Hay
Date
July 15, 2025, 2:09 p.m.

Environment
qemu-arm64
qemu-x86_64

[   17.864806] ==================================================================
[   17.864868] BUG: KASAN: slab-use-after-free in kmalloc_uaf_16+0x3bc/0x438
[   17.865571] Read of size 16 at addr fff00000c45d8b20 by task kunit_try_catch/170
[   17.865708] 
[   17.865933] CPU: 0 UID: 0 PID: 170 Comm: kunit_try_catch Tainted: G    B            N  6.15.7-rc1 #1 PREEMPT 
[   17.866451] Tainted: [B]=BAD_PAGE, [N]=TEST
[   17.866487] Hardware name: linux,dummy-virt (DT)
[   17.866520] Call trace:
[   17.866556]  show_stack+0x20/0x38 (C)
[   17.866633]  dump_stack_lvl+0x8c/0xd0
[   17.866688]  print_report+0x118/0x5d0
[   17.866744]  kasan_report+0xdc/0x128
[   17.866788]  __asan_report_load16_noabort+0x20/0x30
[   17.866855]  kmalloc_uaf_16+0x3bc/0x438
[   17.866902]  kunit_try_run_case+0x170/0x3f0
[   17.866949]  kunit_generic_run_threadfn_adapter+0x88/0x100
[   17.867013]  kthread+0x328/0x630
[   17.867059]  ret_from_fork+0x10/0x20
[   17.867124] 
[   17.867143] Allocated by task 170:
[   17.867170]  kasan_save_stack+0x3c/0x68
[   17.867390]  kasan_save_track+0x20/0x40
[   17.867787]  kasan_save_alloc_info+0x40/0x58
[   17.867971]  __kasan_kmalloc+0xd4/0xd8
[   17.868305]  __kmalloc_cache_noprof+0x16c/0x3c0
[   17.868389]  kmalloc_uaf_16+0x140/0x438
[   17.868922]  kunit_try_run_case+0x170/0x3f0
[   17.869016]  kunit_generic_run_threadfn_adapter+0x88/0x100
[   17.869353]  kthread+0x328/0x630
[   17.869447]  ret_from_fork+0x10/0x20
[   17.869532] 
[   17.869700] Freed by task 170:
[   17.869728]  kasan_save_stack+0x3c/0x68
[   17.869939]  kasan_save_track+0x20/0x40
[   17.870024]  kasan_save_free_info+0x4c/0x78
[   17.870064]  __kasan_slab_free+0x6c/0x98
[   17.870100]  kfree+0x214/0x3c8
[   17.870132]  kmalloc_uaf_16+0x190/0x438
[   17.870170]  kunit_try_run_case+0x170/0x3f0
[   17.870218]  kunit_generic_run_threadfn_adapter+0x88/0x100
[   17.870631]  kthread+0x328/0x630
[   17.870718]  ret_from_fork+0x10/0x20
[   17.870972] 
[   17.871095] The buggy address belongs to the object at fff00000c45d8b20
[   17.871095]  which belongs to the cache kmalloc-16 of size 16
[   17.871570] The buggy address is located 0 bytes inside of
[   17.871570]  freed 16-byte region [fff00000c45d8b20, fff00000c45d8b30)
[   17.871694] 
[   17.871753] The buggy address belongs to the physical page:
[   17.871785] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1045d8
[   17.872019] flags: 0xbfffe0000000000(node=0|zone=2|lastcpupid=0x1ffff)
[   17.872330] page_type: f5(slab)
[   17.872398] raw: 0bfffe0000000000 fff00000c0001640 dead000000000122 0000000000000000
[   17.872787] raw: 0000000000000000 0000000080800080 00000000f5000000 0000000000000000
[   17.872880] page dumped because: kasan: bad access detected
[   17.872961] 
[   17.873152] Memory state around the buggy address:
[   17.873449]  fff00000c45d8a00: fa fb fc fc fa fb fc fc 00 01 fc fc fa fb fc fc
[   17.873626]  fff00000c45d8a80: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc
[   17.873751] >fff00000c45d8b00: 00 00 fc fc fa fb fc fc fc fc fc fc fc fc fc fc
[   17.873793]                                ^
[   17.873825]  fff00000c45d8b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   17.873988]  fff00000c45d8c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   17.874059] ==================================================================

[   11.013409] ==================================================================
[   11.013929] BUG: KASAN: slab-use-after-free in kmalloc_uaf_16+0x47b/0x4c0
[   11.014675] Read of size 16 at addr ffff8881027e7480 by task kunit_try_catch/187
[   11.015465] 
[   11.015568] CPU: 1 UID: 0 PID: 187 Comm: kunit_try_catch Tainted: G    B            N  6.15.7-rc1 #1 PREEMPT(voluntary) 
[   11.015643] Tainted: [B]=BAD_PAGE, [N]=TEST
[   11.015655] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[   11.015674] Call Trace:
[   11.015685]  <TASK>
[   11.015699]  dump_stack_lvl+0x73/0xb0
[   11.015725]  print_report+0xd1/0x610
[   11.015748]  ? __virt_addr_valid+0x1db/0x2d0
[   11.015769]  ? kmalloc_uaf_16+0x47b/0x4c0
[   11.015789]  ? kasan_complete_mode_report_info+0x64/0x200
[   11.015810]  ? kmalloc_uaf_16+0x47b/0x4c0
[   11.015831]  kasan_report+0x141/0x180
[   11.015852]  ? kmalloc_uaf_16+0x47b/0x4c0
[   11.015889]  __asan_report_load16_noabort+0x18/0x20
[   11.015909]  kmalloc_uaf_16+0x47b/0x4c0
[   11.015930]  ? __pfx_kmalloc_uaf_16+0x10/0x10
[   11.015952]  ? __schedule+0x10cc/0x2b60
[   11.015974]  ? __pfx_read_tsc+0x10/0x10
[   11.015993]  ? ktime_get_ts64+0x86/0x230
[   11.016018]  kunit_try_run_case+0x1a5/0x480
[   11.016038]  ? __pfx_kunit_try_run_case+0x10/0x10
[   11.016056]  ? _raw_spin_lock_irqsave+0xa1/0x100
[   11.016079]  ? _raw_spin_unlock_irqrestore+0x5f/0x90
[   11.016102]  ? __kthread_parkme+0x82/0x180
[   11.016123]  ? preempt_count_sub+0x50/0x80
[   11.016147]  ? __pfx_kunit_try_run_case+0x10/0x10
[   11.016166]  kunit_generic_run_threadfn_adapter+0x85/0xf0
[   11.016188]  ? __pfx_kunit_generic_run_threadfn_adapter+0x10/0x10
[   11.016210]  kthread+0x337/0x6f0
[   11.016226]  ? trace_preempt_on+0x20/0xc0
[   11.016248]  ? __pfx_kthread+0x10/0x10
[   11.016265]  ? _raw_spin_unlock_irq+0x47/0x80
[   11.016285]  ? calculate_sigpending+0x7b/0xa0
[   11.016306]  ? __pfx_kthread+0x10/0x10
[   11.016322]  ret_from_fork+0x41/0x80
[   11.016342]  ? __pfx_kthread+0x10/0x10
[   11.016358]  ret_from_fork_asm+0x1a/0x30
[   11.016388]  </TASK>
[   11.016397] 
[   11.029328] Allocated by task 187:
[   11.029470]  kasan_save_stack+0x45/0x70
[   11.029617]  kasan_save_track+0x18/0x40
[   11.030135]  kasan_save_alloc_info+0x3b/0x50
[   11.030650]  __kasan_kmalloc+0xb7/0xc0
[   11.031208]  __kmalloc_cache_noprof+0x189/0x420
[   11.031645]  kmalloc_uaf_16+0x15b/0x4c0
[   11.032120]  kunit_try_run_case+0x1a5/0x480
[   11.032529]  kunit_generic_run_threadfn_adapter+0x85/0xf0
[   11.033115]  kthread+0x337/0x6f0
[   11.033440]  ret_from_fork+0x41/0x80
[   11.033826]  ret_from_fork_asm+0x1a/0x30
[   11.034123] 
[   11.034199] Freed by task 187:
[   11.034308]  kasan_save_stack+0x45/0x70
[   11.034443]  kasan_save_track+0x18/0x40
[   11.034575]  kasan_save_free_info+0x3f/0x60
[   11.034800]  __kasan_slab_free+0x56/0x70
[   11.035235]  kfree+0x222/0x3f0
[   11.035525]  kmalloc_uaf_16+0x1d6/0x4c0
[   11.035936]  kunit_try_run_case+0x1a5/0x480
[   11.036389]  kunit_generic_run_threadfn_adapter+0x85/0xf0
[   11.037031]  kthread+0x337/0x6f0
[   11.037410]  ret_from_fork+0x41/0x80
[   11.037744]  ret_from_fork_asm+0x1a/0x30
[   11.038286] 
[   11.038450] The buggy address belongs to the object at ffff8881027e7480
[   11.038450]  which belongs to the cache kmalloc-16 of size 16
[   11.039005] The buggy address is located 0 bytes inside of
[   11.039005]  freed 16-byte region [ffff8881027e7480, ffff8881027e7490)
[   11.039348] 
[   11.039420] The buggy address belongs to the physical page:
[   11.039591] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1027e7
[   11.039833] flags: 0x200000000000000(node=0|zone=2)
[   11.040052] page_type: f5(slab)
[   11.040173] raw: 0200000000000000 ffff888100041640 dead000000000122 0000000000000000
[   11.040727] raw: 0000000000000000 0000000080800080 00000000f5000000 0000000000000000
[   11.041061] page dumped because: kasan: bad access detected
[   11.041237] 
[   11.041333] Memory state around the buggy address:
[   11.041564]  ffff8881027e7380: 00 04 fc fc 00 04 fc fc 00 01 fc fc 00 01 fc fc
[   11.042060]  ffff8881027e7400: 00 04 fc fc 00 04 fc fc fa fb fc fc 00 00 fc fc
[   11.042335] >ffff8881027e7480: fa fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   11.042607]                    ^
[   11.042749]  ffff8881027e7500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   11.043047]  ffff8881027e7580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   11.043328] ==================================================================