================================================================== BUG: KASAN: use-after-free in inet_twsk_kill+0x358/0x3c0 net/ipv4/inet_timewait_sock.c:46 Read of size 8 at addr ffff88807a8904c0 by task syz-executor.4/28887 CPU: 1 PID: 28887 Comm: syz-executor.4 Not tainted 5.16.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 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:refill_stock+0x129/0x2f0 mm/memcontrol.c:2228 Code: 3c 03 0f 8e 4b 01 00 00 03 5d 08 83 fb 20 89 5d 08 77 1f 4d 85 e4 75 27 9c 58 f6 c4 02 0f 85 b5 00 00 00 4d 85 e4 74 01 fb 5b <5d> 41 5c 41 5d 41 5e c3 48 89 ef e8 a7 f4 ff ff 4d 85 e4 74 d9 e8 RSP: 0000:ffffc90005af7bf8 EFLAGS: 00000206 RAX: 0000000000000002 RBX: ffff88807de6c000 RCX: 1ffffffff1ffc83e RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8880b9d35e20 R08: 0000000000000001 R09: ffffffff8ffd0a37 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000200 R13: ffff88807de6c000 R14: 0000000000000001 R15: 0000000000000002 obj_cgroup_uncharge_pages+0x18/0x70 mm/memcontrol.c:2996 __memcg_kmem_uncharge_page+0xf5/0x1b0 mm/memcontrol.c:3070 free_pages_prepare mm/page_alloc.c:1344 [inline] free_pcp_prepare+0x384/0x870 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 pte_free include/asm-generic/pgalloc.h:102 [inline] do_fault mm/memory.c:4320 [inline] handle_pte_fault mm/memory.c:4570 [inline] __handle_mm_fault+0x1779/0x5110 mm/memory.c:4705 handle_mm_fault+0x1c8/0x790 mm/memory.c:4803 do_user_addr_fault+0x489/0x11c0 arch/x86/mm/fault.c:1397 handle_page_fault arch/x86/mm/fault.c:1484 [inline] exc_page_fault+0x9e/0x180 arch/x86/mm/fault.c:1540 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:568 RIP: 0033:0x7f0792c6307b Code: 48 85 c0 74 1b 48 83 f8 01 0f 85 5a 03 00 00 0f b7 44 24 18 66 c1 c0 08 0f b7 c0 48 89 44 24 18 48 8b 44 24 10 0f b7 54 24 18 <66> 89 10 e9 70 fe ff ff 48 83 7c 24 08 08 0f 85 09 03 00 00 48 8b RSP: 002b:00007ffc28091d30 EFLAGS: 00010246 RAX: 0000000020007442 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000206 RSI: 0000000000000000 RDI: 00005555564c72e8 RBP: 00007ffc28091e28 R08: 0000000000000000 R09: 0000000000000000 R10: 0000001b2f160000 R11: 0000000020007280 R12: 00007f0792dd4f6c R13: 00007f0792df3440 R14: 00007f0792dd4f60 R15: 0000000000000000 Allocated by task 26383: 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 ffff88807a890000 which belongs to the cache net_namespace of size 6528 The buggy address is located 1216 bytes inside of 6528-byte region [ffff88807a890000, ffff88807a891980) The buggy address belongs to the page: page:ffffea0001ea2400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807a890000 pfn:0x7a890 head:ffffea0001ea2400 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff8880226f7c41 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001345008 ffffea0001356a08 ffff888011924000 raw: ffff88807a890000 0000000000040003 00000001ffffffff ffff8880226f7c41 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 3638, ts 132635177889, free_ts 132634455100 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 skb_free_head net/core/skbuff.c:655 [inline] skb_release_data+0x65d/0x790 net/core/skbuff.c:677 skb_release_all net/core/skbuff.c:742 [inline] __kfree_skb net/core/skbuff.c:756 [inline] consume_skb net/core/skbuff.c:914 [inline] consume_skb+0xc2/0x160 net/core/skbuff.c:908 skb_free_datagram+0x1b/0x1f0 net/core/datagram.c:325 netlink_recvmsg+0x636/0xea0 net/netlink/af_netlink.c:1998 sock_recvmsg_nosec net/socket.c:948 [inline] sock_recvmsg net/socket.c:966 [inline] sock_recvmsg net/socket.c:962 [inline] ____sys_recvmsg+0x2c4/0x600 net/socket.c:2632 ___sys_recvmsg+0x127/0x200 net/socket.c:2674 __sys_recvmsg+0xe2/0x1a0 net/socket.c:2704 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 Memory state around the buggy address: ffff88807a890380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807a890400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807a890480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807a890500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807a890580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 3c 03 cmp $0x3,%al 2: 0f 8e 4b 01 00 00 jle 0x153 8: 03 5d 08 add 0x8(%rbp),%ebx b: 83 fb 20 cmp $0x20,%ebx e: 89 5d 08 mov %ebx,0x8(%rbp) 11: 77 1f ja 0x32 13: 4d 85 e4 test %r12,%r12 16: 75 27 jne 0x3f 18: 9c pushfq 19: 58 pop %rax 1a: f6 c4 02 test $0x2,%ah 1d: 0f 85 b5 00 00 00 jne 0xd8 23: 4d 85 e4 test %r12,%r12 26: 74 01 je 0x29 28: fb sti 29: 5b pop %rbx * 2a: 5d pop %rbp <-- trapping instruction 2b: 41 5c pop %r12 2d: 41 5d pop %r13 2f: 41 5e pop %r14 31: c3 retq 32: 48 89 ef mov %rbp,%rdi 35: e8 a7 f4 ff ff callq 0xfffff4e1 3a: 4d 85 e4 test %r12,%r12 3d: 74 d9 je 0x18 3f: e8 .byte 0xe8