================================================================== BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:378 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler net/ipv4/tcp_timer.c:624 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler+0x998/0x9f0 net/ipv4/tcp_timer.c:594 Read of size 1 at addr ffff88807b562385 by task dhcpcd-run-hook/12571 CPU: 0 PID: 12571 Comm: dhcpcd-run-hook Not tainted 6.0.0-syzkaller-02734-g0326074ff465 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold+0x2ba/0x719 mm/kasan/report.c:433 kasan_report+0xb1/0x1e0 mm/kasan/report.c:495 tcp_probe_timer net/ipv4/tcp_timer.c:378 [inline] tcp_write_timer_handler net/ipv4/tcp_timer.c:624 [inline] tcp_write_timer_handler+0x998/0x9f0 net/ipv4/tcp_timer.c:594 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:637 call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers.part.0+0x674/0xa80 kernel/time/timer.c:1790 __run_timers kernel/time/timer.c:1768 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803 __do_softirq+0x1d0/0x9c8 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:lock_acquire+0x1ef/0x570 kernel/locking/lockdep.c:5634 Code: f6 a3 7e 83 f8 01 0f 85 e8 02 00 00 9c 58 f6 c4 02 0f 85 fb 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: 0018:ffffc9000383f948 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92000707f2b RCX: ffffffff815e2cde RDX: 1ffff11004d6b8ae RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff90903957 R10: fffffbfff212072a R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88807866b890 R15: 0000000000000000 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:349 [inline] browse_rb mm/mmap.c:315 [inline] validate_mm+0x438/0x800 mm/mmap.c:382 __vma_adjust+0x1097/0x24a0 mm/mmap.c:980 vma_adjust include/linux/mm.h:2584 [inline] __split_vma+0x2b3/0x550 mm/mmap.c:2717 split_vma+0x95/0xd0 mm/mmap.c:2746 mprotect_fixup+0x758/0x970 mm/mprotect.c:614 do_mprotect_pkey+0x6c5/0x9e0 mm/mprotect.c:781 __do_sys_mprotect mm/mprotect.c:808 [inline] __se_sys_mprotect mm/mprotect.c:805 [inline] __x64_sys_mprotect+0x74/0xb0 mm/mprotect.c:805 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+0x63/0xcd RIP: 0033:0x7fcd44c80297 Code: 44 00 00 b8 0b 00 00 00 0f 05 48 3d 01 f0 ff ff 73 01 c3 48 8d 0d 21 1f 01 00 f7 d8 89 01 48 83 c8 ff c3 b8 0a 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8d 0d 01 1f 01 00 f7 d8 89 01 48 83 RSP: 002b:00007ffeb03802f8 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 00007fcd44c5e000 RCX: 00007fcd44c80297 RDX: 0000000000000001 RSI: 0000000000003000 RDI: 00007fcd44c5a000 RBP: 00007ffeb0380410 R08: 0000000000000000 R09: 00007fcd44bdb469 R10: 00007fcd44c5c2c8 R11: 0000000000000206 R12: 00007fcd44c5e000 R13: 0000000000000007 R14: 000001f100000007 R15: 00007fcd44ba0af0 Allocated by task 3638: 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:437 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:470 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:727 [inline] slab_alloc_node mm/slub.c:3248 [inline] slab_alloc mm/slub.c:3256 [inline] __kmem_cache_alloc_lru mm/slub.c:3263 [inline] kmem_cache_alloc+0x267/0x3b0 mm/slub.c:3273 kmem_cache_zalloc include/linux/slab.h:723 [inline] net_alloc net/core/net_namespace.c:403 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:458 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:3181 __do_sys_unshare kernel/fork.c:3252 [inline] __se_sys_unshare kernel/fork.c:3250 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3250 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+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 insert_work+0x48/0x350 kernel/workqueue.c:1358 __queue_work+0x625/0x1200 kernel/workqueue.c:1517 call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1514 [inline] __run_timers.part.0+0x4a3/0xa80 kernel/time/timer.c:1790 __run_timers kernel/time/timer.c:1768 [inline] run_timer_softirq+0x152/0x1d0 kernel/time/timer.c:1805 __do_softirq+0x1d0/0x9c8 kernel/softirq.c:571 The buggy address belongs to the object at ffff88807b561c40 which belongs to the cache net_namespace of size 6976 The buggy address is located 1861 bytes inside of 6976-byte region [ffff88807b561c40, ffff88807b563780) The buggy address belongs to the physical page: page:ffffea0001ed5800 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807b561c40 pfn:0x7b560 head:ffffea0001ed5800 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88806eae8f41 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00008dae00 dead000000000002 ffff8880119d43c0 raw: ffff88807b561c40 0000000080040000 00000001ffffffff ffff88806eae8f41 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 3640, tgid 3640 (syz-executor.1), ts 140453491553, free_ts 140438910876 prep_new_page mm/page_alloc.c:2532 [inline] get_page_from_freelist+0x109b/0x2ce0 mm/page_alloc.c:4283 __alloc_pages+0x1c7/0x510 mm/page_alloc.c:5549 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:1829 [inline] allocate_slab+0x27e/0x3d0 mm/slub.c:1974 new_slab mm/slub.c:2034 [inline] ___slab_alloc+0x84f/0xe80 mm/slub.c:3036 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3123 slab_alloc_node mm/slub.c:3214 [inline] slab_alloc mm/slub.c:3256 [inline] __kmem_cache_alloc_lru mm/slub.c:3263 [inline] kmem_cache_alloc+0x38c/0x3b0 mm/slub.c:3273 kmem_cache_zalloc include/linux/slab.h:723 [inline] net_alloc net/core/net_namespace.c:403 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:458 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:3181 __do_sys_unshare kernel/fork.c:3252 [inline] __se_sys_unshare kernel/fork.c:3250 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3250 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+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1449 [inline] free_pcp_prepare+0x5e4/0xd20 mm/page_alloc.c:1499 free_unref_page_prepare mm/page_alloc.c:3380 [inline] free_unref_page+0x19/0x4d0 mm/page_alloc.c:3476 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2553 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:447 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:727 [inline] slab_alloc_node mm/slub.c:3248 [inline] slab_alloc mm/slub.c:3256 [inline] __kmem_cache_alloc_lru mm/slub.c:3263 [inline] kmem_cache_alloc+0x267/0x3b0 mm/slub.c:3273 kmem_cache_zalloc include/linux/slab.h:723 [inline] lsm_file_alloc security/security.c:573 [inline] security_file_alloc+0x34/0x170 security/security.c:1527 __alloc_file+0xd9/0x270 fs/file_table.c:143 alloc_empty_file+0x6d/0x170 fs/file_table.c:187 path_openat+0xe7/0x28f0 fs/namei.c:3677 do_filp_open+0x1b6/0x400 fs/namei.c:3718 do_sys_openat2+0x16d/0x4c0 fs/open.c:1313 do_sys_open fs/open.c:1329 [inline] __do_sys_openat fs/open.c:1345 [inline] __se_sys_openat fs/open.c:1340 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1340 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+0x63/0xcd Memory state around the buggy address: ffff88807b562280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807b562300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807b562380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807b562400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807b562480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: f6 a3 7e 83 f8 01 mulb 0x1f8837e(%rbx) 6: 0f 85 e8 02 00 00 jne 0x2f4 c: 9c pushfq d: 58 pop %rax e: f6 c4 02 test $0x2,%ah 11: 0f 85 fb 02 00 00 jne 0x312 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