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KASAN: slab-use-after-free Write in expire_timers

Status: auto-obsoleted due to no activity on 2023/08/23 09:02
Subsystems: mm acpi batman
[Documentation on labels]
Reported-by: syzbot+7403ea5e821ac5a30b92@syzkaller.appspotmail.com
First crash: 609d, last: 601d
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [kernel?] KASAN: slab-use-after-free Write in expire_timers 0 (1) 2023/05/03 20:17
▶ ▼ Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Write in expire_timers arm 1 767d 765d 0/28 auto-obsoleted due to no activity on 2023/03/20 12:09
upstream KMSAN: uninit-value in expire_timers (2) kernel 2 1369d 1405d 0/28 auto-closed as invalid on 2021/06/26 09:57
upstream KMSAN: uninit-value in expire_timers (3) ext4 1 1271d 1271d 0/28 auto-closed as invalid on 2021/10/02 12:28
android-54 BUG: unable to handle kernel paging request in expire_timers 3 1357d 1449d 0/2 auto-closed as invalid on 2021/08/07 04:23
upstream KMSAN: uninit-value in expire_timers (4) kernel 1 1142d 1142d 0/28 auto-closed as invalid on 2022/02/08 07:20
android-54 BUG: unable to handle kernel paging request in expire_timers (2) 6 704d 955d 0/2 auto-obsoleted due to no activity on 2023/05/22 09:21
android-54 general protection fault in expire_timers 1 1364d 1364d 0/2 auto-closed as invalid on 2021/07/30 19:44

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:901 [inline]
BUG: KASAN: slab-use-after-free in detach_timer kernel/time/timer.c:880 [inline]
BUG: KASAN: slab-use-after-free in expire_timers+0x476/0x4b0 kernel/time/timer.c:1734
Write of size 8 at addr ffff888028d29500 by task syz-executor.3/13686

CPU: 2 PID: 13686 Comm: syz-executor.3 Not tainted 6.3.0-syzkaller-12728-g348551ddaf31 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351
 print_report mm/kasan/report.c:462 [inline]
 kasan_report+0x11c/0x130 mm/kasan/report.c:572
 __hlist_del include/linux/list.h:901 [inline]
 detach_timer kernel/time/timer.c:880 [inline]
 expire_timers+0x476/0x4b0 kernel/time/timer.c:1734
 __run_timers kernel/time/timer.c:2022 [inline]
 __run_timers kernel/time/timer.c:1995 [inline]
 run_timer_softirq+0x326/0x910 kernel/time/timer.c:2035
 __do_softirq+0x1d4/0x905 kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x114/0x190 kernel/softirq.c:650
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:lock_acquire+0x1f5/0x520 kernel/locking/lockdep.c:5659
Code: 65 9d 7e 83 f8 01 0f 85 b9 02 00 00 9c 58 f6 c4 02 0f 85 a4 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24
RSP: 0000:ffffc90003cbf220 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff92000797e46 RCX: ffffffff8164ca56
RDX: 1ffff11004149c18 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff9151dd17
R10: fffffbfff22a3ba2 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8c90a3e0 R15: 0000000000000000
 fs_reclaim_acquire mm/page_alloc.c:3901 [inline]
 fs_reclaim_acquire+0xda/0x160 mm/page_alloc.c:3892
 might_alloc include/linux/sched/mm.h:303 [inline]
 prepare_alloc_pages+0x159/0x570 mm/page_alloc.c:4530
 __alloc_pages+0x149/0x4a0 mm/page_alloc.c:4748
 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2277
 folio_alloc+0x20/0x70 mm/mempolicy.c:2287
 filemap_alloc_folio+0x3c1/0x470 mm/filemap.c:976
 __filemap_get_folio+0x2a6/0x990 mm/filemap.c:1965
 pagecache_get_page+0x2e/0x270 mm/folio-compat.c:99
 find_or_create_page include/linux/pagemap.h:635 [inline]
 grow_dev_page fs/buffer.c:995 [inline]
 grow_buffers fs/buffer.c:1060 [inline]
 __getblk_slow+0x1f2/0x1230 fs/buffer.c:1087
 __getblk_gfp+0x72/0x80 fs/buffer.c:1382
 __getblk include/linux/buffer_head.h:420 [inline]
 reiserfs_breada+0x15f/0x470 fs/reiserfs/journal.c:2338
 journal_read fs/reiserfs/journal.c:2449 [inline]
 journal_init+0x23dd/0x64b0 fs/reiserfs/journal.c:2897
 reiserfs_fill_super+0xc5b/0x2eb0 fs/reiserfs/super.c:2022
 mount_bdev+0x357/0x420 fs/super.c:1380
 legacy_get_tree+0x109/0x220 fs/fs_context.c:610
 vfs_get_tree+0x8d/0x350 fs/super.c:1510
 do_new_mount fs/namespace.c:3039 [inline]
 path_mount+0x134b/0x1e40 fs/namespace.c:3369
 do_mount fs/namespace.c:3382 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount fs/namespace.c:3568 [inline]
 __x64_sys_mount+0x283/0x300 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fc3ca28d69a
Code: 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc3c8dfdf88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 000000000000ffb6 RCX: 00007fc3ca28d69a
RDX: 000000002000ffc0 RSI: 0000000020010000 RDI: 00007fc3c8dfdfe0
RBP: 00007fc3c8dfe020 R08: 00007fc3c8dfe020 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000002000ffc0
R13: 0000000020010000 R14: 00007fc3c8dfdfe0 R15: 0000000020010040
 </TASK>

Allocated by task 11731:
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 __kasan_slab_alloc+0x7f/0x90 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:186 [inline]
 slab_post_alloc_hook mm/slab.h:711 [inline]
 slab_alloc_node mm/slab.c:3256 [inline]
 slab_alloc mm/slab.c:3265 [inline]
 __kmem_cache_alloc_lru mm/slab.c:3442 [inline]
 kmem_cache_alloc+0x1bd/0x3f0 mm/slab.c:3451
 getname_flags.part.0+0x50/0x4f0 fs/namei.c:140
 getname_flags include/linux/audit.h:321 [inline]
 getname+0x92/0xd0 fs/namei.c:219
 do_sys_openat2+0xf5/0x4c0 fs/open.c:1350
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0x143/0x1f0 fs/open.c:1383
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 11731:
 kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:521
 ____kasan_slab_free mm/kasan/common.c:236 [inline]
 ____kasan_slab_free+0x13b/0x1a0 mm/kasan/common.c:200
 kasan_slab_free include/linux/kasan.h:162 [inline]
 __cache_free mm/slab.c:3389 [inline]
 __do_kmem_cache_free mm/slab.c:3576 [inline]
 kmem_cache_free mm/slab.c:3601 [inline]
 kmem_cache_free+0x105/0x370 mm/slab.c:3594
 putname fs/namei.c:273 [inline]
 putname+0x102/0x140 fs/namei.c:259
 do_sys_openat2+0x153/0x4c0 fs/open.c:1365
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0x143/0x1f0 fs/open.c:1383
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff888028d28b40
 which belongs to the cache names_cache of size 4096
The buggy address is located 2496 bytes inside of
 freed 4096-byte region [ffff888028d28b40, ffff888028d29b40)

The buggy address belongs to the physical page:
page:ffffea0000a34a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28d28
head:ffffea0000a34a00 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0x1()
raw: 00fff00000010200 ffff888040059f00 ffffea0000a7a590 ffffea0000a24d10
raw: 0000000000000000 ffff888028d28b40 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x2420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 11731, tgid 11731 (udevd), ts 458697775213, free_ts 458620276328
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1722
 prep_new_page mm/page_alloc.c:1729 [inline]
 get_page_from_freelist+0xf41/0x2c00 mm/page_alloc.c:3493
 __alloc_pages_slowpath.constprop.0+0x2e7/0x2170 mm/page_alloc.c:4293
 __alloc_pages+0x408/0x4a0 mm/page_alloc.c:4772
 __alloc_pages_node include/linux/gfp.h:237 [inline]
 kmem_getpages mm/slab.c:1360 [inline]
 cache_grow_begin+0x9b/0x3b0 mm/slab.c:2569
 cache_alloc_refill+0x27f/0x380 mm/slab.c:2942
 ____cache_alloc mm/slab.c:3018 [inline]
 ____cache_alloc mm/slab.c:3001 [inline]
 __do_cache_alloc mm/slab.c:3201 [inline]
 slab_alloc_node mm/slab.c:3249 [inline]
 slab_alloc mm/slab.c:3265 [inline]
 __kmem_cache_alloc_lru mm/slab.c:3442 [inline]
 kmem_cache_alloc+0x397/0x3f0 mm/slab.c:3451
 getname_flags.part.0+0x50/0x4f0 fs/namei.c:140
 getname_flags include/linux/audit.h:321 [inline]
 getname+0x92/0xd0 fs/namei.c:219
 do_sys_openat2+0xf5/0x4c0 fs/open.c:1350
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0x143/0x1f0 fs/open.c:1383
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1302 [inline]
 free_unref_page_prepare+0x62e/0xcb0 mm/page_alloc.c:2555
 free_unref_page+0x33/0x370 mm/page_alloc.c:2650
 slab_destroy mm/slab.c:1612 [inline]
 drain_freelist.isra.0+0xdd/0x130 mm/slab.c:2205
 cache_reap+0x1bd/0x2e0 mm/slab.c:3870
 process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405
 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2552
 kthread+0x344/0x440 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

Memory state around the buggy address:
 ffff888028d29400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888028d29480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888028d29500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff888028d29580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888028d29600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	65 9d                	gs popfq
   2:	7e 83                	jle    0xffffff87
   4:	f8                   	clc
   5:	01 0f                	add    %ecx,(%rdi)
   7:	85 b9 02 00 00 9c    	test   %edi,-0x63fffffe(%rcx)
   d:	58                   	pop    %rax
   e:	f6 c4 02             	test   $0x2,%ah
  11:	0f 85 a4 02 00 00    	jne    0x2bb
  17:	48 83 7c 24 08 00    	cmpq   $0x0,0x8(%rsp)
  1d:	74 01                	je     0x20
  1f:	fb                   	sti
  20:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  27:	fc ff df
* 2a:	48 01 c3             	add    %rax,%rbx <-- trapping instruction
  2d:	48 c7 03 00 00 00 00 	movq   $0x0,(%rbx)
  34:	48 c7 43 08 00 00 00 	movq   $0x0,0x8(%rbx)
  3b:	00
  3c:	48                   	rex.W
  3d:	8b                   	.byte 0x8b
  3e:	84                   	.byte 0x84
  3f:	24                   	.byte 0x24

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/05/03 15:12 upstream 348551ddaf31 b5918830 .config console log report info ci-qemu-upstream KASAN: slab-use-after-free Write in expire_timers
2023/04/26 19:00 upstream 0cfd8703e7da 19a3dabe .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Write in expire_timers
2023/05/02 18:53 upstream 865fdb08197e 48e0a81d .config console log report info ci-upstream-kasan-gce-386 KASAN: slab-use-after-free Write in expire_timers
2023/05/05 04:18 bpf 415d7a49cd79 518a39a6 .config console log report info ci-upstream-bpf-kasan-gce KASAN: slab-use-after-free Write in expire_timers
2023/05/05 02:28 net b9850ec0027c 518a39a6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Write in expire_timers
2023/05/03 20:17 linux-next 92e815cf07ed b5918830 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Write in expire_timers
2023/04/27 19:54 linux-next 84e2893b4573 6f5b1cc4 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: slab-use-after-free Write in expire_timers
* Struck through repros no longer work on HEAD.