Taehee Yoo ad9bd8daf2 bonding: fix using uninitialized mode_lock
When a bonding interface is being created, it setups its mode and options.
At that moment, it uses mode_lock so mode_lock should be initialized
before that moment.

rtnl_newlink()
	rtnl_create_link()
		alloc_netdev_mqs()
			->setup() //bond_setup()
	->newlink //bond_newlink
		bond_changelink()
		register_netdevice()
			->ndo_init() //bond_init()

After commit 089bca2cae ("bonding: use dynamic lockdep key instead of
subclass"), mode_lock is initialized in bond_init().
So in the bond_changelink(), un-initialized mode_lock can be used.
mode_lock should be initialized in bond_setup().
This patch partially reverts commit 089bca2cae ("bonding: use dynamic
lockdep key instead of subclass")

Test command:
    ip link add bond0 type bond mode 802.3ad lacp_rate 0

Splat looks like:
[   60.615127] INFO: trying to register non-static key.
[   60.615900] the code is fine but needs lockdep annotation.
[   60.616697] turning off the locking correctness validator.
[   60.617490] CPU: 1 PID: 957 Comm: ip Not tainted 5.4.0-rc3+ #109
[   60.618350] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   60.619481] Call Trace:
[   60.619918]  dump_stack+0x7c/0xbb
[   60.620453]  register_lock_class+0x1215/0x14d0
[   60.621131]  ? alloc_netdev_mqs+0x7b3/0xcc0
[   60.621771]  ? is_bpf_text_address+0x86/0xf0
[   60.622416]  ? is_dynamic_key+0x230/0x230
[   60.623032]  ? unwind_get_return_address+0x5f/0xa0
[   60.623757]  ? create_prof_cpu_mask+0x20/0x20
[   60.624408]  ? arch_stack_walk+0x83/0xb0
[   60.625023]  __lock_acquire+0xd8/0x3de0
[   60.625616]  ? stack_trace_save+0x82/0xb0
[   60.626225]  ? stack_trace_consume_entry+0x160/0x160
[   60.626957]  ? deactivate_slab.isra.80+0x2c5/0x800
[   60.627668]  ? register_lock_class+0x14d0/0x14d0
[   60.628380]  ? alloc_netdev_mqs+0x7b3/0xcc0
[   60.629020]  ? save_stack+0x69/0x80
[   60.629574]  ? save_stack+0x19/0x80
[   60.630121]  ? __kasan_kmalloc.constprop.4+0xa0/0xd0
[   60.630859]  ? __kmalloc_node+0x16f/0x480
[   60.631472]  ? alloc_netdev_mqs+0x7b3/0xcc0
[   60.632121]  ? rtnl_create_link+0x2ed/0xad0
[   60.634388]  ? __rtnl_newlink+0xad4/0x11b0
[   60.635024]  lock_acquire+0x164/0x3b0
[   60.635608]  ? bond_3ad_update_lacp_rate+0x91/0x200 [bonding]
[   60.636463]  _raw_spin_lock_bh+0x38/0x70
[   60.637084]  ? bond_3ad_update_lacp_rate+0x91/0x200 [bonding]
[   60.637930]  bond_3ad_update_lacp_rate+0x91/0x200 [bonding]
[   60.638753]  ? bond_3ad_lacpdu_recv+0xb30/0xb30 [bonding]
[   60.639552]  ? bond_opt_get_val+0x180/0x180 [bonding]
[   60.640307]  ? ___slab_alloc+0x5aa/0x610
[   60.640925]  bond_option_lacp_rate_set+0x71/0x140 [bonding]
[   60.641751]  __bond_opt_set+0x1ff/0xbb0 [bonding]
[   60.643217]  ? kasan_unpoison_shadow+0x30/0x40
[   60.643924]  bond_changelink+0x9a4/0x1700 [bonding]
[   60.644653]  ? memset+0x1f/0x40
[   60.742941]  ? bond_slave_changelink+0x1a0/0x1a0 [bonding]
[   60.752694]  ? alloc_netdev_mqs+0x8ea/0xcc0
[   60.753330]  ? rtnl_create_link+0x2ed/0xad0
[   60.753964]  bond_newlink+0x1e/0x60 [bonding]
[   60.754612]  __rtnl_newlink+0xb9f/0x11b0
[ ... ]

Reported-by: syzbot+8da67f407bcba2c72e6e@syzkaller.appspotmail.com
Reported-by: syzbot+0d083911ab18b710da71@syzkaller.appspotmail.com
Fixes: 089bca2cae ("bonding: use dynamic lockdep key instead of subclass")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-29 18:03:36 -07:00
2019-10-13 16:37:36 -07:00

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.
Description
No description provided
Readme 7.9 GiB
Languages
C 97.7%
Assembly 1.6%
Makefile 0.3%
Perl 0.1%