================================================================== BUG: KASAN: use-after-free in atomic_read /./include/asm-generic/atomic-instrumented.h:26 [inline] BUG: KASAN: use-after-free in refcount_inc_not_zero_checked+0x81/0x200 /lib/refcount.c:123 Read of size 4 at addr ffff8880640600c0 by task syz-executor.3/11348 CPU: 1 PID: 11348 Comm: syz-executor.3 Not tainted 5.2.0+ #62 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack /lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 /lib/dump_stack.c:113 print_address_description.cold+0xd4/0x306 /mm/kasan/report.c:351 __kasan_report.cold+0x1b/0x36 /mm/kasan/report.c:482 kasan_report+0x12/0x17 /mm/kasan/common.c:612 check_memory_region_inline /mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 /mm/kasan/generic.c:192 __kasan_check_read+0x11/0x20 /mm/kasan/common.c:92 atomic_read /./include/asm-generic/atomic-instrumented.h:26 [inline] refcount_inc_not_zero_checked+0x81/0x200 /lib/refcount.c:123 refcount_inc_checked+0x17/0x70 /lib/refcount.c:156 sock_hold /./include/net/sock.h:649 [inline] sk_add_node /./include/net/sock.h:701 [inline] nr_insert_socket+0x2d/0xe0 /net/netrom/af_netrom.c:137 nr_rx_frame+0x1605/0x1e73 /net/netrom/af_netrom.c:1023 nr_loopback_timer+0x7b/0x170 /net/netrom/nr_loopback.c:59 call_timer_fn+0x1ac/0x780 /kernel/time/timer.c:1322 expire_timers /kernel/time/timer.c:1366 [inline] __run_timers /kernel/time/timer.c:1685 [inline] __run_timers /kernel/time/timer.c:1653 [inline] run_timer_softirq+0x697/0x17a0 /kernel/time/timer.c:1698 __do_softirq+0x262/0x98c /kernel/softirq.c:292 invoke_softirq /kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 /kernel/softirq.c:413 exiting_irq /./arch/x86/include/asm/apic.h:537 [inline] smp_apic_timer_interrupt+0x1a3/0x610 /arch/x86/kernel/apic/apic.c:1095 apic_timer_interrupt+0xf/0x20 /arch/x86/entry/entry_64.S:828 RIP: 0010:unwind_next_frame+0xe/0x50 /arch/x86/kernel/unwind_frame.c:265 Code: 68 ff ff ff 4c 8b 8d 70 ff ff ff e9 b7 fb ff ff 66 90 66 2e 0f 1f 84 00 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 55 <48> c1 ea 03 48 89 e5 48 83 ec 08 0f b6 14 02 48 89 f8 83 e0 07 83 RSP: 0018:ffff888061fa70e8 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: ffffffff81617890 RCX: ffffc9000c5cc000 RDX: ffff888061fa70f8 RSI: ffffffff816179be RDI: ffff888061fa70f8 RBP: ffff888061fa7180 R08: ffff8880583ac280 R09: ffff888061fa7150 R10: ffff888061fa7120 R11: ffff888061fa7130 R12: ffff888061fa71b0 R13: 0000000000000000 R14: ffff8880583ac280 R15: ffff8880aa596540 stack_trace_save+0xac/0xe0 /kernel/stacktrace.c:123 save_stack+0x23/0x90 /mm/kasan/common.c:69 set_track /mm/kasan/common.c:77 [inline] __kasan_kmalloc /mm/kasan/common.c:487 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 /mm/kasan/common.c:460 kasan_slab_alloc+0xf/0x20 /mm/kasan/common.c:495 slab_post_alloc_hook /mm/slab.h:520 [inline] slab_alloc /mm/slab.c:3319 [inline] kmem_cache_alloc+0x121/0x710 /mm/slab.c:3483 kmem_cache_zalloc /./include/linux/slab.h:738 [inline] __kernfs_new_node+0xf0/0x6c0 /fs/kernfs/dir.c:631 kernfs_new_node+0x96/0x120 /fs/kernfs/dir.c:697 __kernfs_create_file+0x51/0x33b /fs/kernfs/file.c:1001 sysfs_add_file_mode_ns+0x222/0x560 /fs/sysfs/file.c:305 create_files /fs/sysfs/group.c:63 [inline] internal_create_group+0x359/0xc30 /fs/sysfs/group.c:148 internal_create_groups.part.0+0x90/0x140 /fs/sysfs/group.c:188 internal_create_groups /fs/sysfs/group.c:184 [inline] sysfs_create_groups+0x2a/0x50 /fs/sysfs/group.c:214 device_add_groups /drivers/base/core.c:1288 [inline] device_add_attrs /drivers/base/core.c:1447 [inline] device_add+0x8c7/0x17a0 /drivers/base/core.c:2080 netdev_register_kobject+0x183/0x3b0 /net/core/net-sysfs.c:1746 register_netdevice+0x875/0xf10 /net/core/dev.c:8723 register_vlan_dev+0x2f9/0x800 /net/8021q/vlan.c:176 register_vlan_device /net/8021q/vlan.c:277 [inline] vlan_ioctl_handler+0xbc0/0xf93 /net/8021q/vlan.c:623 sock_ioctl+0x518/0x790 /net/socket.c:1143 vfs_ioctl /fs/ioctl.c:46 [inline] file_ioctl /fs/ioctl.c:509 [inline] do_vfs_ioctl+0xdb6/0x13e0 /fs/ioctl.c:696 ksys_ioctl+0xab/0xd0 /fs/ioctl.c:713 __do_sys_ioctl /fs/ioctl.c:720 [inline] __se_sys_ioctl /fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 /fs/ioctl.c:718 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459819 Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ff239db0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459819 RDX: 0000000020000080 RSI: 0800000000008982 RDI: 0000000000000007 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff239db16d4 R13: 00000000004c0c29 R14: 00000000004d3ac0 R15: 00000000ffffffff Allocated by task 11348: save_stack+0x23/0x90 /mm/kasan/common.c:69 set_track /mm/kasan/common.c:77 [inline] __kasan_kmalloc /mm/kasan/common.c:487 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 /mm/kasan/common.c:460 kasan_kmalloc+0x9/0x10 /mm/kasan/common.c:501 __do_kmalloc /mm/slab.c:3655 [inline] __kmalloc+0x163/0x770 /mm/slab.c:3664 kmalloc /./include/linux/slab.h:557 [inline] sk_prot_alloc+0x23a/0x310 /net/core/sock.c:1603 sk_alloc+0x39/0xf70 /net/core/sock.c:1657 nr_make_new /net/netrom/af_netrom.c:476 [inline] nr_rx_frame+0x733/0x1e73 /net/netrom/af_netrom.c:959 nr_loopback_timer+0x7b/0x170 /net/netrom/nr_loopback.c:59 call_timer_fn+0x1ac/0x780 /kernel/time/timer.c:1322 expire_timers /kernel/time/timer.c:1366 [inline] __run_timers /kernel/time/timer.c:1685 [inline] __run_timers /kernel/time/timer.c:1653 [inline] run_timer_softirq+0x697/0x17a0 /kernel/time/timer.c:1698 __do_softirq+0x262/0x98c /kernel/softirq.c:292 Freed by task 11356: save_stack+0x23/0x90 /mm/kasan/common.c:69 set_track /mm/kasan/common.c:77 [inline] __kasan_slab_free+0x102/0x150 /mm/kasan/common.c:449 kasan_slab_free+0xe/0x10 /mm/kasan/common.c:457 __cache_free /mm/slab.c:3425 [inline] kfree+0x10a/0x2c0 /mm/slab.c:3756 sk_prot_free /net/core/sock.c:1640 [inline] __sk_destruct+0x4f7/0x6e0 /net/core/sock.c:1726 sk_destruct+0x86/0xa0 /net/core/sock.c:1734 __sk_free+0xfb/0x360 /net/core/sock.c:1745 sk_free+0x42/0x50 /net/core/sock.c:1756 sock_put /./include/net/sock.h:1725 [inline] sock_efree+0x61/0x80 /net/core/sock.c:2042 skb_release_head_state+0xeb/0x250 /net/core/skbuff.c:652 skb_release_all+0x16/0x60 /net/core/skbuff.c:663 __kfree_skb /net/core/skbuff.c:679 [inline] kfree_skb /net/core/skbuff.c:697 [inline] kfree_skb+0x101/0x3c0 /net/core/skbuff.c:691 nr_accept+0x56e/0x700 /net/netrom/af_netrom.c:819 __sys_accept4+0x34e/0x6a0 /net/socket.c:1750 __do_sys_accept4 /net/socket.c:1785 [inline] __se_sys_accept4 /net/socket.c:1782 [inline] __x64_sys_accept4+0x97/0xf0 /net/socket.c:1782 do_syscall_64+0xfd/0x6a0 /arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888064060040 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 128 bytes inside of 2048-byte region [ffff888064060040, ffff888064060840) The buggy address belongs to the page: page:ffffea0001901800 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea0001900088 ffffea0001901f08 ffff8880aa400e00 raw: 0000000000000000 ffff888064060040 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88806405ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888064060000: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff888064060080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888064060100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888064060180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================