syzbot
KASAN: slab-out-of-bounds Read in pn533_recv_frame
Status:
upstream: reported on 2026/10/12 17:44
Subsystems:
nfc
Labels:
prio:high
[Documentation on labels]
Reported-by: syzbot+93f169a8e7d66864f800@syzkaller.appspotmail.com
First crash: 4d12h, last: 5h03m
Sample crash report:
PN533 RX: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PN533 RX: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PN533 RX: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
PN533 RX: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
BUG: KASAN: slab-out-of-bounds in hex_dump_to_buffer+0xbc4/0xc60 lib/hexdump.c:194
Read of size 1 at addr ffff88804551ba00 by task syz.0.691/10352
CPU: 0 UID: 0 PID: 10352 Comm: syz.0.691 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
<IRQ>
__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/0x1c0 mm/kasan/report.c:595
hex_dump_to_buffer+0xbc4/0xc60 lib/hexdump.c:194
print_hex_dump+0x14a/0x1f0 lib/hexdump.c:277
pn533_recv_frame+0x48e/0x6d0 drivers/nfc/pn533/pn533.c:2202
__usb_hcd_giveback_urb+0x38e/0x610 drivers/usb/core/hcd.c:1657
usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741
dummy_timer+0xdaf/0x3820 drivers/usb/gadget/udc/dummy_hcd.c:2023
__run_hrtimer kernel/time/hrtimer.c:2074 [inline]
__hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2131
hrtimer_run_softirq+0x1ca/0x360 kernel/time/hrtimer.c:2148
handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0x16a/0x210 kernel/softirq.c:758
irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:filter_irq_stacks+0x19/0x90 kernel/stacktrace.c:397
Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 85 f6 74 61 53 31 c0 48 bb 00 00 00 00 00 fc ff df 48 83 ec 10 <48> 89 fa 48 c1 ea 03 80 3c 1a 00 75 4a 48 8b 17 48 81 fa 30 02 00
RSP: 0018:ffffc9000416f820 EFLAGS: 00000206
RAX: 0000000000000005 RBX: dffffc0000000000 RCX: 0000000000000001
RDX: ffffffff8274594b RSI: 000000000000000f RDI: ffffc9000416f8c0
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffc9000416f898
R13: ffffffff84dfe5d7 R14: 0000000001422008 R15: ffffea0000d96540
stack_depot_save_flags+0x27/0x9f0 lib/stackdepot.c:667
kasan_save_stack+0x3f/0x50 mm/kasan/common.c:58
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:264 [inline]
__kasan_slab_free+0x5f/0x80 mm/kasan/common.c:296
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2748 [inline]
slab_free mm/slub.c:6509 [inline]
kfree+0x22b/0x6d0 mm/slub.c:6802
selinux_release_secctx security/selinux/hooks.c:7111 [inline]
selinux_release_secctx+0x87/0x110 security/selinux/hooks.c:7108
security_release_secctx+0x7c/0x120 security/security.c:3992
audit_log_subj_ctx+0x3a9/0x450 kernel/audit.c:2324
audit_log_task_context+0x7f/0xb0 kernel/audit.c:2367
audit_log_task+0x1b7/0x3a0 kernel/auditsc.c:2902
audit_seccomp+0x7a/0x1f0 kernel/auditsc.c:2952
seccomp_log kernel/seccomp.c:1048 [inline]
__seccomp_filter+0x88c/0x1130 kernel/seccomp.c:1342
__seccomp_permit_syscall+0x224/0x2e0 kernel/seccomp.c:1402
syscall_trace_enter include/linux/entry-common.h:98 [inline]
syscall_enter_from_user_mode_work include/linux/entry-common.h:147 [inline]
do_syscall_64+0x591/0x790 arch/x86/entry/syscall_64.c:81
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f219af5ea0e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007f219bebaf38 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 00007f219bebc6c0 RCX: 00007f219af5ea0e
RDX: 00007f219bebaf90 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000000c0
R13: 0000000000000000 R14: 00007f219b225fa0 R15: 00007ffc2e7b6028
</TASK>
Allocated by task 10352:
kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:351 [inline]
__kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:377
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4683 [inline]
slab_alloc_node mm/slub.c:4996 [inline]
kmem_cache_alloc_node_noprof+0x282/0x6e0 mm/slub.c:5068
kmalloc_reserve+0x148/0x350 net/core/skbuff.c:615
__alloc_skb+0x185/0x710 net/core/skbuff.c:715
alloc_skb include/linux/skbuff.h:1384 [inline]
pn533_recv_response+0x100/0x200 drivers/nfc/pn533/usb.c:65
__usb_hcd_giveback_urb+0x38e/0x610 drivers/usb/core/hcd.c:1657
usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741
dummy_timer+0xdaf/0x3820 drivers/usb/gadget/udc/dummy_hcd.c:2023
__run_hrtimer kernel/time/hrtimer.c:2074 [inline]
__hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2131
hrtimer_run_softirq+0x1ca/0x360 kernel/time/hrtimer.c:2148
handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0x16a/0x210 kernel/softirq.c:758
irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
The buggy address belongs to the object at ffff88804551b740
which belongs to the cache skbuff_small_head of size 704
The buggy address is located 0 bytes to the right of
allocated 704-byte region [ffff88804551b740, ffff88804551ba00)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x45518
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 ffff88814040b780 dead000000000100 dead000000000122
raw: 0000000000000000 0000000200130013 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88814040b780 dead000000000100 dead000000000122
head: 0000000000000000 0000000200130013 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 1108, tgid 1108 (kworker/u8:8), ts 286234767687
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
prep_new_page mm/page_alloc.c:1879 [inline]
get_page_from_freelist+0x110d/0x35d0 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
alloc_slab_page mm/slub.c:3347 [inline]
allocate_slab mm/slub.c:3462 [inline]
new_slab+0xa9/0x6e0 mm/slub.c:3513
refill_objects+0xe3/0x410 mm/slub.c:7418
refill_sheaf mm/slub.c:2885 [inline]
__pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774
alloc_from_pcs mm/slub.c:4850 [inline]
slab_alloc_node mm/slub.c:4984 [inline]
kmem_cache_alloc_node_noprof+0x4f2/0x6e0 mm/slub.c:5068
kmalloc_reserve+0x148/0x350 net/core/skbuff.c:615
__alloc_skb+0x185/0x710 net/core/skbuff.c:715
alloc_skb include/linux/skbuff.h:1384 [inline]
nlmsg_new include/net/netlink.h:1055 [inline]
inet6_ifmcaddr_notify+0xd6/0x1d0 net/ipv6/mcast.c:928
__ipv6_dev_mc_inc+0x731/0xc80 net/ipv6/mcast.c:993
addrconf_join_solict net/ipv6/addrconf.c:2262 [inline]
addrconf_dad_begin net/ipv6/addrconf.c:4135 [inline]
addrconf_dad_work+0x276/0x1360 net/ipv6/addrconf.c:4263
process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
process_scheduled_works kernel/workqueue.c:3479 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
page last free pid 4956 tgid 4956 ts 286222916440 stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
__free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
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:361
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4683 [inline]
slab_alloc_node mm/slub.c:4996 [inline]
kmem_cache_alloc_node_noprof+0x282/0x6e0 mm/slub.c:5068
__alloc_skb+0x140/0x710 net/core/skbuff.c:704
alloc_skb include/linux/skbuff.h:1384 [inline]
alloc_skb_with_frags+0xdd/0x760 net/core/skbuff.c:6803
sock_alloc_send_pskb+0x801/0x980 net/core/sock.c:3022
unix_dgram_sendmsg+0x3c7/0x1810 net/unix/af_unix.c:2144
sock_sendmsg_nosec net/socket.c:800 [inline]
__sock_sendmsg net/socket.c:815 [inline]
__sys_sendto+0x48b/0x4e0 net/socket.c:2281
__do_sys_sendto net/socket.c:2288 [inline]
__se_sys_sendto net/socket.c:2284 [inline]
__x64_sys_sendto+0xe0/0x1c0 net/socket.c:2284
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88804551b900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88804551b980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804551ba00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff88804551ba80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88804551bb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: 90 nop
1: 90 nop
2: 90 nop
3: 90 nop
4: 90 nop
5: 90 nop
6: 90 nop
7: 90 nop
8: 90 nop
9: 90 nop
a: 90 nop
b: 90 nop
c: 90 nop
d: 90 nop
e: 90 nop
f: 90 nop
10: 90 nop
11: f3 0f 1e fa endbr64
15: 85 f6 test %esi,%esi
17: 74 61 je 0x7a
19: 53 push %rbx
1a: 31 c0 xor %eax,%eax
1c: 48 bb 00 00 00 00 00 movabs $0xdffffc0000000000,%rbx
23: fc ff df
26: 48 83 ec 10 sub $0x10,%rsp
* 2a: 48 89 fa mov %rdi,%rdx <-- trapping instruction
2d: 48 c1 ea 03 shr $0x3,%rdx
31: 80 3c 1a 00 cmpb $0x0,(%rdx,%rbx,1)
35: 75 4a jne 0x81
37: 48 8b 17 mov (%rdi),%rdx
3a: 48 rex.W
3b: 81 .byte 0x81
3c: fa cli
3d: 30 02 xor %al,(%rdx)
Struck through repros no longer work on HEAD.