Hay
Date
July 17, 2025, 10:12 a.m.

Environment
qemu-arm64
qemu-x86_64

[   29.954379] ==================================================================
[   29.954515] BUG: KASAN: slab-use-after-free in rcu_uaf_reclaim+0x64/0x70
[   29.954587] Read of size 4 at addr fff00000c9ab5900 by task swapper/1/0
[   29.954634] 
[   29.954672] CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G    B            N  6.16.0-rc6-next-20250717 #1 PREEMPT 
[   29.954757] Tainted: [B]=BAD_PAGE, [N]=TEST
[   29.955049] Hardware name: linux,dummy-virt (DT)
[   29.955474] Call trace:
[   29.955557]  show_stack+0x20/0x38 (C)
[   29.956643]  dump_stack_lvl+0x8c/0xd0
[   29.956796]  print_report+0x118/0x5d0
[   29.956846]  kasan_report+0xdc/0x128
[   29.956898]  __asan_report_load4_noabort+0x20/0x30
[   29.956950]  rcu_uaf_reclaim+0x64/0x70
[   29.956995]  rcu_core+0x9f4/0x1e58
[   29.957043]  rcu_core_si+0x18/0x30
[   29.957100]  handle_softirqs+0x374/0xb28
[   29.957148]  __do_softirq+0x1c/0x28
[   29.957190]  ____do_softirq+0x18/0x30
[   29.957233]  call_on_irq_stack+0x24/0x30
[   29.957281]  do_softirq_own_stack+0x24/0x38
[   29.957326]  __irq_exit_rcu+0x1fc/0x318
[   29.957371]  irq_exit_rcu+0x1c/0x80
[   29.957415]  el1_interrupt+0x38/0x58
[   29.957460]  el1h_64_irq_handler+0x18/0x28
[   29.957506]  el1h_64_irq+0x6c/0x70
[   29.957606]  arch_local_irq_enable+0x4/0x8 (P)
[   29.957658]  do_idle+0x384/0x4e8
[   29.957703]  cpu_startup_entry+0x64/0x80
[   29.957749]  secondary_start_kernel+0x28c/0x340
[   29.957796]  __secondary_switched+0xc0/0xc8
[   29.957849] 
[   29.957868] Allocated by task 229:
[   29.961012]  kasan_save_stack+0x3c/0x68
[   29.961097]  kasan_save_track+0x20/0x40
[   29.961134]  kasan_save_alloc_info+0x40/0x58
[   29.961181]  __kasan_kmalloc+0xd4/0xd8
[   29.961216]  __kmalloc_cache_noprof+0x16c/0x3c0
[   29.961262]  rcu_uaf+0xb0/0x2d8
[   29.961300]  kunit_try_run_case+0x170/0x3f0
[   29.961343]  kunit_generic_run_threadfn_adapter+0x88/0x100
[   29.961386]  kthread+0x328/0x630
[   29.961421]  ret_from_fork+0x10/0x20
[   29.961456] 
[   29.961476] Freed by task 0:
[   29.961503]  kasan_save_stack+0x3c/0x68
[   29.961540]  kasan_save_track+0x20/0x40
[   29.961575]  kasan_save_free_info+0x4c/0x78
[   29.961611]  __kasan_slab_free+0x6c/0x98
[   29.961648]  kfree+0x214/0x3c8
[   29.961681]  rcu_uaf_reclaim+0x28/0x70
[   29.961719]  rcu_core+0x9f4/0x1e58
[   29.961753]  rcu_core_si+0x18/0x30
[   29.961788]  handle_softirqs+0x374/0xb28
[   29.961823]  __do_softirq+0x1c/0x28
[   29.961857] 
[   29.961891] Last potentially related work creation:
[   29.961924]  kasan_save_stack+0x3c/0x68
[   29.961963]  kasan_record_aux_stack+0xb4/0xc8
[   29.962000]  __call_rcu_common.constprop.0+0x74/0x8c8
[   29.962042]  call_rcu+0x18/0x30
[   29.963200]  rcu_uaf+0x14c/0x2d8
[   29.963447]  kunit_try_run_case+0x170/0x3f0
[   29.963604]  kunit_generic_run_threadfn_adapter+0x88/0x100
[   29.964125]  kthread+0x328/0x630
[   29.964168]  ret_from_fork+0x10/0x20
[   29.965016] 
[   29.965072] The buggy address belongs to the object at fff00000c9ab5900
[   29.965072]  which belongs to the cache kmalloc-32 of size 32
[   29.966014] The buggy address is located 0 bytes inside of
[   29.966014]  freed 32-byte region [fff00000c9ab5900, fff00000c9ab5920)
[   29.966439] 
[   29.966472] The buggy address belongs to the physical page:
[   29.966711] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x109ab5
[   29.967653] flags: 0xbfffe0000000000(node=0|zone=2|lastcpupid=0x1ffff)
[   29.967860] page_type: f5(slab)
[   29.968089] raw: 0bfffe0000000000 fff00000c0001780 dead000000000122 0000000000000000
[   29.968700] raw: 0000000000000000 0000000080400040 00000000f5000000 0000000000000000
[   29.968787] page dumped because: kasan: bad access detected
[   29.968819] 
[   29.969431] Memory state around the buggy address:
[   29.969632]  fff00000c9ab5800: 00 00 00 fc fc fc fc fc 00 00 05 fc fc fc fc fc
[   29.969680]  fff00000c9ab5880: 00 00 07 fc fc fc fc fc fa fb fb fb fc fc fc fc
[   29.970417] >fff00000c9ab5900: fa fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
[   29.970691]                    ^
[   29.971228]  fff00000c9ab5980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   29.971334]  fff00000c9ab5a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   29.971404] ==================================================================

[   26.203370] ==================================================================
[   26.204003] BUG: KASAN: slab-use-after-free in rcu_uaf_reclaim+0x50/0x60
[   26.204463] Read of size 4 at addr ffff888106000840 by task swapper/1/0
[   26.204783] 
[   26.204888] CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G    B            N  6.16.0-rc6-next-20250717 #1 PREEMPT(voluntary) 
[   26.204939] Tainted: [B]=BAD_PAGE, [N]=TEST
[   26.204951] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[   26.204971] Call Trace:
[   26.204999]  <IRQ>
[   26.205015]  dump_stack_lvl+0x73/0xb0
[   26.205045]  print_report+0xd1/0x610
[   26.205067]  ? __virt_addr_valid+0x1db/0x2d0
[   26.205105]  ? rcu_uaf_reclaim+0x50/0x60
[   26.205124]  ? kasan_complete_mode_report_info+0x64/0x200
[   26.205149]  ? rcu_uaf_reclaim+0x50/0x60
[   26.205169]  kasan_report+0x141/0x180
[   26.205191]  ? rcu_uaf_reclaim+0x50/0x60
[   26.205215]  __asan_report_load4_noabort+0x18/0x20
[   26.205238]  rcu_uaf_reclaim+0x50/0x60
[   26.205294]  rcu_core+0x66f/0x1c40
[   26.205324]  ? __pfx_rcu_core+0x10/0x10
[   26.205345]  ? ktime_get+0x6b/0x150
[   26.205370]  rcu_core_si+0x12/0x20
[   26.205389]  handle_softirqs+0x209/0x730
[   26.205409]  ? hrtimer_interrupt+0x2fe/0x780
[   26.205436]  ? __pfx_handle_softirqs+0x10/0x10
[   26.205460]  __irq_exit_rcu+0xc9/0x110
[   26.205479]  irq_exit_rcu+0x12/0x20
[   26.205498]  sysvec_apic_timer_interrupt+0x81/0x90
[   26.205522]  </IRQ>
[   26.205549]  <TASK>
[   26.205560]  asm_sysvec_apic_timer_interrupt+0x1f/0x30
[   26.205682] RIP: 0010:pv_native_safe_halt+0xf/0x20
[   26.205890] Code: 1f 84 00 00 00 00 00 0f 1f 40 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 83 f3 16 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
[   26.205977] RSP: 0000:ffff88810087fdc8 EFLAGS: 00010206
[   26.206090] RAX: ffff8881c3113000 RBX: ffff88810085b000 RCX: ffffffff95b1c985
[   26.206139] RDX: ffffed102b626193 RSI: 0000000000000004 RDI: 00000000000199f4
[   26.206182] RBP: ffff88810087fdd0 R08: 0000000000000001 R09: ffffed102b626192
[   26.206224] R10: ffff88815b130c93 R11: ffff88815b1363c8 R12: 0000000000000001
[   26.206317] R13: ffffed102010b600 R14: ffffffff977fadd0 R15: 0000000000000000
[   26.206380]  ? ct_kernel_exit.constprop.0+0xa5/0xd0
[   26.206435]  ? default_idle+0xd/0x20
[   26.206453]  arch_cpu_idle+0xd/0x20
[   26.206471]  default_idle_call+0x48/0x80
[   26.206489]  do_idle+0x379/0x4f0
[   26.206515]  ? __pfx_do_idle+0x10/0x10
[   26.206535]  ? _raw_spin_unlock_irqrestore+0x49/0x90
[   26.206557]  ? complete+0x15b/0x1d0
[   26.206583]  cpu_startup_entry+0x5c/0x70
[   26.206605]  start_secondary+0x211/0x290
[   26.206627]  ? __pfx_start_secondary+0x10/0x10
[   26.206653]  common_startup_64+0x13e/0x148
[   26.206686]  </TASK>
[   26.206696] 
[   26.221747] Allocated by task 247:
[   26.222018]  kasan_save_stack+0x45/0x70
[   26.222375]  kasan_save_track+0x18/0x40
[   26.222576]  kasan_save_alloc_info+0x3b/0x50
[   26.222772]  __kasan_kmalloc+0xb7/0xc0
[   26.222945]  __kmalloc_cache_noprof+0x189/0x420
[   26.223159]  rcu_uaf+0xb0/0x330
[   26.223301]  kunit_try_run_case+0x1a5/0x480
[   26.223922]  kunit_generic_run_threadfn_adapter+0x85/0xf0
[   26.224314]  kthread+0x337/0x6f0
[   26.224584]  ret_from_fork+0x116/0x1d0
[   26.224880]  ret_from_fork_asm+0x1a/0x30
[   26.225193] 
[   26.225387] Freed by task 0:
[   26.225696]  kasan_save_stack+0x45/0x70
[   26.225864]  kasan_save_track+0x18/0x40
[   26.226041]  kasan_save_free_info+0x3f/0x60
[   26.226241]  __kasan_slab_free+0x56/0x70
[   26.226720]  kfree+0x222/0x3f0
[   26.226838]  rcu_uaf_reclaim+0x1f/0x60
[   26.227217]  rcu_core+0x66f/0x1c40
[   26.227489]  rcu_core_si+0x12/0x20
[   26.227990]  handle_softirqs+0x209/0x730
[   26.228147]  __irq_exit_rcu+0xc9/0x110
[   26.228621]  irq_exit_rcu+0x12/0x20
[   26.228870]  sysvec_apic_timer_interrupt+0x81/0x90
[   26.229175]  asm_sysvec_apic_timer_interrupt+0x1f/0x30
[   26.229813] 
[   26.230142] Last potentially related work creation:
[   26.230749]  kasan_save_stack+0x45/0x70
[   26.231327]  kasan_record_aux_stack+0xb2/0xc0
[   26.231969]  __call_rcu_common.constprop.0+0x7b/0x9e0
[   26.232157]  call_rcu+0x12/0x20
[   26.232289]  rcu_uaf+0x168/0x330
[   26.232828]  kunit_try_run_case+0x1a5/0x480
[   26.233340]  kunit_generic_run_threadfn_adapter+0x85/0xf0
[   26.234011]  kthread+0x337/0x6f0
[   26.234187]  ret_from_fork+0x116/0x1d0
[   26.234636]  ret_from_fork_asm+0x1a/0x30
[   26.235017] 
[   26.235230] The buggy address belongs to the object at ffff888106000840
[   26.235230]  which belongs to the cache kmalloc-32 of size 32
[   26.236171] The buggy address is located 0 bytes inside of
[   26.236171]  freed 32-byte region [ffff888106000840, ffff888106000860)
[   26.236825] 
[   26.236898] The buggy address belongs to the physical page:
[   26.237060] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x106000
[   26.237620] flags: 0x200000000000000(node=0|zone=2)
[   26.238248] page_type: f5(slab)
[   26.238667] raw: 0200000000000000 ffff888100041780 dead000000000122 0000000000000000
[   26.239390] raw: 0000000000000000 0000000080400040 00000000f5000000 0000000000000000
[   26.240151] page dumped because: kasan: bad access detected
[   26.240800] 
[   26.240955] Memory state around the buggy address:
[   26.241368]  ffff888106000700: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
[   26.241892]  ffff888106000780: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
[   26.242129] >ffff888106000800: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
[   26.242374]                                            ^
[   26.242698]  ffff888106000880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   26.243050]  ffff888106000900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   26.243652] ==================================================================