KASAN: use-after-free Read in pn533_acr122_is_rx_frame_valid

Status: upstream: reported C repro on 2026/09/05 14:00
Subsystems: usb nfc
[Documentation on labels]
Reported-by: syzbot+1853daab1a47603d4678@syzkaller.appspotmail.com
First crash: 11h55m, last: 7h58m
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [usb?] [nfc?] KASAN: use-after-free Read in pn533_acr122_is_rx_frame_valid 0 (1) 2026/09/05 14:00

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in pn533_acr122_is_rx_frame_valid drivers/nfc/pn533/usb.c:325 [inline]
BUG: KASAN: use-after-free in pn533_acr122_is_rx_frame_valid+0x132/0x150 drivers/nfc/pn533/usb.c:315
Read of size 1 at addr ffff88816b5da3ce by task swapper/0/0

CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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
 pn533_acr122_is_rx_frame_valid drivers/nfc/pn533/usb.c:325 [inline]
 pn533_acr122_is_rx_frame_valid+0x132/0x150 drivers/nfc/pn533/usb.c:315
 pn533_recv_frame+0x1b7/0x6d0 drivers/nfc/pn533/pn533.c:2203
 __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+0xdb2/0x3700 drivers/usb/gadget/udc/dummy_hcd.c:2019
 __run_hrtimer kernel/time/hrtimer.c:2067 [inline]
 __hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2124
 hrtimer_run_softirq+0x1ca/0x360 kernel/time/hrtimer.c:2141
 handle_softirqs+0x1d9/0x9b0 kernel/softirq.c:645
 __do_softirq kernel/softirq.c:679 [inline]
 invoke_softirq kernel/softirq.c:519 [inline]
 __irq_exit_rcu+0x192/0x210 kernel/softirq.c:767
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:784
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x8f/0xb0 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:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: bf c3 01 e9 43 fa 02 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d e3 ff 1e 00 fb f4 <c3> cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff89607d00 EFLAGS: 00000242
RAX: 000000000009c36b RBX: ffffffff8962c940 RCX: ffffffff878789d5
RDX: 0000000000000001 RSI: ffffffff89327d4e RDI: ffffffff87d2a600
RBP: fffffbfff12c5928 R08: 0000000000000001 R09: ffffed103eac673d
R10: ffff8881f56339eb R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffffffff12c0fa4 R15: dffffc0000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
 default_idle+0x9/0x10 arch/x86/kernel/process.c:768
 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x3ae/0x5b0 kernel/sched/idle.c:355
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454
 rest_init+0x2d3/0x2e0 init/main.c:727
 start_kernel+0x489/0x490 init/main.c:1185
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x158
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x16b5da
flags: 0x200000000000000(node=0|zone=2)
raw: 0200000000000000 ffffea0005ad7688 ffffea0005ad7688 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner info is not present (never set?)

Memory state around the buggy address:
 ffff88816b5da280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88816b5da300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88816b5da380: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff88816b5da400: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88816b5da480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
----------------
Code disassembly (best guess):
   0:	bf c3 01 e9 43       	mov    $0x43e901c3,%edi
   5:	fa                   	cli
   6:	02 00                	add    (%rax),%al
   8:	0f 1f 00             	nopl   (%rax)
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	f3 0f 1e fa          	endbr64
  1f:	66 90                	xchg   %ax,%ax
  21:	0f 00 2d e3 ff 1e 00 	verw   0x1effe3(%rip)        # 0x1f000b
  28:	fb                   	sti
  29:	f4                   	hlt
* 2a:	c3                   	ret <-- trapping instruction
  2b:	cc                   	int3
  2c:	cc                   	int3
  2d:	cc                   	int3
  2e:	cc                   	int3
  2f:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
  36:	00 00 00
  39:	66 90                	xchg   %ax,%ax
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/05 09:13 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: use-after-free Read in pn533_acr122_is_rx_frame_valid
2026/09/05 08:15 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: use-after-free Read in pn533_acr122_is_rx_frame_valid
2026/09/05 07:09 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: use-after-free Read in pn533_acr122_is_rx_frame_valid
2026/09/05 06:08 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: use-after-free Read in pn533_acr122_is_rx_frame_valid
2026/09/05 05:16 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: use-after-free Read in pn533_acr122_is_rx_frame_valid
* Struck through repros no longer work on HEAD.