KASAN: use-after-free Read in inet_twsk_kill

Status: fixed on 2023/02/24 13:50
Subsystems: net
[Documentation on labels]
Fix commit: fbb8295248e1 tcp: allocate tcp_death_row outside of struct netns_ipv4
First crash: 1641d, last: 1639d
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-6-1 KASAN: use-after-free Read in inet_twsk_kill 19 3 383d 388d 0/2 auto-obsoleted due to no activity on 2025/10/05 13:36

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in inet_twsk_kill+0x358/0x3c0 net/ipv4/inet_timewait_sock.c:46
Read of size 8 at addr ffff8880522384c0 by task swapper/0/0

CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.16.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255
 __kasan_report mm/kasan/report.c:442 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
 inet_twsk_kill+0x358/0x3c0 net/ipv4/inet_timewait_sock.c:46
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
 expire_timers kernel/time/timer.c:1466 [inline]
 __run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734
 __run_timers kernel/time/timer.c:1715 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:finish_task_switch.isra.0+0x323/0xb80 kernel/sched/core.c:4866
Code: d3 cc fb 07 85 c0 75 02 0f 0b 48 85 db 0f 85 25 01 00 00 4c 89 f7 e8 fc f7 ff ff e8 e7 7e 2d 00 fb 65 48 8b 1c 25 00 70 02 00 <48> 8d bb 80 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1
RSP: 0018:ffffffff8b807cb0 EFLAGS: 00000202
RAX: 00000000001987d3 RBX: ffffffff8b8bc6c0 RCX: 1ffffffff1b28941
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffffff8b807cf8 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff817e98b8 R11: 0000000000000001 R12: ffff8880b9c3a958
R13: ffff8880778c1d00 R14: ffff8880b9c39c00 R15: ffff8880b9c3a638
 context_switch kernel/sched/core.c:4989 [inline]
 __schedule+0xaba/0x4e90 kernel/sched/core.c:6296
 schedule_idle+0x57/0x90 kernel/sched/core.c:6397
 do_idle+0x303/0x590 kernel/sched/idle.c:334
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
 start_kernel+0x47a/0x49b init/main.c:1135
 secondary_startup_64_no_verify+0xc3/0xcb
 </TASK>

Allocated by task 6453:
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:437 [inline]
 __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:470
 kasan_slab_alloc include/linux/kasan.h:260 [inline]
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slub.c:3230 [inline]
 slab_alloc mm/slub.c:3238 [inline]
 kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3243
 kmem_cache_zalloc include/linux/slab.h:705 [inline]
 net_alloc net/core/net_namespace.c:407 [inline]
 copy_net_ns+0x125/0x760 net/core/net_namespace.c:462
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3048
 __do_sys_unshare kernel/fork.c:3119 [inline]
 __se_sys_unshare kernel/fork.c:3117 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3117
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff888052238000
 which belongs to the cache net_namespace of size 6528
The buggy address is located 1216 bytes inside of
 6528-byte region [ffff888052238000, ffff888052239980)
The buggy address belongs to the page:
page:ffffea0001488e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805223cf80 pfn:0x52238
head:ffffea0001488e00 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff88801a1f4701
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea000136cc00 dead000000000002 ffff888015385000
raw: ffff88805223cf80 0000000080040000 00000001ffffffff ffff88801a1f4701
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3634, ts 120977370628, free_ts 11438773712
 prep_new_page mm/page_alloc.c:2434 [inline]
 get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389
 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271
 alloc_slab_page mm/slub.c:1799 [inline]
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x28a/0x3b0 mm/slub.c:2004
 ___slab_alloc+0x87c/0xe90 mm/slub.c:3018
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105
 slab_alloc_node mm/slub.c:3196 [inline]
 slab_alloc mm/slub.c:3238 [inline]
 kmem_cache_alloc+0x35c/0x3a0 mm/slub.c:3243
 kmem_cache_zalloc include/linux/slab.h:705 [inline]
 net_alloc net/core/net_namespace.c:407 [inline]
 copy_net_ns+0x125/0x760 net/core/net_namespace.c:462
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3048
 __do_sys_unshare kernel/fork.c:3119 [inline]
 __se_sys_unshare kernel/fork.c:3117 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3117
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1352 [inline]
 free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404
 free_unref_page_prepare mm/page_alloc.c:3325 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3404
 free_contig_range+0xa8/0xf0 mm/page_alloc.c:9335
 destroy_args+0xa8/0x646 mm/debug_vm_pgtable.c:1016
 debug_vm_pgtable+0x2961/0x29f3 mm/debug_vm_pgtable.c:1330
 do_one_initcall+0x103/0x650 init/main.c:1297
 do_initcall_level init/main.c:1370 [inline]
 do_initcalls init/main.c:1386 [inline]
 do_basic_setup init/main.c:1405 [inline]
 kernel_init_freeable+0x6b1/0x73a init/main.c:1610
 kernel_init+0x1a/0x1d0 init/main.c:1499
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
 ffff888052238380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888052238400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888052238480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff888052238500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888052238580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess), 4 bytes skipped:
   0:	85 c0                	test   %eax,%eax
   2:	75 02                	jne    0x6
   4:	0f 0b                	ud2
   6:	48 85 db             	test   %rbx,%rbx
   9:	0f 85 25 01 00 00    	jne    0x134
   f:	4c 89 f7             	mov    %r14,%rdi
  12:	e8 fc f7 ff ff       	callq  0xfffff813
  17:	e8 e7 7e 2d 00       	callq  0x2d7f03
  1c:	fb                   	sti
  1d:	65 48 8b 1c 25 00 70 	mov    %gs:0x27000,%rbx
  24:	02 00
* 26:	48 8d bb 80 15 00 00 	lea    0x1580(%rbx),%rdi <-- trapping instruction
  2d:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  34:	fc ff df
  37:	48 89 fa             	mov    %rdi,%rdx
  3a:	48                   	rex.W
  3b:	c1                   	.byte 0xc1

Crashes (86):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/01/27 12:26 net-next-old 40cd4f1550d0 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 11:01 net-next-old 40cd4f1550d0 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 10:18 net-next-old 40cd4f1550d0 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 08:25 net-next-old 40cd4f1550d0 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 04:58 net-next-old 40cd4f1550d0 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 01:41 net-next-old 40cd4f1550d0 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 01:37 net-next-old 40cd4f1550d0 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 22:46 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 22:02 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 21:52 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 21:07 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 21:06 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 20:55 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 18:01 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 16:50 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 14:41 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 14:16 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 13:30 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 10:30 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 10:24 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 10:21 net-next-old ab14f1802cfb 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 08:57 net-next-old 6b0671a23dd6 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 07:57 net-next-old 6b0671a23dd6 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 07:10 net-next-old 6b0671a23dd6 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 07:09 net-next-old 6b0671a23dd6 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/26 00:00 net-next-old 6b0671a23dd6 2cbffd88 .config console log report info ci-upstream-net-kasan-gce KASAN: use-after-free Read in inet_twsk_kill
2022/01/28 04:32 linux-next 0eb96e2c58c0 495e00c5 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/28 04:27 linux-next 0eb96e2c58c0 495e00c5 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/28 02:45 linux-next 0eb96e2c58c0 64a8e201 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 23:35 linux-next 0eb96e2c58c0 64a8e201 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 20:31 linux-next 0eb96e2c58c0 64a8e201 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 19:22 linux-next 0eb96e2c58c0 64a8e201 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 17:57 linux-next 0eb96e2c58c0 64a8e201 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 16:52 linux-next 0eb96e2c58c0 64a8e201 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 14:15 linux-next 0eb96e2c58c0 2cbffd88 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 07:04 linux-next 0eb96e2c58c0 2cbffd88 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 05:48 linux-next 0eb96e2c58c0 2cbffd88 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 05:40 linux-next 0eb96e2c58c0 2cbffd88 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 05:39 linux-next 0eb96e2c58c0 2cbffd88 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 05:36 linux-next 0eb96e2c58c0 2cbffd88 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 04:42 linux-next 0eb96e2c58c0 2cbffd88 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 04:41 linux-next 0eb96e2c58c0 2cbffd88 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 04:36 linux-next 0eb96e2c58c0 2cbffd88 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 03:54 linux-next 0eb96e2c58c0 2cbffd88 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in inet_twsk_kill
2022/01/27 11:10 net-next-old 40cd4f1550d0 2cbffd88 .config console log report info ci-upstream-net-kasan-gce general protection fault in inet_twsk_kill
* Struck through repros no longer work on HEAD.