Subject: CVE-2022-48810: ipmr,ip6mr: acquire RTNL before calling ip[6]mr_free_table() on failure path

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

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

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

ipmr,ip6mr: acquire RTNL before calling ip[6]mr_free_table() on failure path

ip[6]mr_free_table() can only be called under RTNL lock.

RTNL: assertion failed at net/core/dev.c (10367)
WARNING: CPU: 1 PID: 5890 at net/core/dev.c:10367 unregister_netdevice_many+0x1246/0x1850 net/core/dev.c:10367
Modules linked in:
CPU: 1 PID: 5890 Comm: syz-executor.2 Not tainted 5.16.0-syzkaller-11627-g422ee58dc0ef #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:unregister_netdevice_many+0x1246/0x1850 net/core/dev.c:10367
Code: 0f 85 9b ee ff ff e8 69 07 4b fa ba 7f 28 00 00 48 c7 c6 00 90 ae 8a 48 c7 c7 40 90 ae 8a c6 05 6d b1 51 06 01 e8 8c 90 d8 01 <0f> 0b e9 70 ee ff ff e8 3e 07 4b fa 4c 89 e7 e8 86 2a 59 fa e9 ee
RSP: 0018:ffffc900046ff6e0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff888050f51d00 RSI: ffffffff815fa008 RDI: fffff520008dfece
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815f3d6e R11: 0000000000000000 R12: 00000000fffffff4
R13: dffffc0000000000 R14: ffffc900046ff750 R15: ffff88807b7dc000
FS:  00007f4ab736e700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fee0b4f8990 CR3: 000000001e7d2000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 mroute_clean_tables+0x244/0xb40 net/ipv6/ip6mr.c:1509
 ip6mr_free_table net/ipv6/ip6mr.c:389 [inline]
 ip6mr_rules_init net/ipv6/ip6mr.c:246 [inline]
 ip6mr_net_init net/ipv6/ip6mr.c:1306 [inline]
 ip6mr_net_init+0x3f0/0x4e0 net/ipv6/ip6mr.c:1298
 ops_init+0xaf/0x470 net/core/net_namespace.c:140
 setup_net+0x54f/0xbb0 net/core/net_namespace.c:331
 copy_net_ns+0x318/0x760 net/core/net_namespace.c:475
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178
 copy_process+0x2e0c/0x7300 kernel/fork.c:2167
 kernel_clone+0xe7/0xab0 kernel/fork.c:2555
 __do_sys_clone+0xc8/0x110 kernel/fork.c:2672
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f4ab89f9059
Code: Unable to access opcode bytes at RIP 0x7f4ab89f902f.
RSP: 002b:00007f4ab736e118 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f4ab8b0bf60 RCX: 00007f4ab89f9059
RDX: 0000000020000280 RSI: 0000000020000270 RDI: 0000000040200000
RBP: 00007f4ab8a5308d R08: 0000000020000300 R09: 0000000020000300
R10: 00000000200002c0 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffc3977cc1f R14: 00007f4ab736e300 R15: 0000000000022000
 </TASK>

The Linux kernel CVE team has assigned CVE-2022-48810 to this issue.

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

	Issue introduced in 4.0 with commit f243e5a7859a and fixed in 4.9.302 with commit 80c529322600
	Issue introduced in 4.0 with commit f243e5a7859a and fixed in 4.14.267 with commit b541845dfc4e
	Issue introduced in 4.0 with commit f243e5a7859a and fixed in 4.19.230 with commit 12b6703e9546
	Issue introduced in 4.0 with commit f243e5a7859a and fixed in 5.4.180 with commit 16dcfde98a25
	Issue introduced in 4.0 with commit f243e5a7859a and fixed in 5.10.101 with commit 09ac0fcb0a82
	Issue introduced in 4.0 with commit f243e5a7859a and fixed in 5.15.24 with commit 3cab045c99db
	Issue introduced in 4.0 with commit f243e5a7859a and fixed in 5.16.10 with commit feb9597e2275
	Issue introduced in 4.0 with commit f243e5a7859a and fixed in 5.17 with commit 5611a00697c8

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-2022-48810
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:
	net/ipv4/ipmr.c
	net/ipv6/ip6mr.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/80c529322600dfb1f985b5e3f14c3c6f522ce154
	https://git.kernel.org/stable/c/b541845dfc4e7df551955e70deec0921d6b297c3
	https://git.kernel.org/stable/c/12b6703e9546902c56b4b9048b893ad49d62bdd4
	https://git.kernel.org/stable/c/16dcfde98a25340ff0f7879a16bea141d824a196
	https://git.kernel.org/stable/c/09ac0fcb0a82d647f2c61d3d488d367b7ee5bd51
	https://git.kernel.org/stable/c/3cab045c99dbb9a94eb2d1d405f399916eec698a
	https://git.kernel.org/stable/c/feb9597e22755dce782aae26ac0590c06737e049
	https://git.kernel.org/stable/c/5611a00697c8ecc5aad04392bea629e9d6a20463