Taehee Yoo 9fe54cf418 tipc: fix ordering of tipc module init and exit routine
[ Upstream commit 9cf1cd8ee3ee09ef2859017df2058e2f53c5347f ]

In order to set/get/dump, the tipc uses the generic netlink
infrastructure. So, when tipc module is inserted, init function
calls genl_register_family().
After genl_register_family(), set/get/dump commands are immediately
allowed and these callbacks internally use the net_generic.
net_generic is allocated by register_pernet_device() but this
is called after genl_register_family() in the __init function.
So, these callbacks would use un-initialized net_generic.

Test commands:
    #SHELL1
    while :
    do
        modprobe tipc
        modprobe -rv tipc
    done

    #SHELL2
    while :
    do
        tipc link list
    done

Splat looks like:
[   59.616322][ T2788] kasan: CONFIG_KASAN_INLINE enabled
[   59.617234][ T2788] kasan: GPF could be caused by NULL-ptr deref or user memory access
[   59.618398][ T2788] general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[   59.619389][ T2788] CPU: 3 PID: 2788 Comm: tipc Not tainted 5.4.0+ #194
[   59.620231][ T2788] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   59.621428][ T2788] RIP: 0010:tipc_bcast_get_broadcast_mode+0x131/0x310 [tipc]
[   59.622379][ T2788] Code: c7 c6 ef 8b 38 c0 65 ff 0d 84 83 c9 3f e8 d7 a5 f2 e3 48 8d bb 38 11 00 00 48 b8 00 00 00 00
[   59.622550][ T2780] NET: Registered protocol family 30
[   59.624627][ T2788] RSP: 0018:ffff88804b09f578 EFLAGS: 00010202
[   59.624630][ T2788] RAX: dffffc0000000000 RBX: 0000000000000011 RCX: 000000008bc66907
[   59.624631][ T2788] RDX: 0000000000000229 RSI: 000000004b3cf4cc RDI: 0000000000001149
[   59.624633][ T2788] RBP: ffff88804b09f588 R08: 0000000000000003 R09: fffffbfff4fb3df1
[   59.624635][ T2788] R10: fffffbfff50318f8 R11: ffff888066cadc18 R12: ffffffffa6cc2f40
[   59.624637][ T2788] R13: 1ffff11009613eba R14: ffff8880662e9328 R15: ffff8880662e9328
[   59.624639][ T2788] FS:  00007f57d8f7b740(0000) GS:ffff88806cc00000(0000) knlGS:0000000000000000
[   59.624645][ T2788] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   59.625875][ T2780] tipc: Started in single node mode
[   59.626128][ T2788] CR2: 00007f57d887a8c0 CR3: 000000004b140002 CR4: 00000000000606e0
[   59.633991][ T2788] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   59.635195][ T2788] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   59.636478][ T2788] Call Trace:
[   59.637025][ T2788]  tipc_nl_add_bc_link+0x179/0x1470 [tipc]
[   59.638219][ T2788]  ? lock_downgrade+0x6e0/0x6e0
[   59.638923][ T2788]  ? __tipc_nl_add_link+0xf90/0xf90 [tipc]
[   59.639533][ T2788]  ? tipc_nl_node_dump_link+0x318/0xa50 [tipc]
[   59.640160][ T2788]  ? mutex_lock_io_nested+0x1380/0x1380
[   59.640746][ T2788]  tipc_nl_node_dump_link+0x4fd/0xa50 [tipc]
[   59.641356][ T2788]  ? tipc_nl_node_reset_link_stats+0x340/0x340 [tipc]
[   59.642088][ T2788]  ? __skb_ext_del+0x270/0x270
[   59.642594][ T2788]  genl_lock_dumpit+0x85/0xb0
[   59.643050][ T2788]  netlink_dump+0x49c/0xed0
[   59.643529][ T2788]  ? __netlink_sendskb+0xc0/0xc0
[   59.644044][ T2788]  ? __netlink_dump_start+0x190/0x800
[   59.644617][ T2788]  ? __mutex_unlock_slowpath+0xd0/0x670
[   59.645177][ T2788]  __netlink_dump_start+0x5a0/0x800
[   59.645692][ T2788]  genl_rcv_msg+0xa75/0xe90
[   59.646144][ T2788]  ? __lock_acquire+0xdfe/0x3de0
[   59.646692][ T2788]  ? genl_family_rcv_msg_attrs_parse+0x320/0x320
[   59.647340][ T2788]  ? genl_lock_dumpit+0xb0/0xb0
[   59.647821][ T2788]  ? genl_unlock+0x20/0x20
[   59.648290][ T2788]  ? genl_parallel_done+0xe0/0xe0
[   59.648787][ T2788]  ? find_held_lock+0x39/0x1d0
[   59.649276][ T2788]  ? genl_rcv+0x15/0x40
[   59.649722][ T2788]  ? lock_contended+0xcd0/0xcd0
[   59.650296][ T2788]  netlink_rcv_skb+0x121/0x350
[   59.650828][ T2788]  ? genl_family_rcv_msg_attrs_parse+0x320/0x320
[   59.651491][ T2788]  ? netlink_ack+0x940/0x940
[   59.651953][ T2788]  ? lock_acquire+0x164/0x3b0
[   59.652449][ T2788]  genl_rcv+0x24/0x40
[   59.652841][ T2788]  netlink_unicast+0x421/0x600
[ ... ]

Fixes: 7e4369057806 ("tipc: fix a slab object leak")
Fixes: a62fbccecd62 ("tipc: make subscriber server support net namespace")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-21 10:47:35 +01:00
2019-12-17 20:39:57 +01:00
2019-12-17 20:39:59 +01:00
2019-12-17 20:39:21 +01:00
2019-12-17 20:40:05 +01:00

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

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

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.
Description
No description provided
Readme 5.7 GiB
Languages
C 97.6%
Assembly 1%
Shell 0.5%
Python 0.3%
Makefile 0.3%