Hay
Date
July 8, 2025, 4:38 p.m.

Environment
qemu-arm64
qemu-x86_64

[   17.843969] ==================================================================
[   17.844023] BUG: KASAN: slab-use-after-free in kmalloc_uaf_16+0x3bc/0x438
[   17.844074] Read of size 16 at addr fff00000c5cff6e0 by task kunit_try_catch/170
[   17.844122] 
[   17.844161] CPU: 1 UID: 0 PID: 170 Comm: kunit_try_catch Tainted: G    B            N  6.15.6-rc1 #1 PREEMPT 
[   17.844318] Tainted: [B]=BAD_PAGE, [N]=TEST
[   17.844357] Hardware name: linux,dummy-virt (DT)
[   17.844387] Call trace:
[   17.844500]  show_stack+0x20/0x38 (C)
[   17.844596]  dump_stack_lvl+0x8c/0xd0
[   17.844914]  print_report+0x118/0x608
[   17.844962]  kasan_report+0xdc/0x128
[   17.845007]  __asan_report_load16_noabort+0x20/0x30
[   17.845059]  kmalloc_uaf_16+0x3bc/0x438
[   17.845106]  kunit_try_run_case+0x170/0x3f0
[   17.845450]  kunit_generic_run_threadfn_adapter+0x88/0x100
[   17.845560]  kthread+0x328/0x630
[   17.845767]  ret_from_fork+0x10/0x20
[   17.845821] 
[   17.845952] Allocated by task 170:
[   17.845981]  kasan_save_stack+0x3c/0x68
[   17.846068]  kasan_save_track+0x20/0x40
[   17.846472]  kasan_save_alloc_info+0x40/0x58
[   17.846522]  __kasan_kmalloc+0xd4/0xd8
[   17.846559]  __kmalloc_cache_noprof+0x16c/0x3c0
[   17.846608]  kmalloc_uaf_16+0x140/0x438
[   17.846745]  kunit_try_run_case+0x170/0x3f0
[   17.846783]  kunit_generic_run_threadfn_adapter+0x88/0x100
[   17.846825]  kthread+0x328/0x630
[   17.846892]  ret_from_fork+0x10/0x20
[   17.846927] 
[   17.846946] Freed by task 170:
[   17.847028]  kasan_save_stack+0x3c/0x68
[   17.847065]  kasan_save_track+0x20/0x40
[   17.847099]  kasan_save_free_info+0x4c/0x78
[   17.847136]  __kasan_slab_free+0x6c/0x98
[   17.847171]  kfree+0x214/0x3c8
[   17.847202]  kmalloc_uaf_16+0x190/0x438
[   17.847239]  kunit_try_run_case+0x170/0x3f0
[   17.847276]  kunit_generic_run_threadfn_adapter+0x88/0x100
[   17.847318]  kthread+0x328/0x630
[   17.847365]  ret_from_fork+0x10/0x20
[   17.847740] 
[   17.847798] The buggy address belongs to the object at fff00000c5cff6e0
[   17.847798]  which belongs to the cache kmalloc-16 of size 16
[   17.847855] The buggy address is located 0 bytes inside of
[   17.847855]  freed 16-byte region [fff00000c5cff6e0, fff00000c5cff6f0)
[   17.847913] 
[   17.847933] The buggy address belongs to the physical page:
[   17.847968] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x105cff
[   17.848194] flags: 0xbfffe0000000000(node=0|zone=2|lastcpupid=0x1ffff)
[   17.848270] page_type: f5(slab)
[   17.848358] raw: 0bfffe0000000000 fff00000c0001640 dead000000000122 0000000000000000
[   17.848555] raw: 0000000000000000 0000000080800080 00000000f5000000 0000000000000000
[   17.849155] page dumped because: kasan: bad access detected
[   17.849198] 
[   17.849230] Memory state around the buggy address:
[   17.849263]  fff00000c5cff580: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc
[   17.849327]  fff00000c5cff600: 00 00 fc fc fa fb fc fc fa fb fc fc fa fb fc fc
[   17.849380] >fff00000c5cff680: fa fb fc fc fa fb fc fc 00 00 fc fc fa fb fc fc
[   17.849614]                                                        ^
[   17.849692]  fff00000c5cff700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   17.849810]  fff00000c5cff780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   17.849858] ==================================================================

[   11.264582] ==================================================================
[   11.265541] BUG: KASAN: slab-use-after-free in kmalloc_uaf_16+0x47b/0x4c0
[   11.266312] Read of size 16 at addr ffff8881021715e0 by task kunit_try_catch/188
[   11.267082] 
[   11.267184] CPU: 1 UID: 0 PID: 188 Comm: kunit_try_catch Tainted: G    B            N  6.15.6-rc1 #1 PREEMPT(voluntary) 
[   11.267232] Tainted: [B]=BAD_PAGE, [N]=TEST
[   11.267243] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[   11.267265] Call Trace:
[   11.267277]  <TASK>
[   11.267293]  dump_stack_lvl+0x73/0xb0
[   11.267322]  print_report+0xd1/0x650
[   11.267346]  ? __virt_addr_valid+0x1db/0x2d0
[   11.267369]  ? kmalloc_uaf_16+0x47b/0x4c0
[   11.267390]  ? kasan_complete_mode_report_info+0x64/0x200
[   11.267414]  ? kmalloc_uaf_16+0x47b/0x4c0
[   11.267435]  kasan_report+0x141/0x180
[   11.267458]  ? kmalloc_uaf_16+0x47b/0x4c0
[   11.267485]  __asan_report_load16_noabort+0x18/0x20
[   11.267517]  kmalloc_uaf_16+0x47b/0x4c0
[   11.267539]  ? __pfx_kmalloc_uaf_16+0x10/0x10
[   11.267562]  ? __schedule+0x10cc/0x2b60
[   11.267654]  ? __pfx_read_tsc+0x10/0x10
[   11.267676]  ? ktime_get_ts64+0x86/0x230
[   11.267710]  kunit_try_run_case+0x1a5/0x480
[   11.267732]  ? __pfx_kunit_try_run_case+0x10/0x10
[   11.267751]  ? _raw_spin_lock_irqsave+0xa1/0x100
[   11.267777]  ? _raw_spin_unlock_irqrestore+0x5f/0x90
[   11.267801]  ? __kthread_parkme+0x82/0x180
[   11.267824]  ? preempt_count_sub+0x50/0x80
[   11.267901]  ? __pfx_kunit_try_run_case+0x10/0x10
[   11.267923]  kunit_generic_run_threadfn_adapter+0x85/0xf0
[   11.267946]  ? __pfx_kunit_generic_run_threadfn_adapter+0x10/0x10
[   11.267981]  kthread+0x337/0x6f0
[   11.267998]  ? trace_preempt_on+0x20/0xc0
[   11.268022]  ? __pfx_kthread+0x10/0x10
[   11.268041]  ? _raw_spin_unlock_irq+0x47/0x80
[   11.268063]  ? calculate_sigpending+0x7b/0xa0
[   11.268085]  ? __pfx_kthread+0x10/0x10
[   11.268104]  ret_from_fork+0x41/0x80
[   11.268124]  ? __pfx_kthread+0x10/0x10
[   11.268143]  ret_from_fork_asm+0x1a/0x30
[   11.268174]  </TASK>
[   11.268185] 
[   11.281211] Allocated by task 188:
[   11.281528]  kasan_save_stack+0x45/0x70
[   11.282124]  kasan_save_track+0x18/0x40
[   11.282496]  kasan_save_alloc_info+0x3b/0x50
[   11.282886]  __kasan_kmalloc+0xb7/0xc0
[   11.283246]  __kmalloc_cache_noprof+0x189/0x420
[   11.283402]  kmalloc_uaf_16+0x15b/0x4c0
[   11.283588]  kunit_try_run_case+0x1a5/0x480
[   11.283971]  kunit_generic_run_threadfn_adapter+0x85/0xf0
[   11.284588]  kthread+0x337/0x6f0
[   11.284966]  ret_from_fork+0x41/0x80
[   11.285304]  ret_from_fork_asm+0x1a/0x30
[   11.285532] 
[   11.285607] Freed by task 188:
[   11.285717]  kasan_save_stack+0x45/0x70
[   11.286034]  kasan_save_track+0x18/0x40
[   11.286404]  kasan_save_free_info+0x3f/0x60
[   11.286822]  __kasan_slab_free+0x56/0x70
[   11.287258]  kfree+0x222/0x3f0
[   11.287554]  kmalloc_uaf_16+0x1d6/0x4c0
[   11.287803]  kunit_try_run_case+0x1a5/0x480
[   11.288020]  kunit_generic_run_threadfn_adapter+0x85/0xf0
[   11.288201]  kthread+0x337/0x6f0
[   11.288322]  ret_from_fork+0x41/0x80
[   11.288452]  ret_from_fork_asm+0x1a/0x30
[   11.288735] 
[   11.288908] The buggy address belongs to the object at ffff8881021715e0
[   11.288908]  which belongs to the cache kmalloc-16 of size 16
[   11.290256] The buggy address is located 0 bytes inside of
[   11.290256]  freed 16-byte region [ffff8881021715e0, ffff8881021715f0)
[   11.291346] 
[   11.291508] The buggy address belongs to the physical page:
[   11.292107] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x102171
[   11.292463] flags: 0x200000000000000(node=0|zone=2)
[   11.292901] page_type: f5(slab)
[   11.293302] raw: 0200000000000000 ffff888100041640 dead000000000122 0000000000000000
[   11.294013] raw: 0000000000000000 0000000080800080 00000000f5000000 0000000000000000
[   11.294473] page dumped because: kasan: bad access detected
[   11.294733] 
[   11.294903] Memory state around the buggy address:
[   11.295394]  ffff888102171480: 00 02 fc fc 00 02 fc fc 00 02 fc fc 00 02 fc fc
[   11.296150]  ffff888102171500: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc
[   11.296652] >ffff888102171580: fa fb fc fc fa fb fc fc 00 00 fc fc fa fb fc fc
[   11.297406]                                                        ^
[   11.297800]  ffff888102171600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   11.298278]  ffff888102171680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   11.298500] ==================================================================