:3548 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3564
 __dev_queue_xmit+0x33b8/0x5130 net/core/dev.c:4349
 dev_queue_xmit include/linux/netdevice.h:3134 [inline]
 raw_sendmsg+0x654/0xc10 net/ieee802154/socket.c:299
 ieee802154_sock_sendmsg+0x91/0xc0 net/ieee802154/socket.c:96
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmsg net/socket.c:2667 [inline]
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 slab_post_alloc_hook+0x129/0xa70 mm/slab.h:768
 slab_alloc_node mm/slub.c:3478 [inline]
 kmem_cache_alloc_node+0x5e9/0xb10 mm/slub.c:3523
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:560
 __alloc_skb+0x318/0x740 net/core/skbuff.c:651
 alloc_skb include/linux/skbuff.h:1286 [inline]
 alloc_skb_with_frags+0xc8/0xbd0 net/core/skbuff.c:6334
 sock_alloc_send_pskb+0xa80/0xbf0 net/core/sock.c:2780
 sock_alloc_send_skb include/net/sock.h:1884 [inline]
 raw_sendmsg+0x36d/0xc10 net/ieee802154/socket.c:282
 ieee802154_sock_sendmsg+0x91/0xc0 net/ieee802154/socket.c:96
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmsg net/socket.c:2667 [inline]
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

CPU: 0 PID: 5037 Comm: syz-executor166 Not tainted 6.7.0-rc7-syzkaller-00003-gfbafc3e621c3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
=====================================================

This issue occurs because the skb buffer is too small, and it's actual
allocation is aligned. This hides an actual issue, which is that nr_route_frame
does not validate the buffer size before using it.

Fix this issue by checking skb->len before accessing any fields in skb->data.

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Co-developed-by: Nikita Marushkin <hfggklm@gmail.com>
Signed-off-by: Nikita Marushkin <hfggklm@gmail.com>
Signed-off-by: Ilya Shchipletsov <rabbelkin@mail.ru>
Link: https://patch.msgid.link/20241219082308.3942-1-rabbelkin@mail.ru
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-09 13:30:01 +01:00
arch x86/hyperv: Fix hv tsc page based sched_clock for hibernation 2025-01-09 13:29:56 +01:00
block blk-mq: register cpuhp callback after hctx is added to xarray table 2025-01-02 10:30:52 +01:00
certs
crypto crypto: api - Add crypto_clone_tfm 2024-12-14 19:53:51 +01:00
Documentation Documentation: PM: Clarify pm_runtime_resume_and_get() return value 2024-12-19 18:08:56 +01:00
drivers net: Fix netns for ip_tunnel_init_flow() 2025-01-09 13:30:00 +01:00
fs btrfs: fix use-after-free in btrfs_encoded_read_endio() 2025-01-09 13:29:56 +01:00
include ipip,ip_tunnel,sit: Add FOU support for externally controlled ipip devices 2025-01-09 13:30:00 +01:00
init initramfs: avoid filename buffer overrun 2024-12-14 19:53:14 +01:00
io_uring io_uring/sqpoll: fix sqpoll error handling races 2025-01-02 10:30:54 +01:00
ipc ipc: fix memleak if msg_init_ns failed in create_ipc_ns 2024-12-14 19:54:06 +01:00
kernel tracing: Have process_string() also allow arrays 2025-01-09 13:29:56 +01:00
lib lib: stackinit: hide never-taken branch from compiler 2024-12-14 19:54:37 +01:00
LICENSES
mm vmalloc: fix accounting with i915 2025-01-02 10:30:53 +01:00
net netrom: check buffer length before accessing it 2025-01-09 13:30:01 +01:00
rust rust: macros: provide correct provenance when constructing THIS_MODULE 2024-10-17 15:22:24 +02:00
samples samples/bpf: Fix a resource leak 2024-12-14 19:54:40 +01:00
scripts modpost: Add .irqentry.text to OTHER_SECTIONS 2024-12-14 19:54:35 +01:00
security selinux: ignore unknown extended permissions 2025-01-09 13:29:56 +01:00
sound ALSA: hda/realtek: Fix spelling mistake "Firelfy" -> "Firefly" 2025-01-02 10:30:55 +01:00
tools stddef: make __struct_group() UAPI C++-friendly 2025-01-02 10:30:51 +01:00
usr
virt KVM: Fix a data race on last_boosted_vcpu in kvm_vcpu_on_spin() 2024-06-27 13:46:21 +02:00
.clang-format
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes
.gitignore Remove *.orig pattern from .gitignore 2024-10-17 15:21:15 +02:00
.mailmap 9 hotfixes. 6 for MM, 3 for other areas. Four of these patches address 2022-12-10 17:10:52 -08:00
.rustfmt.toml
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Remove Michal Marek from Kbuild maintainers 2022-11-16 14:53:00 +09:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig
MAINTAINERS MAINTAINERS: add leah to 6.1 MAINTAINERS file 2024-05-17 11:56:16 +02:00
Makefile Linux 6.1.123 2025-01-02 10:30:56 +01:00
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