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Dong Chenchen 6d41d4fe28 net: xfrm: skip policies marked as dead while reinserting policies
BUG: KASAN: slab-use-after-free in xfrm_policy_inexact_list_reinsert+0xb6/0x430
Read of size 1 at addr ffff8881051f3bf8 by task ip/668

CPU: 2 PID: 668 Comm: ip Not tainted 6.5.0-rc5-00182-g25aa0bebba72-dirty #64
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x72/0xa0
 print_report+0xd0/0x620
 kasan_report+0xb6/0xf0
 xfrm_policy_inexact_list_reinsert+0xb6/0x430
 xfrm_policy_inexact_insert_node.constprop.0+0x537/0x800
 xfrm_policy_inexact_alloc_chain+0x23f/0x320
 xfrm_policy_inexact_insert+0x6b/0x590
 xfrm_policy_insert+0x3b1/0x480
 xfrm_add_policy+0x23c/0x3c0
 xfrm_user_rcv_msg+0x2d0/0x510
 netlink_rcv_skb+0x10d/0x2d0
 xfrm_netlink_rcv+0x49/0x60
 netlink_unicast+0x3fe/0x540
 netlink_sendmsg+0x528/0x970
 sock_sendmsg+0x14a/0x160
 ____sys_sendmsg+0x4fc/0x580
 ___sys_sendmsg+0xef/0x160
 __sys_sendmsg+0xf7/0x1b0
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x73/0xdd

The root cause is:

cpu 0			cpu1
xfrm_dump_policy
xfrm_policy_walk
list_move_tail
			xfrm_add_policy
			... ...
			xfrm_policy_inexact_list_reinsert
			list_for_each_entry_reverse
				if (!policy->bydst_reinsert)
				//read non-existent policy
xfrm_dump_policy_done
xfrm_policy_walk_done
list_del(&walk->walk.all);

If dump_one_policy() returns err (triggered by netlink socket),
xfrm_policy_walk() will move walk initialized by socket to list
net->xfrm.policy_all. so this socket becomes visible in the global
policy list. The head *walk can be traversed when users add policies
with different prefixlen and trigger xfrm_policy node merge.

The issue can also be triggered by policy list traversal while rehashing
and flushing policies.

It can be fixed by skip such "policies" with walk.dead set to 1.

Fixes: 9cf545ebd5 ("xfrm: policy: store inexact policies in a tree ordered by destination address")
Fixes: 12a169e7d8 ("ipsec: Put dumpers on the dump list")
Signed-off-by: Dong Chenchen <dongchenchen2@huawei.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2023-09-05 11:38:14 +02:00
arch Networking changes for 6.6. 2023-08-29 11:33:01 -07:00
block v6.6-vfs.super 2023-08-28 11:04:18 -07:00
certs certs: Reference revocation list for all keyrings 2023-08-17 20:12:41 +00:00
crypto This update includes the following changes: 2023-08-29 11:23:29 -07:00
Documentation docs: netdev: update the netdev infra URLs 2023-09-04 10:59:13 +01:00
drivers Revert "net: macsec: preserve ingress frame ordering" 2023-09-05 10:56:55 +02:00
fs pstore updates for v6.6-rc1 2023-08-28 12:36:04 -07:00
include af_unix: Fix msg_controllen test in scm_pidfd_recv() for MSG_CMSG_COMPAT. 2023-09-04 11:00:17 +01:00
init Scheduler changes for v6.6: 2023-08-28 16:43:39 -07:00
io_uring New code for 6.6: 2023-08-28 11:59:52 -07:00
ipc mqueue: convert to ctime accessor functions 2023-07-24 10:30:07 +02:00
kernel netfilter: nf_tables: Audit log rule reset 2023-08-31 01:29:28 +02:00
lib Networking changes for 6.6. 2023-08-29 11:33:01 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm Networking changes for 6.6. 2023-08-29 11:33:01 -07:00
net net: xfrm: skip policies marked as dead while reinserting policies 2023-09-05 11:38:14 +02:00
rust Rust changes for v6.6 2023-08-29 08:19:46 -07:00
samples Networking changes for 6.6. 2023-08-29 11:33:01 -07:00
scripts bpf, docs: Fix invalid escape sequence warnings in bpf_doc.py 2023-08-31 13:56:31 +02:00
security Networking changes for 6.6. 2023-08-29 11:33:01 -07:00
sound regmap: Updates for v6.6 2023-08-29 09:26:04 -07:00
tools selftests: fib_tests: Add multipath list receive tests 2023-09-01 08:11:51 +01:00
usr initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP 2023-06-06 17:54:49 +09:00
virt KVM: Grab a reference to KVM for VM and vCPU stats file descriptors 2023-07-29 11:05:28 -04:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.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 Revert ".gitignore: ignore *.cover and *.mbx" 2023-07-04 15:05:12 -07:00
.mailmap mailmap: add entries for Simon Horman 2023-08-16 09:53:10 +01:00
.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 - Address -Wmissing-prototype warnings 2023-06-26 16:43:54 -07:00
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 Networking changes for 6.6. 2023-08-29 11:33:01 -07:00
Makefile Rust changes for v6.6 2023-08-29 08:19:46 -07:00
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.