==================================================================
BUG: KASAN: slab-use-after-free in __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
BUG: KASAN: slab-use-after-free in _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
Read of size 1 at addr ffff888025927018 by task swapper/3/0
CPU: 3 UID: 0 PID: 0 Comm: swapper/3 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xcd/0x630 mm/kasan/report.c:482
kasan_report+0xe0/0x110 mm/kasan/report.c:595
__kasan_check_byte+0x36/0x50 mm/kasan/common.c:568
kasan_check_byte include/linux/kasan.h:399 [inline]
lock_acquire kernel/locking/lockdep.c:5842 [inline]
lock_acquire+0xfc/0x350 kernel/locking/lockdep.c:5825
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
p9_tag_remove net/9p/client.c:397 [inline]
p9_req_put net/9p/client.c:405 [inline]
p9_req_put+0xaf/0x250 net/9p/client.c:402
req_done+0x1dc/0x2e0 net/9p/trans_virtio.c:147
vring_interrupt drivers/virtio/virtio_ring.c:2719 [inline]
vring_interrupt+0x31b/0x400 drivers/virtio/virtio_ring.c:2694
__handle_irq_event_percpu+0x22c/0x7d0 kernel/irq/handle.c:158
handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210
handle_edge_irq+0x3ca/0x9e0 kernel/irq/chip.c:855
generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
handle_irq arch/x86/kernel/irq.c:254 [inline]
call_irq_handler arch/x86/kernel/irq.c:310 [inline]
__common_interrupt+0xcd/0x2f0 arch/x86/kernel/irq.c:325
common_interrupt+0x61/0xe0 arch/x86/kernel/irq.c:318
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
RIP: 0010:handle_softirqs+0x1dd/0x8e0 kernel/softirq.c:565
Code: 88 6c 24 26 4c 89 7c 24 18 48 c7 c7 20 a8 ab 8b e8 c8 e3 17 0a 65 66 c7 05 26 4f 5a 12 00 00 e8 69 44 47 00 fb bb ff ff ff ff <49> c7 c7 c0 c0 20 8e 41 0f bc dc 83 c3 01 0f 85 a4 00 00 00 e9 b1
RSP: 0018:ffffc900006f8f28 EFLAGS: 00000206
RAX: 00000000002a494e RBX: 00000000ffffffff RCX: ffffffff81c3747f
RDX: 0000000000000000 RSI: ffffffff8de513b8 RDI: ffffffff8c162b00
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90ab5c97 R11: 0000000000000000 R12: 0000000000000282
R13: 000000000000000a R14: 1ffff920000df1ed R15: ffffed1003bda000
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0x109/0x170 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 0c 62 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 53 03 16 00 fb f4 8c 09 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df8 EFLAGS: 00000282
RAX: 00000000002a494b RBX: 0000000000000003 RCX: ffffffff8b940c29
RDX: 0000000000000000 RSI: ffffffff8de513b8 RDI: ffffffff8c162b00
RBP: ffffed1003bda000 R08: 0000000000000001 R09: ffffed100d4e6655
R10: ffff88806a7332ab R11: 0000000000000000 R12: 0000000000000003
R13: ffff88801ded0000 R14: ffffffff90ab5c90 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:757
default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:190 [inline]
do_idle+0x391/0x510 kernel/sched/idle.c:330
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428
start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x148
Allocated by task 20948:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:405
kmalloc_noprof include/linux/slab.h:905 [inline]
p9_client_create+0xc7/0x11c0 net/9p/client.c:985
v9fs_session_init+0x1f7/0x1a80 fs/9p/v9fs.c:410
v9fs_mount+0xc5/0xa90 fs/9p/vfs_super.c:122
legacy_get_tree+0x10c/0x220 fs/fs_context.c:666
vfs_get_tree+0x8e/0x340 fs/super.c:1815
do_new_mount fs/namespace.c:3808 [inline]
path_mount+0x1513/0x2000 fs/namespace.c:4123
do_mount fs/namespace.c:4136 [inline]
__do_sys_mount fs/namespace.c:4347 [inline]
__se_sys_mount fs/namespace.c:4324 [inline]
__x64_sys_mount+0x28d/0x310 fs/namespace.c:4324
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 20948:
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:243 [inline]
__kasan_slab_free+0x60/0x70 mm/kasan/common.c:275
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2417 [inline]
slab_free mm/slub.c:4680 [inline]
kfree+0x2b4/0x4d0 mm/slub.c:4879
p9_client_create+0xa28/0x11c0 net/9p/client.c:1064
v9fs_session_init+0x1f7/0x1a80 fs/9p/v9fs.c:410
v9fs_mount+0xc5/0xa90 fs/9p/vfs_super.c:122
legacy_get_tree+0x10c/0x220 fs/fs_context.c:666
vfs_get_tree+0x8e/0x340 fs/super.c:1815
do_new_mount fs/namespace.c:3808 [inline]
path_mount+0x1513/0x2000 fs/namespace.c:4123
do_mount fs/namespace.c:4136 [inline]
__do_sys_mount fs/namespace.c:4347 [inline]
__se_sys_mount fs/namespace.c:4324 [inline]
__x64_sys_mount+0x28d/0x310 fs/namespace.c:4324
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff888025927000
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 24 bytes inside of
freed 512-byte region [ffff888025927000, ffff888025927200)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25924
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b842c80 ffffea0001789700 dead000000000003
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b842c80 ffffea0001789700 dead000000000003
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000964901 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 11201, tgid 11201 (syz-executor), ts 144614828769, free_ts 144544285258
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851
prep_new_page mm/page_alloc.c:1859 [inline]
get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858
__alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416
alloc_slab_page mm/slub.c:2487 [inline]
allocate_slab mm/slub.c:2655 [inline]
new_slab+0x247/0x330 mm/slub.c:2709
___slab_alloc+0xcf2/0x1740 mm/slub.c:3891
__slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3981
__slab_alloc_node mm/slub.c:4056 [inline]
slab_alloc_node mm/slub.c:4217 [inline]
__do_kmalloc_node mm/slub.c:4364 [inline]
__kmalloc_noprof+0x2f2/0x510 mm/slub.c:4377
kmalloc_noprof include/linux/slab.h:909 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155
ip6_route_info_create+0x14c/0x870 net/ipv6/route.c:3811
ip6_route_add.part.0+0x22/0x1d0 net/ipv6/route.c:3940
ip6_route_add+0x45/0x60 net/ipv6/route.c:3937
addrconf_add_mroute+0x1dd/0x350 net/ipv6/addrconf.c:2552
addrconf_add_dev+0x14e/0x1c0 net/ipv6/addrconf.c:2570
addrconf_dev_config net/ipv6/addrconf.c:3479 [inline]
addrconf_init_auto_addrs+0x201/0x810 net/ipv6/addrconf.c:3567
addrconf_notify+0xe93/0x19e0 net/ipv6/addrconf.c:3740
page last free pid 11273 tgid 11271 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
__free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895
device_release+0xa4/0x240 drivers/base/core.c:2565
kobject_cleanup lib/kobject.c:689 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x1e7/0x5a0 lib/kobject.c:737
netdev_run_todo+0x7e9/0x1320 net/core/dev.c:11513
tun_detach drivers/net/tun.c:640 [inline]
tun_chr_close+0xea/0x230 drivers/net/tun.c:3433
__fput+0x3ff/0xb70 fs/file_table.c:468
task_work_run+0x150/0x240 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xeb/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff888025926f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888025926f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888025927000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888025927080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888025927100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: 88 6c 24 26 mov %ch,0x26(%rsp)
4: 4c 89 7c 24 18 mov %r15,0x18(%rsp)
9: 48 c7 c7 20 a8 ab 8b mov $0xffffffff8baba820,%rdi
10: e8 c8 e3 17 0a call 0xa17e3dd
15: 65 66 c7 05 26 4f 5a movw $0x0,%gs:0x125a4f26(%rip) # 0x125a4f45
1c: 12 00 00
1f: e8 69 44 47 00 call 0x47448d
24: fb sti
25: bb ff ff ff ff mov $0xffffffff,%ebx
* 2a: 49 c7 c7 c0 c0 20 8e mov $0xffffffff8e20c0c0,%r15 <-- trapping instruction
31: 41 0f bc dc bsf %r12d,%ebx
35: 83 c3 01 add $0x1,%ebx
38: 0f 85 a4 00 00 00 jne 0xe2
3e: e9 .byte 0xe9
3f: b1 .byte 0xb1