KASAN: use-after-free Read in refcount_inc_not_zero

[upstream] KASAN: use-after-free Read in refcount_inc_not_zero_checked
Status: upstream: reported on 2019/01/02 10:35
Reported-by: syzbot+defa700d16f1bd1b9a05@syzkaller.appspotmail.com
First: 16d, last: 2d20h

Sample crash report:

team0 (unregistering): Port device team_slave_0 removed
bond0 (unregistering): Releasing backup interface bond_slave_1
bond0 (unregistering): Releasing backup interface bond_slave_0
bond0 (unregistering): Released all slaves
==================================================================
BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
BUG: KASAN: use-after-free in refcount_inc_not_zero_checked+0x91/0x2e0 lib/refcount.c:120
Read of size 4 at addr ffff888051174f00 by task syz-executor3/18447

CPU: 0 PID: 18447 Comm: syz-executor3 Not tainted 5.0.0-rc1+ #19
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+0x1db/0x2d0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x123/0x190 mm/kasan/generic.c:191
 kasan_check_read+0x11/0x20 mm/kasan/common.c:100
 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
 refcount_inc_not_zero_checked+0x91/0x2e0 lib/refcount.c:120
 refcount_inc_checked+0x17/0x70 lib/refcount.c:153
 sock_hold include/net/sock.h:647 [inline]
 nr_release+0x62/0x3c0 net/netrom/af_netrom.c:523
 __sock_release+0xd3/0x250 net/socket.c:579
 sock_close+0x1b/0x30 net/socket.c:1141
 __fput+0x3c5/0xb10 fs/file_table.c:278
 ____fput+0x16/0x20 fs/file_table.c:309
 task_work_run+0x1f4/0x2b0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x19d6/0x2650 kernel/exit.c:867
 do_group_exit+0x177/0x430 kernel/exit.c:970
 get_signal+0x8b4/0x19b0 kernel/signal.c:2517
 do_signal+0x91/0x1ea0 arch/x86/kernel/signal.c:816
 exit_to_usermode_loop+0x2f7/0x3b0 arch/x86/entry/common.c:162
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x696/0x800 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457ec9
Code: Bad RIP value.
RSP: 002b:00007f88cf927c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000457ec9
RDX: 0000000020000b00 RSI: 00000000000089a1 RDI: 0000000000000007
RBP: 000000000073c220 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f88cf9286d4
R13: 00000000004c31b1 R14: 00000000004d5a10 R15: 00000000ffffffff

Allocated by task 18410:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc mm/kasan/common.c:496 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:469
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:504
 __do_kmalloc mm/slab.c:3711 [inline]
 __kmalloc+0x15c/0x740 mm/slab.c:3720
 kmalloc include/linux/slab.h:550 [inline]
 sk_prot_alloc+0x19c/0x2e0 net/core/sock.c:1477
 sk_alloc+0xd7/0x1690 net/core/sock.c:1531
 nr_create+0xb9/0x5e0 net/netrom/af_netrom.c:436
 __sock_create+0x532/0x930 net/socket.c:1277
 sock_create net/socket.c:1317 [inline]
 __sys_socket+0x106/0x260 net/socket.c:1347
 __do_sys_socket net/socket.c:1356 [inline]
 __se_sys_socket net/socket.c:1354 [inline]
 __x64_sys_socket+0x73/0xb0 net/socket.c:1354
 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 0:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:458
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:466
 __cache_free mm/slab.c:3487 [inline]
 kfree+0xcf/0x230 mm/slab.c:3806
 sk_prot_free net/core/sock.c:1514 [inline]
 __sk_destruct+0x76d/0xa60 net/core/sock.c:1596
 sk_destruct+0x7b/0x90 net/core/sock.c:1604
 __sk_free+0xce/0x300 net/core/sock.c:1615
 sk_free+0x42/0x50 net/core/sock.c:1626
 sock_put include/net/sock.h:1707 [inline]
 nr_heartbeat_expiry+0x489/0x520 net/netrom/nr_timer.c:130
 call_timer_fn+0x254/0x900 kernel/time/timer.c:1325
 expire_timers kernel/time/timer.c:1362 [inline]
 __run_timers+0x6fc/0xd50 kernel/time/timer.c:1681
 run_timer_softirq+0x52/0xb0 kernel/time/timer.c:1694
 __do_softirq+0x30b/0xb11 kernel/softirq.c:292

The buggy address belongs to the object at ffff888051174e80
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 128 bytes inside of
 2048-byte region [ffff888051174e80, ffff888051175680)
The buggy address belongs to the page:
page:ffffea0001445d00 count:1 mapcount:0 mapping:ffff88812c3f0c40 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea0002a59208 ffffea00022d0808 ffff88812c3f0c40
raw: 0000000000000000 ffff888051174600 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888051174e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888051174e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888051174f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff888051174f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888051175000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

All crashes (11):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Maintainers
ci-upstream-kasan-gce-root	2019/01/11 16:36	upstream	1bdbe227	c3f3344c	.config	log	report	davem@davemloft.net, linux-hams@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, ralf@linux-mips.org
ci-upstream-kasan-gce-root	2019/01/05 19:03	upstream	3fed6ae4	53be0a37	.config	log	report	davem@davemloft.net, linux-hams@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, ralf@linux-mips.org
ci-upstream-kasan-gce-smack-root	2019/01/04 13:20	upstream	96d4f267	7da23925	.config	log	report	davem@davemloft.net, linux-hams@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, ralf@linux-mips.org
ci-upstream-kasan-gce-smack-root	2019/01/04 00:09	upstream	645ff1e8	7da23925	.config	log	report	davem@davemloft.net, linux-hams@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, ralf@linux-mips.org
ci-upstream-kasan-gce-root	2019/01/03 19:23	upstream	645ff1e8	66fcd29b	.config	log	report	davem@davemloft.net, linux-hams@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, ralf@linux-mips.org
ci-upstream-net-this-kasan-gce	2019/01/15 12:53	net	2f960bd0	ebacf5cb	.config	log	report	davem@davemloft.net, linux-hams@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, ralf@linux-mips.org
ci-upstream-net-this-kasan-gce	2019/01/13 10:39	net	8d008e64	c3f3344c	.config	log	report	davem@davemloft.net, linux-hams@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, ralf@linux-mips.org
ci-upstream-net-this-kasan-gce	2019/01/04 21:08	net	96d4f267	0127e3ba	.config	log	report	davem@davemloft.net, linux-hams@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, ralf@linux-mips.org
ci-upstream-net-kasan-gce	2019/01/03 22:19	net-next	b71acb0e	66fcd29b	.config	log	report	davem@davemloft.net, linux-hams@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, ralf@linux-mips.org
ci-upstream-linux-next-kasan-gce-root	2019/01/01 21:10	linux-next	6a1d2932	3d85f48c	.config	log	report	davem@davemloft.net, linux-hams@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, ralf@linux-mips.org
ci-upstream-linux-next-kasan-gce-root	2019/01/04 01:15	linux-next	a4983672	7da23925	.config	log	report	davem@davemloft.net, linux-hams@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, ralf@linux-mips.org