================================================================== BUG: KASAN: use-after-free in inet_twsk_kill+0x358/0x3c0 net/ipv4/inet_timewait_sock.c:46 Read of size 8 at addr ffff8880474984c0 by task syz-executor.4/13942 CPU: 0 PID: 13942 Comm: syz-executor.4 Not tainted 5.17.0-rc1-next-20220127-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+0xa5/0x3e0 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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194 Code: 74 24 10 e8 4a 26 ff f7 48 89 ef e8 f2 9b ff f7 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 b3 50 f2 f7 65 8b 05 4c 5d a4 76 85 c0 74 0a 5b 5d c3 e8 90 a4 RSP: 0018:ffffc90004d7f788 EFLAGS: 00000206 RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff201026e RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffffffff8b810db0 R08: 0000000000000001 R09: ffffffff8fff2abf R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8b810db0 R13: ffffc90004d7f808 R14: ffffffff8b810df0 R15: ffffea00012fc8c0 spin_unlock_irqrestore include/linux/spinlock.h:409 [inline] folio_wake_bit+0x1e9/0x270 mm/filemap.c:1195 folio_unlock+0x93/0xc0 mm/filemap.c:1557 truncate_inode_pages_range+0x861/0x1520 mm/truncate.c:395 kill_bdev block/bdev.c:77 [inline] set_blocksize+0x2bd/0x370 block/bdev.c:153 sb_set_blocksize block/bdev.c:162 [inline] sb_min_blocksize+0xc8/0x1c0 block/bdev.c:178 fat_fill_super+0x2dc/0x36e0 fs/fat/inode.c:1646 mount_bdev+0x34d/0x410 fs/super.c:1367 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1497 do_new_mount fs/namespace.c:3010 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3340 do_mount fs/namespace.c:3353 [inline] __do_sys_mount fs/namespace.c:3561 [inline] __se_sys_mount fs/namespace.c:3538 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3538 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 RIP: 0033:0x7fd3aae6f58a 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:00007fd3a97e2f88 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000300 RCX: 00007fd3aae6f58a RDX: 0000000020001a80 RSI: 0000000020000180 RDI: 00007fd3a97e2fe0 RBP: 00007fd3a97e3020 R08: 00007fd3a97e3020 R09: 0000000020001a80 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020001a80 R13: 0000000020000180 R14: 00007fd3a97e2fe0 R15: 0000000020000080 Allocated by task 3627: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:469 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 Freed by task 11494: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x166/0x1a0 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:236 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 slab_free mm/slub.c:3509 [inline] kmem_cache_free+0xdb/0x3b0 mm/slub.c:3526 net_free net/core/net_namespace.c:436 [inline] net_free net/core/net_namespace.c:432 [inline] cleanup_net+0x8ba/0xb00 net/core/net_namespace.c:619 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff888047498000 which belongs to the cache net_namespace of size 6528 The buggy address is located 1216 bytes inside of 6528-byte region [ffff888047498000, ffff888047499980) The buggy address belongs to the page: page:ffffea00011d2600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88804749cf80 pfn:0x47498 head:ffffea00011d2600 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88806d7d3781 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea000067f400 dead000000000002 ffff8881406f6a00 raw: ffff88804749cf80 0000000080040001 00000001ffffffff ffff88806d7d3781 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 3627, ts 122863221333, free_ts 12940283870 prep_new_page mm/page_alloc.c:2434 [inline] get_page_from_freelist+0xa72/0x2f40 mm/page_alloc.c:4165 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5381 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+0x28d/0x380 mm/slub.c:2004 ___slab_alloc+0x6be/0xd60 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+0x414/0xb60 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+0xb1/0x180 mm/page_alloc.c:9327 destroy_args+0xa8/0x646 mm/debug_vm_pgtable.c:1016 debug_vm_pgtable+0x2a0e/0x2aa0 mm/debug_vm_pgtable.c:1330 do_one_initcall+0x103/0x650 init/main.c:1303 do_initcall_level init/main.c:1378 [inline] do_initcalls init/main.c:1394 [inline] do_basic_setup init/main.c:1413 [inline] kernel_init_freeable+0x6b1/0x73a init/main.c:1618 kernel_init+0x1a/0x1d0 init/main.c:1507 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff888047498380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888047498400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888047498480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888047498500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888047498580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 74 24 je 0x26 2: 10 e8 adc %ch,%al 4: 4a rex.WX 5: 26 ff f7 es push %rdi 8: 48 89 ef mov %rbp,%rdi b: e8 f2 9b ff f7 callq 0xf7ff9c02 10: 81 e3 00 02 00 00 and $0x200,%ebx 16: 75 25 jne 0x3d 18: 9c pushfq 19: 58 pop %rax 1a: f6 c4 02 test $0x2,%ah 1d: 75 2d jne 0x4c 1f: 48 85 db test %rbx,%rbx 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 b3 50 f2 f7 callq 0xf7f250e2 <-- trapping instruction 2f: 65 8b 05 4c 5d a4 76 mov %gs:0x76a45d4c(%rip),%eax # 0x76a45d82 36: 85 c0 test %eax,%eax 38: 74 0a je 0x44 3a: 5b pop %rbx 3b: 5d pop %rbp 3c: c3 retq 3d: e8 .byte 0xe8 3e: 90 nop 3f: a4 movsb %ds:(%rsi),%es:(%rdi)