================================================================== BUG: KASAN: use-after-free in inet_twsk_kill+0x358/0x3c0 net/ipv4/inet_timewait_sock.c:46 Read of size 8 at addr ffff88804eded440 by task kworker/0:10/9592 CPU: 0 PID: 9592 Comm: kworker/0:10 Not tainted 5.16.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: __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 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:kasan_check_range+0x134/0x180 mm/kasan/generic.c:190 Code: 85 d2 75 0b 48 89 da 48 29 c2 e9 55 ff ff ff 49 39 d2 75 17 49 0f be 02 41 83 e1 07 49 39 c1 7d 0a 5b b8 01 00 00 00 5d 41 5c 44 89 c2 e8 a3 ef ff ff 5b 83 f0 01 5d 41 5c c3 b8 01 00 00 00 RSP: 0018:ffffc900028efac0 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffffffff8d337e80 RCX: ffffffff815bc32f RDX: ffffed1004411ae1 RSI: 0000000000000008 RDI: ffff88802208d700 RBP: ffff88801c030000 R08: 0000000000000000 R09: ffff88802208d707 R10: ffffed1004411ae0 R11: 0000000000000001 R12: dffffc0000000000 R13: 0000000000000000 R14: ffff88802208d700 R15: ffffed1004411ae0 instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] test_ti_thread_flag include/linux/thread_info.h:118 [inline] need_resched include/linux/sched.h:2132 [inline] mutex_spin_on_owner+0x14f/0x2e0 kernel/locking/mutex.c:370 mutex_optimistic_spin kernel/locking/mutex.c:473 [inline] __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x3ec/0x12f0 kernel/locking/mutex.c:733 addrconf_dad_work+0xa3/0x1340 net/ipv6/addrconf.c:4052 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 14504: 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 ffff88804edecf80 which belongs to the cache net_namespace of size 6528 The buggy address is located 1216 bytes inside of 6528-byte region [ffff88804edecf80, ffff88804edee900) The buggy address belongs to the page: page:ffffea00013b7a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88804edecf80 pfn:0x4ede8 head:ffffea00013b7a00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88801d642981 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888144592000 raw: ffff88804edecf80 0000000080040003 00000001ffffffff ffff88801d642981 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4020, ts 130826048736, free_ts 130822198417 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 kvfree+0x42/0x50 mm/util.c:613 rhashtable_free_and_destroy+0x147/0x920 lib/rhashtable.c:1159 ila_xlat_exit_net+0x146/0x360 net/ipv6/ila/ila_xlat.c:626 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:168 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:598 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff88804eded300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804eded380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88804eded400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88804eded480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804eded500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 85 d2 test %edx,%edx 2: 75 0b jne 0xf 4: 48 89 da mov %rbx,%rdx 7: 48 29 c2 sub %rax,%rdx a: e9 55 ff ff ff jmpq 0xffffff64 f: 49 39 d2 cmp %rdx,%r10 12: 75 17 jne 0x2b 14: 49 0f be 02 movsbq (%r10),%rax 18: 41 83 e1 07 and $0x7,%r9d 1c: 49 39 c1 cmp %rax,%r9 1f: 7d 0a jge 0x2b 21: 5b pop %rbx 22: b8 01 00 00 00 mov $0x1,%eax 27: 5d pop %rbp 28: 41 5c pop %r12 * 2a: c3 retq <-- trapping instruction 2b: 44 89 c2 mov %r8d,%edx 2e: e8 a3 ef ff ff callq 0xffffefd6 33: 5b pop %rbx 34: 83 f0 01 xor $0x1,%eax 37: 5d pop %rbp 38: 41 5c pop %r12 3a: c3 retq 3b: b8 01 00 00 00 mov $0x1,%eax