================================================================== BUG: KASAN: use-after-free in tcp_retransmit_timer+0x2f87/0x3400 net/ipv4/tcp_timer.c:509 Read of size 8 at addr ffff8880742d1f00 by task syz-executor.0/7725 CPU: 0 PID: 7725 Comm: syz-executor.0 Not tainted 6.0.0-syzkaller-02765-g62c69e89e81b #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_retransmit_timer+0x2f87/0x3400 net/ipv4/tcp_timer.c:509 tcp_write_timer_handler net/ipv4/tcp_timer.c:620 [inline] tcp_write_timer_handler+0x4de/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:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:166 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:200 Code: 48 89 ef 5d e9 a1 6b 4c 00 5d be 03 00 00 00 e9 b6 09 83 02 66 0f 1f 44 00 00 48 8b be a8 01 00 00 e8 b4 ff ff ff 31 c0 c3 90 <65> 8b 05 c9 59 87 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b RSP: 0018:ffffc900032fe8d8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88807aa9bb00 RSI: ffffffff8160b4d5 RDI: 0000000000000007 RBP: ffffc900032fea80 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000001 R13: ffffffff91192da0 R14: 0000000000000200 R15: ffffffff8ca32b38 console_emit_next_record.constprop.0+0x4fb/0x840 arch/x86/include/asm/irqflags.h:45 console_flush_all kernel/printk/printk.c:2794 [inline] console_unlock+0x37a/0x5a0 kernel/printk/printk.c:2861 vprintk_emit+0x1b9/0x5f0 kernel/printk/printk.c:2271 dev_vprintk_emit+0x36e/0x3b2 drivers/base/core.c:4736 dev_printk_emit+0xba/0xf1 drivers/base/core.c:4747 __netdev_printk+0x1c6/0x27a net/core/dev.c:11209 netdev_info+0xd7/0x109 net/core/dev.c:11264 nsim_udp_tunnel_set_port.cold+0x9b/0xc8 drivers/net/netdevsim/udp_tunnels.c:34 udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:223 [inline] udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:246 [inline] __udp_tunnel_nic_device_sync.part.0+0x84b/0xcb0 net/ipv4/udp_tunnel_nic.c:289 __udp_tunnel_nic_device_sync net/ipv4/udp_tunnel_nic.c:283 [inline] udp_tunnel_nic_device_sync+0x108/0x180 net/ipv4/udp_tunnel_nic.c:312 __udp_tunnel_nic_add_port+0x66b/0xc60 net/ipv4/udp_tunnel_nic.c:531 udp_tunnel_nic_add_port include/net/udp_tunnel.h:336 [inline] udp_tunnel_nic_add_port include/net/udp_tunnel.h:331 [inline] udp_tunnel_notify_add_rx_port+0x21e/0x3f0 net/ipv4/udp_tunnel_core.c:127 geneve_socket_create drivers/net/geneve.c:604 [inline] geneve_sock_add+0x957/0xd80 drivers/net/geneve.c:679 geneve_open+0xd2/0x1c0 drivers/net/geneve.c:721 __dev_open+0x297/0x4d0 net/core/dev.c:1432 __dev_change_flags+0x583/0x750 net/core/dev.c:8539 dev_change_flags+0x93/0x170 net/core/dev.c:8610 do_setlink+0x9f1/0x3bb0 net/core/rtnetlink.c:2788 __rtnl_newlink+0xd6a/0x17e0 net/core/rtnetlink.c:3547 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3594 rtnetlink_rcv_msg+0x43a/0xca0 net/core/rtnetlink.c:6091 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2540 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:734 __sys_sendto+0x236/0x340 net/socket.c:2117 __do_sys_sendto net/socket.c:2129 [inline] __se_sys_sendto net/socket.c:2125 [inline] __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2125 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: 0033:0x7f299da3d4fc Code: fa fa ff ff 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 20 fb ff ff 48 8b RSP: 002b:00007ffc5e6e6830 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f299eae4320 RCX: 00007f299da3d4fc RDX: 000000000000002c RSI: 00007f299eae4370 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffc5e6e6884 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007f299eae4370 R14: 0000000000000003 R15: 0000000000000000 Allocated by task 5617: 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 Freed by task 5300: 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:367 [inline] ____kasan_slab_free+0x166/0x1c0 mm/kasan/common.c:329 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1759 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785 slab_free mm/slub.c:3539 [inline] kmem_cache_free+0xeb/0x5b0 mm/slub.c:3556 net_free net/core/net_namespace.c:432 [inline] net_free net/core/net_namespace.c:428 [inline] cleanup_net+0x8ba/0xb00 net/core/net_namespace.c:615 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 The buggy address belongs to the object at ffff8880742d1c40 which belongs to the cache net_namespace of size 6976 The buggy address is located 704 bytes inside of 6976-byte region [ffff8880742d1c40, ffff8880742d3780) The buggy address belongs to the physical page: page:ffffea0001d0b400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880742d0000 pfn:0x742d0 head:ffffea0001d0b400 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88807f0d6841 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff8880119d43c0 raw: ffff8880742d0000 0000000080040002 00000001ffffffff ffff88807f0d6841 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 4156, tgid 4152 (syz-executor.3), ts 162475130884, free_ts 162458242530 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 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x304d/0x7090 kernel/fork.c:2257 kernel_clone+0xe7/0xab0 kernel/fork.c:2671 __do_sys_clone+0xba/0x100 kernel/fork.c:2805 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] __alloc_file+0x21/0x270 fs/file_table.c:138 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: ffff8880742d1e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880742d1e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880742d1f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880742d1f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880742d2000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 48 89 ef mov %rbp,%rdi 3: 5d pop %rbp 4: e9 a1 6b 4c 00 jmpq 0x4c6baa 9: 5d pop %rbp a: be 03 00 00 00 mov $0x3,%esi f: e9 b6 09 83 02 jmpq 0x28309ca 14: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 1a: 48 8b be a8 01 00 00 mov 0x1a8(%rsi),%rdi 21: e8 b4 ff ff ff callq 0xffffffda 26: 31 c0 xor %eax,%eax 28: c3 retq 29: 90 nop * 2a: 65 8b 05 c9 59 87 7e mov %gs:0x7e8759c9(%rip),%eax # 0x7e8759fa <-- trapping instruction 31: 89 c1 mov %eax,%ecx 33: 48 8b 34 24 mov (%rsp),%rsi 37: 81 e1 00 01 00 00 and $0x100,%ecx 3d: 65 gs 3e: 48 rex.W 3f: 8b .byte 0x8b