Re: [syzbot] [usb?] KASAN: slab-out-of-bounds Read in usbtmc_interrupt

[syzbot <syzbot+abbfd103085885cf16a2@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-out-of-bounds Read in usbtmc_interrupt

usbtmc 1-1:16.0: invalid notification: 73
usbtmc 1-1:16.0: invalid notification: 33
usbtmc 1-1:16.0: invalid notification: 36
usbtmc 1-1:16.0: invalid notification: 8
==================================================================
BUG: KASAN: slab-out-of-bounds in usbtmc_interrupt+0x560/0x720 drivers/usb/class/usbtmc.c:2314
Read of size 1 at addr ffff8880328ca261 by task swapper/1/0

CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.17.0-rc1-next-20250815-syzkaller-g1357b2649c02-dirty #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 usbtmc_interrupt+0x560/0x720 drivers/usb/class/usbtmc.c:2314
 __usb_hcd_giveback_urb+0x376/0x540 drivers/usb/core/hcd.c:1661
 dummy_timer+0x862/0x4550 drivers/usb/gadget/udc/dummy_hcd.c:1995
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1842
 handle_softirqs+0x283/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 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+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: d3 e7 02 00 cc cc cc 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 33 ea 24 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6
RAX: 9a4dc4a4e698df00 RBX: ffffffff8196d418 RCX: 9a4dc4a4e698df00
RDX: 0000000000000001 RSI: ffffffff8c04da60 RDI: ffffffff8196d418
RBP: ffffc90000197f20 R08: ffff8880b8732f9b R09: 1ffff110170e65f3
R10: dffffc0000000000 R11: ffffed10170e65f4 R12: ffffffff8fe4e130
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11003ad8b40
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:757
 default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:190 [inline]
 do_idle+0x1e8/0x510 kernel/sched/idle.c:330
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
 common_startup_64+0x13e/0x147
 </TASK>

Allocated by task 921:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4365 [inline]
 __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4377
 kmalloc_noprof include/linux/slab.h:913 [inline]
 usbtmc_probe+0xa3a/0x1ad0 drivers/usb/class/usbtmc.c:2467
 usb_probe_interface+0x665/0xc30 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x26d/0x9e0 drivers/base/dd.c:659
 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801
 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831
 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959
 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462
 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031
 bus_probe_device+0x185/0x260 drivers/base/bus.c:537
 device_add+0x7b6/0xb50 drivers/base/core.c:3689
 usb_set_configuration+0x1a87/0x20e0 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
 usb_probe_device+0x1c4/0x390 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x26d/0x9e0 drivers/base/dd.c:659
 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:801
 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831
 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959
 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462
 __device_attach+0x2b8/0x400 drivers/base/dd.c:1031
 bus_probe_device+0x185/0x260 drivers/base/bus.c:537
 device_add+0x7b6/0xb50 drivers/base/core.c:3689
 usb_new_device+0xa39/0x16f0 drivers/usb/core/hub.c:2694
 hub_port_connect drivers/usb/core/hub.c:5566 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
 port_event drivers/usb/core/hub.c:5870 [inline]
 hub_event+0x2958/0x4a20 drivers/usb/core/hub.c:5952
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff8880328ca260
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes to the right of
 allocated 1-byte region [ffff8880328ca260, ffff8880328ca261)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x328ca
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801a841500 dead000000000100 dead000000000122
raw: 0000000000000000 0000000080800080 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5215, tgid 5215 (init), ts 19330584896, free_ts 18340276944
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
 prep_new_page mm/page_alloc.c:1859 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:2487 [inline]
 allocate_slab+0x8a/0x370 mm/slub.c:2655
 new_slab mm/slub.c:2709 [inline]
 ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891
 __slab_alloc mm/slub.c:3981 [inline]
 __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+0x305/0x4f0 mm/slub.c:4377
 kmalloc_noprof include/linux/slab.h:913 [inline]
 kzalloc_noprof include/linux/slab.h:1043 [inline]
 ima_write_template_field_data+0x47/0x490 security/integrity/ima/ima_template_lib.c:55
 ima_eventname_init_common+0x1e0/0x240 security/integrity/ima/ima_template_lib.c:522
 ima_alloc_init_template+0x30d/0x6f0 security/integrity/ima/ima_api.c:70
 ima_store_measurement+0x1b7/0x640 security/integrity/ima/ima_api.c:376
 process_measurement+0x11eb/0x1a40 security/integrity/ima/ima_main.c:413
 ima_bprm_check+0xfd/0x200 security/integrity/ima/ima_main.c:580
 security_bprm_check+0xd9/0x270 security/security.c:1341
 search_binary_handler fs/exec.c:1660 [inline]
 exec_binprm fs/exec.c:1702 [inline]
 bprm_execve+0x8ee/0x1450 fs/exec.c:1754
 do_execveat_common+0x510/0x6a0 fs/exec.c:1860
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
 kasan_depopulate_vmalloc_pte+0x74/0xa0 mm/kasan/shadow.c:472
 apply_to_pte_range mm/memory.c:3143 [inline]
 apply_to_pmd_range mm/memory.c:3187 [inline]
 apply_to_pud_range mm/memory.c:3223 [inline]
 apply_to_p4d_range mm/memory.c:3259 [inline]
 __apply_to_page_range+0xb92/0x1380 mm/memory.c:3295
 kasan_release_vmalloc+0xa2/0xd0 mm/kasan/shadow.c:593
 kasan_release_vmalloc_node mm/vmalloc.c:2249 [inline]
 purge_vmap_node+0x214/0x8f0 mm/vmalloc.c:2266
 __purge_vmap_area_lazy+0x7a4/0xb40 mm/vmalloc.c:2356
 _vm_unmap_aliases+0x70f/0x7b0 mm/vmalloc.c:2951
 change_page_attr_set_clr+0x305/0xeb0 arch/x86/mm/pat/set_memory.c:2088
 change_page_attr_set arch/x86/mm/pat/set_memory.c:2129 [inline]
 set_memory_nx+0xd6/0x110 arch/x86/mm/pat/set_memory.c:2318
 free_init_pages arch/x86/mm/init.c:933 [inline]
 free_kernel_image_pages+0x85/0x100 arch/x86/mm/init.c:952
 kernel_init+0x31/0x1d0 init/main.c:1490
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff8880328ca100: fa fc fc fc fa fc fc fc 06 fc fc fc 06 fc fc fc
 ffff8880328ca180: 00 fc fc fc fa fc fc fc fa fc fc fc 00 fc fc fc
>ffff8880328ca200: fa fc fc fc 00 fc fc fc fa fc fc fc 01 fc fc fc
                                                       ^
 ffff8880328ca280: fa fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc
 ffff8880328ca300: fa fc fc fc fa fc fc fc 04 fc fc fc fa fc fc fc
==================================================================
----------------
Code disassembly (best guess):
   0:	d3 e7                	shl    %cl,%edi
   2:	02 00                	add    (%rax),%al
   4:	cc                   	int3
   5:	cc                   	int3
   6:	cc                   	int3
   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:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	f3 0f 1e fa          	endbr64
  1b:	66 90                	xchg   %ax,%ax
  1d:	0f 00 2d 33 ea 24 00 	verw   0x24ea33(%rip)        # 0x24ea57
  24:	f3 0f 1e fa          	endbr64
  28:	fb                   	sti
  29:	f4                   	hlt
* 2a:	c3                   	ret <-- trapping instruction
  2b:	cc                   	int3
  2c:	cc                   	int3
  2d:	cc                   	int3
  2e:	cc                   	int3
  2f:	cc                   	int3
  30:	cc                   	int3
  31:	cc                   	int3
  32:	cc                   	int3
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	cc                   	int3
  37:	90                   	nop
  38:	90                   	nop
  39:	90                   	nop
  3a:	90                   	nop
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop


Tested on:

commit:         1357b264 Add linux-next specific files for 20250815
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=12aa73a2580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=6401f805169ac8b0
dashboard link: https://syzkaller.appspot.com/bug?extid=abbfd103085885cf16a2
compiler:       Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
patch:          https://syzkaller.appspot.com/x/patch.diff?x=10a2e234580000