================================================================== 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 ffff888024dfbda5 by task syz-executor.2/12236 CPU: 1 PID: 12236 Comm: syz-executor.2 Not tainted 6.0.0-rc1-next-20220819-syzkaller #0 BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1521 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 12236, name: syz-executor.2 preempt_count: 102, expected: 0 RCU nest depth: 0, expected: 0 3 locks held by syz-executor.2/12236: #0: ffffffff8d7b1e28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8d7b1e28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3e5/0xca0 net/core/rtnetlink.c:6087 #1: ffffc900001e0d70 ((&icsk->icsk_retransmit_timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:31 [inline] #1: ffffc900001e0d70 ((&icsk->icsk_retransmit_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 kernel/time/timer.c:1464 #2: ffff8880207fb0b0 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:349 [inline] #2: ffff8880207fb0b0 (k-slock-AF_INET){+.-.}-{2:2}, at: tcp_write_timer+0x26/0x2b0 net/ipv4/tcp_timer.c:635 irq event stamp: 42919 hardirqs last enabled at (42918): [] seqcount_lockdep_reader_access include/linux/seqlock.h:104 [inline] hardirqs last enabled at (42918): [] timekeeping_get_delta kernel/time/timekeeping.c:254 [inline] hardirqs last enabled at (42918): [] timekeeping_get_ns kernel/time/timekeeping.c:388 [inline] hardirqs last enabled at (42918): [] ktime_get+0x38a/0x470 kernel/time/timekeeping.c:848 hardirqs last disabled at (42919): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (42919): [] _raw_spin_lock_irqsave+0x4e/0x50 kernel/locking/spinlock.c:162 softirqs last enabled at (42908): [] spin_unlock_bh include/linux/spinlock.h:394 [inline] softirqs last enabled at (42908): [] clusterip_netdev_event+0x419/0x650 net/ipv4/netfilter/ipt_CLUSTERIP.c:233 softirqs last disabled at (42911): [] invoke_softirq kernel/softirq.c:445 [inline] softirqs last disabled at (42911): [] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650 Preemption disabled at: [] softirq_handle_begin kernel/softirq.c:409 [inline] [] __do_softirq+0xe1/0x9c6 kernel/softirq.c:547 CPU: 1 PID: 12236 Comm: syz-executor.2 Not tainted 6.0.0-rc1-next-20220819-syzkaller #0 syz-executor.2[12236] cmdline: /root/syz-executor.2 exec Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Call Trace: __dump_stack lib/dump_stack.c:122 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:140 __might_resched.cold+0x222/0x26b kernel/sched/core.c:9896 down_read_killable+0x75/0x490 kernel/locking/rwsem.c:1521 mmap_read_lock_killable include/linux/mmap_lock.h:126 [inline] __access_remote_vm+0xac/0x6f0 mm/memory.c:5461 get_mm_cmdline.part.0+0x217/0x620 fs/proc/base.c:299 get_mm_cmdline fs/proc/base.c:367 [inline] get_task_cmdline_kernel+0x1d9/0x220 fs/proc/base.c:367 dump_stack_print_cmdline.part.0+0x82/0x150 lib/dump_stack.c:61 dump_stack_print_cmdline lib/dump_stack.c:89 [inline] dump_stack_print_info+0x185/0x190 lib/dump_stack.c:97 __dump_stack lib/dump_stack.c:121 [inline] dump_stack_lvl+0xc1/0x134 lib/dump_stack.c:140 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+0x1d3/0x9c6 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:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:notifier_call_chain+0x143/0x200 kernel/notifier.c:78 Code: 00 e8 e1 43 2b 00 31 ff 89 de e8 98 40 2b 00 85 db 74 78 4d 89 ef e8 cc 43 2b 00 49 8d 7f 08 48 89 f8 48 c1 e8 03 80 3c 28 00 <75> 76 4c 89 f8 4d 8b 6f 08 48 c1 e8 03 80 3c 28 00 75 6c 49 8b 3f RSP: 0018:ffffc9000379f130 EFLAGS: 00000246 RAX: 1ffffffff1b323ed RBX: 00000000ffffffc8 RCX: 0000000000000000 RDX: ffff888073f51d80 RSI: ffffffff8150d184 RDI: ffffffff8d991f68 RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 00000000ffffffc8 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff8d991f60 R14: 0000000000000000 R15: ffffffff8d991f60 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1945 __netdev_upper_dev_link+0x302/0x7f0 net/core/dev.c:7657 netdev_master_upper_dev_link+0x98/0xd0 net/core/dev.c:7738 batadv_hardif_enable_interface+0x1d7/0xac0 net/batman-adv/hard-interface.c:712 batadv_softif_slave_add+0x64/0x130 net/batman-adv/soft-interface.c:839 do_set_master+0x1c8/0x220 net/core/rtnetlink.c:2577 do_setlink+0x9e7/0x3bb0 net/core/rtnetlink.c:2787 __rtnl_newlink+0xd6a/0x17e0 net/core/rtnetlink.c:3546 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3593 rtnetlink_rcv_msg+0x43a/0xca0 net/core/rtnetlink.c:6090 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2501 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: 0033:0x7fbeb463c03c 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:00007ffe748e41a0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fbeb56d4320 RCX: 00007fbeb463c03c RDX: 0000000000000028 RSI: 00007fbeb56d4370 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffe748e41f4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fbeb56d4370 R14: 0000000000000003 R15: 0000000000000000 syz-executor.2[12236] cmdline: /root/syz-executor.2 exec Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Call Trace: __dump_stack lib/dump_stack.c:122 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:140 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+0x1d3/0x9c6 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:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:notifier_call_chain+0x143/0x200 kernel/notifier.c:78 Code: 00 e8 e1 43 2b 00 31 ff 89 de e8 98 40 2b 00 85 db 74 78 4d 89 ef e8 cc 43 2b 00 49 8d 7f 08 48 89 f8 48 c1 e8 03 80 3c 28 00 <75> 76 4c 89 f8 4d 8b 6f 08 48 c1 e8 03 80 3c 28 00 75 6c 49 8b 3f RSP: 0018:ffffc9000379f130 EFLAGS: 00000246 RAX: 1ffffffff1b323ed RBX: 00000000ffffffc8 RCX: 0000000000000000 RDX: ffff888073f51d80 RSI: ffffffff8150d184 RDI: ffffffff8d991f68 RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 00000000ffffffc8 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff8d991f60 R14: 0000000000000000 R15: ffffffff8d991f60 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1945 __netdev_upper_dev_link+0x302/0x7f0 net/core/dev.c:7657 netdev_master_upper_dev_link+0x98/0xd0 net/core/dev.c:7738 batadv_hardif_enable_interface+0x1d7/0xac0 net/batman-adv/hard-interface.c:712 batadv_softif_slave_add+0x64/0x130 net/batman-adv/soft-interface.c:839 do_set_master+0x1c8/0x220 net/core/rtnetlink.c:2577 do_setlink+0x9e7/0x3bb0 net/core/rtnetlink.c:2787 __rtnl_newlink+0xd6a/0x17e0 net/core/rtnetlink.c:3546 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3593 rtnetlink_rcv_msg+0x43a/0xca0 net/core/rtnetlink.c:6090 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2501 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: 0033:0x7fbeb463c03c 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:00007ffe748e41a0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fbeb56d4320 RCX: 00007fbeb463c03c RDX: 0000000000000028 RSI: 00007fbeb56d4370 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffe748e41f4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fbeb56d4370 R14: 0000000000000003 R15: 0000000000000000 Allocated by task 3623: 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:3243 [inline] slab_alloc mm/slub.c:3251 [inline] __kmem_cache_alloc_lru mm/slub.c:3258 [inline] kmem_cache_alloc+0x267/0x3b0 mm/slub.c:3268 kmem_cache_zalloc include/linux/slab.h:729 [inline] net_alloc net/core/net_namespace.c:404 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:459 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:227 ksys_unshare+0x445/0x920 kernel/fork.c:3194 __do_sys_unshare kernel/fork.c:3265 [inline] __se_sys_unshare kernel/fork.c:3263 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3263 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+0x625/0x1210 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+0x1d3/0x9c6 kernel/softirq.c:571 Second to 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+0x625/0x1210 kernel/workqueue.c:1517 queue_work_on+0xee/0x110 kernel/workqueue.c:1545 queue_work include/linux/workqueue.h:503 [inline] schedule_work include/linux/workqueue.h:564 [inline] xfrm_hash_grow_check net/xfrm/xfrm_state.c:1025 [inline] xfrm_hash_grow_check net/xfrm/xfrm_state.c:1020 [inline] xfrm_state_find+0x4af1/0x4f10 net/xfrm/xfrm_state.c:1185 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:2393 [inline] xfrm_tmpl_resolve+0x2f3/0xd40 net/xfrm/xfrm_policy.c:2438 xfrm_resolve_and_create_bundle+0x123/0x2620 net/xfrm/xfrm_policy.c:2731 xfrm_lookup_with_ifid+0x22a/0x2260 net/xfrm/xfrm_policy.c:3065 xfrm_lookup net/xfrm/xfrm_policy.c:3194 [inline] xfrm_lookup_route+0x36/0x1e0 net/xfrm/xfrm_policy.c:3205 ip_route_output_flow+0x114/0x150 net/ipv4/route.c:2880 udp_sendmsg+0x1963/0x2740 net/ipv4/udp.c:1222 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:819 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:734 ____sys_sendmsg+0x334/0x810 net/socket.c:2482 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2536 __sys_sendmmsg+0x18b/0x460 net/socket.c:2622 __do_sys_sendmmsg net/socket.c:2651 [inline] __se_sys_sendmmsg net/socket.c:2648 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2648 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 The buggy address belongs to the object at ffff888024dfb700 which belongs to the cache net_namespace of size 6784 The buggy address is located 1701 bytes inside of 6784-byte region [ffff888024dfb700, ffff888024dfd180) The buggy address belongs to the physical page: page:ffffea0000937e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888024dfb700 pfn:0x24df8 head:ffffea0000937e00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff888024ffe841 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00014dda00 dead000000000002 ffff8881400073c0 raw: ffff888024dfb700 0000000080040001 00000001ffffffff ffff888024ffe841 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 3625, tgid 3625 (syz-executor.1), ts 54174793890, free_ts 54168168000 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:5507 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2272 alloc_slab_page mm/slub.c:1824 [inline] allocate_slab+0x27e/0x3d0 mm/slub.c:1969 new_slab mm/slub.c:2029 [inline] ___slab_alloc+0x7f1/0xe10 mm/slub.c:3031 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3118 slab_alloc_node mm/slub.c:3209 [inline] slab_alloc mm/slub.c:3251 [inline] __kmem_cache_alloc_lru mm/slub.c:3258 [inline] kmem_cache_alloc+0x38c/0x3b0 mm/slub.c:3268 kmem_cache_zalloc include/linux/slab.h:729 [inline] net_alloc net/core/net_namespace.c:404 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:459 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:227 ksys_unshare+0x445/0x920 kernel/fork.c:3194 __do_sys_unshare kernel/fork.c:3265 [inline] __se_sys_unshare kernel/fork.c:3263 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3263 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:2548 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:3243 [inline] slab_alloc mm/slub.c:3251 [inline] __kmem_cache_alloc_lru mm/slub.c:3258 [inline] kmem_cache_alloc+0x267/0x3b0 mm/slub.c:3268 prepare_creds+0x3f/0x7b0 kernel/cred.c:260 access_override_creds fs/open.c:376 [inline] do_faccessat+0x3f4/0x850 fs/open.c:440 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: ffff888024dfbc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888024dfbd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888024dfbd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888024dfbe00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888024dfbe80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 00 e8 add %ch,%al 2: e1 43 loope 0x47 4: 2b 00 sub (%rax),%eax 6: 31 ff xor %edi,%edi 8: 89 de mov %ebx,%esi a: e8 98 40 2b 00 callq 0x2b40a7 f: 85 db test %ebx,%ebx 11: 74 78 je 0x8b 13: 4d 89 ef mov %r13,%r15 16: e8 cc 43 2b 00 callq 0x2b43e7 1b: 49 8d 7f 08 lea 0x8(%r15),%rdi 1f: 48 89 f8 mov %rdi,%rax 22: 48 c1 e8 03 shr $0x3,%rax 26: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1) * 2a: 75 76 jne 0xa2 <-- trapping instruction 2c: 4c 89 f8 mov %r15,%rax 2f: 4d 8b 6f 08 mov 0x8(%r15),%r13 33: 48 c1 e8 03 shr $0x3,%rax 37: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1) 3b: 75 6c jne 0xa9 3d: 49 8b 3f mov (%r15),%rdi