================================================================== BUG: KASAN: use-after-free in smc_fback_error_report+0x96/0xa0 net/smc/af_smc.c:664 Read of size 8 at addr ffff888050ff8528 by task syz-executor.5/3622 CPU: 0 PID: 3622 Comm: syz-executor.5 Not tainted 5.17.0-rc3-syzkaller-00157-g6605cc67ca18 #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 smc_fback_error_report+0x96/0xa0 net/smc/af_smc.c:664 sk_error_report+0x35/0x310 net/core/sock.c:340 tcp_write_err net/ipv4/tcp_timer.c:71 [inline] tcp_write_timeout net/ipv4/tcp_timer.c:276 [inline] tcp_retransmit_timer+0x20c2/0x3320 net/ipv4/tcp_timer.c:512 tcp_write_timer_handler+0x5e6/0xbc0 net/ipv4/tcp_timer.c:622 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:642 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:trace_lock_acquire include/trace/events/lock.h:13 [inline] RIP: 0010:lock_acquire+0x43d/0x510 kernel/locking/lockdep.c:5610 Code: f7 fe ff 5e 5f 65 ff 0d 51 11 a5 7e 0f 85 63 fc ff ff e8 d5 e6 a2 ff e9 59 fc ff ff 65 ff 05 3a 11 a5 7e 48 8b 05 93 1f 22 0c ce e3 05 00 85 c0 74 17 65 ff 0d 23 11 a5 7e 0f 85 78 fc ff ff RSP: 0018:ffffc9000286fb68 EFLAGS: 00000283 RAX: 0000000000000000 RBX: 1ffff9200050df6f RCX: ffffffff815d5b08 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d93c9d0 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8d93c9d7 R10: fffffbfff1b2793a R11: 000000000000003f R12: 0000000000000002 R13: 0000000000000000 R14: ffffffff8bb83c20 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:694 [inline] percpu_ref_get_many include/linux/percpu-refcount.h:202 [inline] percpu_ref_get include/linux/percpu-refcount.h:222 [inline] obj_cgroup_get include/linux/memcontrol.h:779 [inline] memcg_slab_post_alloc_hook+0x155/0x450 mm/slab.h:523 slab_post_alloc_hook mm/slab.h:739 [inline] slab_alloc_node mm/slub.c:3230 [inline] slab_alloc mm/slub.c:3238 [inline] kmem_cache_alloc+0x15c/0x3a0 mm/slub.c:3243 kmem_cache_zalloc include/linux/slab.h:705 [inline] __alloc_file+0x21/0x280 fs/file_table.c:134 alloc_empty_file+0x6d/0x170 fs/file_table.c:183 alloc_file+0x59/0x590 fs/file_table.c:225 alloc_file_pseudo+0x165/0x250 fs/file_table.c:265 sock_alloc_file+0x4f/0x190 net/socket.c:463 sock_map_fd net/socket.c:487 [inline] __sys_socket+0x13d/0x200 net/socket.c:1565 __do_sys_socket net/socket.c:1570 [inline] __se_sys_socket net/socket.c:1568 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1568 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: 0033:0x7ff01f3bc6d7 Code: f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 29 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:00007ffea4adf198 EFLAGS: 00000206 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 00007ffea4adf900 RCX: 00007ff01f3bc6d7 RDX: 0000000000000006 RSI: 0000000000000001 RDI: 0000000000000002 RBP: 0000000000000003 R08: 0000000000000000 R09: 00007ffea4adf710 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000032 R13: 000000000010dd9a R14: 0000000000000003 R15: 00007ffea4adf940 Allocated by task 16650: 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 sk_prot_alloc+0x5f/0x290 net/core/sock.c:1917 sk_alloc+0x32/0xa80 net/core/sock.c:1976 inet_create net/ipv4/af_inet.c:319 [inline] inet_create+0x395/0xea0 net/ipv4/af_inet.c:245 __sock_create+0x353/0x790 net/socket.c:1468 sock_create net/socket.c:1519 [inline] __sys_socket+0xef/0x200 net/socket.c:1561 __do_sys_socket net/socket.c:1570 [inline] __se_sys_socket net/socket.c:1568 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1568 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 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 __call_rcu kernel/rcu/tree.c:3026 [inline] call_rcu+0xb1/0x740 kernel/rcu/tree.c:3106 sk_destruct+0x102/0x180 net/core/sock.c:2061 __sk_free+0xef/0x3d0 net/core/sock.c:2074 sock_wfree+0x129/0x240 net/core/sock.c:2304 skb_release_head_state+0x9f/0x2a0 net/core/skbuff.c:729 skb_release_all net/core/skbuff.c:740 [inline] __kfree_skb net/core/skbuff.c:756 [inline] kfree_skb_reason net/core/skbuff.c:776 [inline] kfree_skb_reason+0xff/0x400 net/core/skbuff.c:770 neigh_invalidate+0x20d/0x560 net/core/neighbour.c:1024 neigh_timer_handler+0xd47/0x10e0 net/core/neighbour.c:1111 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 The buggy address belongs to the object at ffff888050ff8000 which belongs to the cache UDP-Lite of size 1728 The buggy address is located 1320 bytes inside of 1728-byte region [ffff888050ff8000, ffff888050ff86c0) The buggy address belongs to the page: page:ffffea000143fe00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888050ffc880 pfn:0x50ff8 head:ffffea000143fe00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88804ea5c801 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea000179bc00 dead000000000002 ffff888015deedc0 raw: ffff888050ffc880 0000000080110000 00000001ffffffff ffff88804ea5c801 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 11630, ts 1004764550954, free_ts 1004310785557 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 sk_prot_alloc+0x5f/0x290 net/core/sock.c:1917 sk_alloc+0x32/0xa80 net/core/sock.c:1976 inet_create net/ipv4/af_inet.c:319 [inline] inet_create+0x395/0xea0 net/ipv4/af_inet.c:245 __sock_create+0x353/0x790 net/socket.c:1468 sock_create net/socket.c:1519 [inline] __sys_socket+0xef/0x200 net/socket.c:1561 __do_sys_socket net/socket.c:1570 [inline] __se_sys_socket net/socket.c:1568 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1568 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 __unfreeze_partials+0x320/0x340 mm/slub.c:2536 qlink_free mm/kasan/quarantine.c:157 [inline] qlist_free_all+0x6d/0x160 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:446 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] taskstats_tgid_alloc kernel/taskstats.c:561 [inline] taskstats_exit+0x5c6/0xb40 kernel/taskstats.c:600 do_exit+0x8b1/0x2a30 kernel/exit.c:791 do_group_exit+0xd2/0x2f0 kernel/exit.c:935 get_signal+0x4b0/0x28c0 kernel/signal.c:2862 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae Memory state around the buggy address: ffff888050ff8400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888050ff8480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888050ff8500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888050ff8580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888050ff8600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: f7 fe idiv %esi 2: ff 5e 5f lcall *0x5f(%rsi) 5: 65 ff 0d 51 11 a5 7e decl %gs:0x7ea51151(%rip) # 0x7ea5115d c: 0f 85 63 fc ff ff jne 0xfffffc75 12: e8 d5 e6 a2 ff callq 0xffa2e6ec 17: e9 59 fc ff ff jmpq 0xfffffc75 1c: 65 ff 05 3a 11 a5 7e incl %gs:0x7ea5113a(%rip) # 0x7ea5115d 23: 48 8b 05 93 1f 22 0c mov 0xc221f93(%rip),%rax # 0xc221fbd * 2a: e8 ce e3 05 00 callq 0x5e3fd <-- trapping instruction 2f: 85 c0 test %eax,%eax 31: 74 17 je 0x4a 33: 65 ff 0d 23 11 a5 7e decl %gs:0x7ea51123(%rip) # 0x7ea5115d 3a: 0f 85 78 fc ff ff jne 0xfffffcb8