==================================================================
BUG: KASAN: slab-use-after-free in __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
BUG: KASAN: slab-use-after-free in _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:166
Read of size 1 at addr ffff88802aee3818 by task swapper/3/0
CPU: 3 UID: 0 PID: 0 Comm: swapper/3 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x13d/0x4b0 mm/kasan/report.c:482
kasan_report+0xdf/0x1d0 mm/kasan/report.c:595
__kasan_check_byte+0x36/0x50 mm/kasan/common.c:574
kasan_check_byte include/linux/kasan.h:402 [inline]
lock_acquire kernel/locking/lockdep.c:5842 [inline]
lock_acquire+0x12a/0x370 kernel/locking/lockdep.c:5825
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:166
p9_tag_remove net/9p/client.c:274 [inline]
p9_req_put net/9p/client.c:282 [inline]
p9_req_put+0xaf/0x250 net/9p/client.c:279
req_done+0x1dc/0x2e0 net/9p/trans_virtio.c:147
vring_interrupt+0x2ef/0x650 drivers/virtio/virtio_ring.c:3254
__handle_irq_event_percpu+0x235/0x8c0 kernel/irq/handle.c:209
handle_irq_event_percpu kernel/irq/handle.c:246 [inline]
handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:263
handle_edge_irq+0x35e/0x960 kernel/irq/chip.c:857
generic_handle_irq_desc include/linux/irqdesc.h:186 [inline]
handle_irq arch/x86/kernel/irq.c:262 [inline]
call_irq_handler arch/x86/kernel/irq.c:318 [inline]
__common_interrupt+0xd8/0x2f0 arch/x86/kernel/irq.c:333
common_interrupt+0x60/0xe0 arch/x86/kernel/irq.c:326
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
RIP: 0010:handle_softirqs+0x1ad/0xa00 kernel/softirq.c:608
Code: 30 44 88 74 24 23 45 89 ee 48 c7 c7 00 77 ad 8b e8 98 fb c2 09 31 d2 65 66 89 15 96 22 43 12 e8 d9 b6 48 00 fb bb ff ff ff ff <49> c7 c4 c0 a0 40 8e 41 0f bc de 83 c3 01 0f 85 a4 00 00 00 e9 47
RSP: 0018:ffffc900006f8f20 EFLAGS: 00000202
RAX: 0000000000089264 RBX: 00000000ffffffff RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8df23e29 RDI: ffffffff8c1c4180
RBP: 00000000ffffe0ae R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 000000000000000a
R13: 0000000000000280 R14: 0000000000000280 R15: 1ffff920000df1ec
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 66 92 02 e9 c3 42 03 00 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 63 61 20 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df0 EFLAGS: 00000206
RAX: 000000000008925f RBX: ffff88801ead2500 RCX: ffffffff8b8b3095
RDX: 0000000000000000 RSI: ffffffff8df23e29 RDI: ffffffff8c1c4180
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed100d4e67b5
R10: ffff88806a733dab R11: 0000000000000000 R12: 0000000000000003
R13: ffffed1003d5a4a0 R14: 0000000000000003 R15: ffffffff90d7e150
arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:767
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x464/0x590 kernel/sched/idle.c:352
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:451
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x148
Allocated by task 8404:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kmalloc_noprof include/linux/slab.h:950 [inline]
p9_client_create+0xaf/0xd40 net/9p/client.c:862
v9fs_session_init+0x3c/0xd20 fs/9p/v9fs.c:446
v9fs_get_tree+0xb8/0xb50 fs/9p/vfs_super.c:97
vfs_get_tree+0x92/0x320 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3758 [inline]
do_new_mount fs/namespace.c:3834 [inline]
path_mount+0x7d0/0x23d0 fs/namespace.c:4154
do_mount fs/namespace.c:4167 [inline]
__do_sys_mount fs/namespace.c:4383 [inline]
__se_sys_mount fs/namespace.c:4360 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4360
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 8404:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2689 [inline]
slab_free mm/slub.c:6251 [inline]
kfree+0x223/0x6c0 mm/slub.c:6566
p9_client_create+0x72d/0xd40 net/9p/client.c:941
v9fs_session_init+0x3c/0xd20 fs/9p/v9fs.c:446
v9fs_get_tree+0xb8/0xb50 fs/9p/vfs_super.c:97
vfs_get_tree+0x92/0x320 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3758 [inline]
do_new_mount fs/namespace.c:3834 [inline]
path_mount+0x7d0/0x23d0 fs/namespace.c:4154
do_mount fs/namespace.c:4167 [inline]
__do_sys_mount fs/namespace.c:4383 [inline]
__se_sys_mount fs/namespace.c:4360 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4360
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88802aee3800
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 24 bytes inside of
freed 512-byte region [ffff88802aee3800, ffff88802aee3a00)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2aee0
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b842c80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b842c80 dead000000000100 dead000000000122
head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffffffffffff01 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 5757, tgid 5757 (syz-executor), ts 131531851149, free_ts 131067291490
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1858
prep_new_page mm/page_alloc.c:1866 [inline]
get_page_from_freelist+0x11a6/0x33b0 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x27c/0x2bc0 mm/page_alloc.c:5226
alloc_slab_page mm/slub.c:3278 [inline]
allocate_slab mm/slub.c:3467 [inline]
new_slab+0xa6/0x6c0 mm/slub.c:3525
refill_objects+0x277/0x420 mm/slub.c:7272
refill_sheaf mm/slub.c:2816 [inline]
__pcs_replace_empty_main+0x375/0x650 mm/slub.c:4652
alloc_from_pcs mm/slub.c:4750 [inline]
slab_alloc_node mm/slub.c:4884 [inline]
__do_kmalloc_node mm/slub.c:5295 [inline]
__kmalloc_noprof+0x688/0x850 mm/slub.c:5308
kmalloc_noprof include/linux/slab.h:954 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155
ip6_route_info_create+0x14c/0xad0 net/ipv6/route.c:3828
ip6_route_add+0x4b/0x1d0 net/ipv6/route.c:3957
addrconf_prefix_route+0x2fb/0x510 net/ipv6/addrconf.c:2488
fixup_permanent_addr net/ipv6/addrconf.c:3603 [inline]
addrconf_permanent_addr net/ipv6/addrconf.c:3639 [inline]
addrconf_notify+0x1548/0x1ba0 net/ipv6/addrconf.c:3706
notifier_call_chain+0x99/0x400 kernel/notifier.c:85
call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2249
call_netdevice_notifiers_extack net/core/dev.c:2287 [inline]
call_netdevice_notifiers net/core/dev.c:2301 [inline]
__dev_notify_flags+0x12c/0x2e0 net/core/dev.c:9797
netif_change_flags+0x108/0x160 net/core/dev.c:9826
page last free pid 5836 tgid 5836 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1402 [inline]
__free_frozen_pages+0x747/0x1040 mm/page_alloc.c:2943
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4570 [inline]
slab_alloc_node mm/slub.c:4899 [inline]
__do_kmalloc_node mm/slub.c:5295 [inline]
__kmalloc_node_track_caller_noprof+0x2ba/0x850 mm/slub.c:5408
kmalloc_reserve+0xe8/0x350 net/core/skbuff.c:635
__alloc_skb+0x185/0x710 net/core/skbuff.c:713
alloc_skb include/linux/skbuff.h:1383 [inline]
mld_newpack.isra.0+0x18e/0xa20 net/ipv6/mcast.c:1775
add_grhead+0x299/0x340 net/ipv6/mcast.c:1886
add_grec+0x1380/0x1920 net/ipv6/mcast.c:2025
mld_send_cr net/ipv6/mcast.c:2148 [inline]
mld_ifc_work+0x3c5/0xc10 net/ipv6/mcast.c:2693
process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314
process_scheduled_works kernel/workqueue.c:3397 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Memory state around the buggy address:
ffff88802aee3700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88802aee3780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802aee3800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88802aee3880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88802aee3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: 30 44 88 74 xor %al,0x74(%rax,%rcx,4)
4: 24 23 and $0x23,%al
6: 45 89 ee mov %r13d,%r14d
9: 48 c7 c7 00 77 ad 8b mov $0xffffffff8bad7700,%rdi
10: e8 98 fb c2 09 call 0x9c2fbad
15: 31 d2 xor %edx,%edx
17: 65 66 89 15 96 22 43 mov %dx,%gs:0x12432296(%rip) # 0x124322b5
1e: 12
1f: e8 d9 b6 48 00 call 0x48b6fd
24: fb sti
25: bb ff ff ff ff mov $0xffffffff,%ebx
* 2a: 49 c7 c4 c0 a0 40 8e mov $0xffffffff8e40a0c0,%r12 <-- trapping instruction
31: 41 0f bc de bsf %r14d,%ebx
35: 83 c3 01 add $0x1,%ebx
38: 0f 85 a4 00 00 00 jne 0xe2
3e: e9 .byte 0xe9
3f: 47 rex.RXB