mainlining shenanigans
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Ido Schimmel 471b83bd8b team: Forbid enslaving team device to itself
team's ndo_add_slave() acquires 'team->lock' and later tries to open the
newly enslaved device via dev_open(). This emits a 'NETDEV_UP' event
that causes the VLAN driver to add VLAN 0 on the team device. team's
ndo_vlan_rx_add_vid() will also try to acquire 'team->lock' and
deadlock.

Fix this by checking early at the enslavement function that a team
device is not being enslaved to itself.

A similar check was added to the bond driver in commit 09a89c219b
("bonding: disallow enslaving a bond to itself").

WARNING: possible recursive locking detected
4.18.0-rc7+ #176 Not tainted
--------------------------------------------
syz-executor4/6391 is trying to acquire lock:
(____ptrval____) (&team->lock){+.+.}, at: team_vlan_rx_add_vid+0x3b/0x1e0 drivers/net/team/team.c:1868

but task is already holding lock:
(____ptrval____) (&team->lock){+.+.}, at: team_add_slave+0xdb/0x1c30 drivers/net/team/team.c:1947

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&team->lock);
  lock(&team->lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by syz-executor4/6391:
 #0: (____ptrval____) (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: (____ptrval____) (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x412/0xc30 net/core/rtnetlink.c:4662
 #1: (____ptrval____) (&team->lock){+.+.}, at: team_add_slave+0xdb/0x1c30 drivers/net/team/team.c:1947

stack backtrace:
CPU: 1 PID: 6391 Comm: syz-executor4 Not tainted 4.18.0-rc7+ #176
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
 print_deadlock_bug kernel/locking/lockdep.c:1765 [inline]
 check_deadlock kernel/locking/lockdep.c:1809 [inline]
 validate_chain kernel/locking/lockdep.c:2405 [inline]
 __lock_acquire.cold.64+0x1fb/0x486 kernel/locking/lockdep.c:3435
 lock_acquire+0x1e4/0x540 kernel/locking/lockdep.c:3924
 __mutex_lock_common kernel/locking/mutex.c:757 [inline]
 __mutex_lock+0x176/0x1820 kernel/locking/mutex.c:894
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:909
 team_vlan_rx_add_vid+0x3b/0x1e0 drivers/net/team/team.c:1868
 vlan_add_rx_filter_info+0x14a/0x1d0 net/8021q/vlan_core.c:210
 __vlan_vid_add net/8021q/vlan_core.c:278 [inline]
 vlan_vid_add+0x63e/0x9d0 net/8021q/vlan_core.c:308
 vlan_device_event.cold.12+0x2a/0x2f net/8021q/vlan.c:381
 notifier_call_chain+0x180/0x390 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1735
 call_netdevice_notifiers net/core/dev.c:1753 [inline]
 dev_open+0x173/0x1b0 net/core/dev.c:1433
 team_port_add drivers/net/team/team.c:1219 [inline]
 team_add_slave+0xa8b/0x1c30 drivers/net/team/team.c:1948
 do_set_master+0x1c9/0x220 net/core/rtnetlink.c:2248
 do_setlink+0xba4/0x3e10 net/core/rtnetlink.c:2382
 rtnl_setlink+0x2a9/0x400 net/core/rtnetlink.c:2636
 rtnetlink_rcv_msg+0x46e/0xc30 net/core/rtnetlink.c:4665
 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2455
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4683
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x5a0/0x760 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0xa18/0xfd0 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:642 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:652
 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2126
 __sys_sendmsg+0x11d/0x290 net/socket.c:2164
 __do_sys_sendmsg net/socket.c:2173 [inline]
 __se_sys_sendmsg net/socket.c:2171 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2171
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x456b29
Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f9706bf8c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f9706bf96d4 RCX: 0000000000456b29
RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000004
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d3548 R14: 00000000004c8227 R15: 0000000000000000

Fixes: 87002b03ba ("net: introduce vlan_vid_[add/del] and use them instead of direct [add/kill]_vid ndo calls")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-and-tested-by: syzbot+bd051aba086537515cdb@syzkaller.appspotmail.com
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-04 13:55:40 -07:00
arch Late arm64 fixes 2018-10-01 17:24:20 -07:00
block blk-mq: I/O and timer unplugs are inverted in blktrace 2018-09-27 13:12:44 -06:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto DMAengine updates for v4.19-rc1 2018-08-18 15:55:59 -07:00
Documentation Merge gitolite.kernel.org:/pub/scm/linux/kernel/git/davem/net 2018-10-03 16:09:11 -07:00
drivers team: Forbid enslaving team device to itself 2018-10-04 13:55:40 -07:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-10-03 04:21:23 -07:00
include Merge gitolite.kernel.org:/pub/scm/linux/kernel/git/davem/net 2018-10-03 16:09:11 -07:00
init Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
ipc ipc/shm: properly return EIDRM in shm_lock() 2018-09-04 16:45:02 -07:00
kernel Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-09-29 11:32:03 -07:00
lib lib/Kconfig.debug: fix three typos in help text 2018-09-04 16:45:02 -07:00
LICENSES LICENSES: Add Linux-OpenIB license text 2018-04-27 16:41:53 -06:00
mm mm: slowly shrink slabs with a relatively small number of objects 2018-09-20 22:01:11 +02:00
net Just three small fixes: 2018-10-04 13:47:39 -07:00
samples samples/bpf: all XDP samples should unload xdp/bpf prog on SIGTERM 2018-08-16 21:55:32 +02:00
scripts linux-kselftest-4.19-rc5 2018-09-17 07:24:28 +02:00
security Revert "uapi/linux/keyctl.h: don't use C++ reserved keyword as a struct member name" 2018-09-25 13:28:58 +02:00
sound ASoC: Fixes for v4.19 2018-09-17 18:59:21 +02:00
tools linux-kselftest-4.19-rc7 2018-10-03 11:06:49 -07:00
usr initramfs: move gen_initramfs_list.sh from scripts/ to usr/ 2018-08-22 23:21:44 +09:00
virt KVM: Remove obsolete kvm_unmap_hva notifier backend 2018-09-07 15:06:02 +02:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS Merge gitolite.kernel.org:/pub/scm/linux/kernel/git/davem/net 2018-10-03 16:09:11 -07:00
Makefile Linux 4.19-rc6 2018-09-30 07:15:35 -07:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -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.
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.