================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: slab-use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] BUG: KASAN: slab-use-after-free in refcount_read include/linux/refcount.h:136 [inline] BUG: KASAN: slab-use-after-free in skb_unref include/linux/skbuff.h:1222 [inline] BUG: KASAN: slab-use-after-free in __kfree_skb_reason net/core/skbuff.c:1195 [inline] BUG: KASAN: slab-use-after-free in kfree_skb_reason+0x36/0x210 net/core/skbuff.c:1222 Read of size 4 at addr ffff88801f12c364 by task syz-executor/6487 CPU: 1 PID: 6487 Comm: syz-executor Not tainted 6.10.0-rc6-syzkaller-00067-g8a9c6c40432e #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report+0xd9/0x110 mm/kasan/report.c:601 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:68 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] refcount_read include/linux/refcount.h:136 [inline] skb_unref include/linux/skbuff.h:1222 [inline] __kfree_skb_reason net/core/skbuff.c:1195 [inline] kfree_skb_reason+0x36/0x210 net/core/skbuff.c:1222 kfree_skb include/linux/skbuff.h:1257 [inline] __hci_req_sync+0x61d/0x980 net/bluetooth/hci_request.c:184 hci_req_sync+0x97/0xd0 net/bluetooth/hci_request.c:206 hci_dev_cmd+0x634/0x960 net/bluetooth/hci_core.c:787 hci_sock_ioctl+0x4f3/0x880 net/bluetooth/hci_sock.c:1150 sock_do_ioctl+0x116/0x280 net/socket.c:1222 sock_ioctl+0x22e/0x6c0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8509b757db Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007fffd8c74ed0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f8509b757db RDX: 00007fffd8c74f48 RSI: 00000000400448dd RDI: 0000000000000003 RBP: 000055558349d4a8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000002 R13: 0000000000000002 R14: 0000000000000009 R15: 0000000000000009 Allocated by task 64: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3940 [inline] slab_alloc_node mm/slub.c:4002 [inline] kmem_cache_alloc_noprof+0x121/0x2f0 mm/slub.c:4009 skb_clone+0x190/0x3f0 net/core/skbuff.c:2052 hci_send_cmd_sync net/bluetooth/hci_core.c:4123 [inline] hci_cmd_work+0x66a/0x710 net/bluetooth/hci_core.c:4143 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3248 process_scheduled_works kernel/workqueue.c:3329 [inline] worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 64: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object+0xf7/0x160 mm/kasan/common.c:240 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2196 [inline] slab_free mm/slub.c:4438 [inline] kmem_cache_free+0x12f/0x3a0 mm/slub.c:4513 kfree_skbmem+0x10e/0x200 net/core/skbuff.c:1131 __kfree_skb net/core/skbuff.c:1188 [inline] kfree_skb_reason+0x138/0x210 net/core/skbuff.c:1223 kfree_skb include/linux/skbuff.h:1257 [inline] hci_req_sync_complete+0x16c/0x270 net/bluetooth/hci_request.c:109 hci_event_packet+0x963/0x1170 net/bluetooth/hci_event.c:7479 hci_rx_work+0x2c4/0x1610 net/bluetooth/hci_core.c:4074 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3248 process_scheduled_works kernel/workqueue.c:3329 [inline] worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 The buggy address belongs to the object at ffff88801f12c280 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 228 bytes inside of freed 240-byte region [ffff88801f12c280, ffff88801f12c370) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1f12c head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffefff(slab) raw: 00fff00000000040 ffff888019298780 ffffea0000a7c680 dead000000000003 raw: 0000000000000000 0000000000190019 00000001ffffefff 0000000000000000 head: 00fff00000000040 ffff888019298780 ffffea0000a7c680 dead000000000003 head: 0000000000000000 0000000000190019 00000001ffffefff 0000000000000000 head: 00fff00000000001 ffffea00007c4b01 ffffffffffffffff 0000000000000000 head: 0000000000000002 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 6170, tgid 6170 (syz-executor), ts 319322108245, free_ts 319303442348 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1473 prep_new_page mm/page_alloc.c:1481 [inline] get_page_from_freelist+0x1353/0x2e50 mm/page_alloc.c:3425 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4683 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page+0x56/0x110 mm/slub.c:2265 allocate_slab mm/slub.c:2428 [inline] new_slab+0x84/0x260 mm/slub.c:2481 ___slab_alloc+0xdac/0x1870 mm/slub.c:3667 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3757 __slab_alloc_node mm/slub.c:3810 [inline] slab_alloc_node mm/slub.c:3990 [inline] kmem_cache_alloc_node_noprof+0xed/0x310 mm/slub.c:4045 __alloc_skb+0x2b1/0x380 net/core/skbuff.c:656 alloc_skb include/linux/skbuff.h:1308 [inline] nlmsg_new include/net/netlink.h:1015 [inline] inet_netconf_notify_devconf+0x8b/0x1f0 net/ipv4/devinet.c:2133 __devinet_sysctl_register+0x223/0x360 net/ipv4/devinet.c:2608 devinet_sysctl_register net/ipv4/devinet.c:2642 [inline] devinet_sysctl_register+0x17b/0x200 net/ipv4/devinet.c:2632 inetdev_init+0x28b/0x580 net/ipv4/devinet.c:291 inetdev_event+0xd23/0x19b0 net/ipv4/devinet.c:1565 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1992 page last free pid 6170 tgid 6170 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1093 [inline] free_unref_page+0x64a/0xe40 mm/page_alloc.c:2588 mm_free_pgd kernel/fork.c:804 [inline] __mmdrop+0xd5/0x470 kernel/fork.c:920 mmdrop include/linux/sched/mm.h:55 [inline] mmdrop_sched include/linux/sched/mm.h:83 [inline] mmdrop_lazy_tlb_sched include/linux/sched/mm.h:110 [inline] finish_task_switch.isra.0+0x7af/0xcc0 kernel/sched/core.c:5307 context_switch kernel/sched/core.c:5411 [inline] __schedule+0xf1d/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894 rwsem_down_write_slowpath kernel/locking/rwsem.c:1178 [inline] __down_write_common+0x950/0x13f0 kernel/locking/rwsem.c:1306 kernfs_add_one+0xb1/0x520 fs/kernfs/dir.c:778 __kernfs_create_file+0x295/0x350 fs/kernfs/file.c:1063 sysfs_add_file_mode_ns+0x1ff/0x3b0 fs/sysfs/file.c:307 create_files fs/sysfs/group.c:76 [inline] internal_create_group+0x565/0xe50 fs/sysfs/group.c:180 internal_create_groups+0x9d/0x150 fs/sysfs/group.c:220 device_add_groups drivers/base/core.c:2826 [inline] device_add_attrs drivers/base/core.c:2901 [inline] device_add+0xf33/0x1a70 drivers/base/core.c:3633 netdev_register_kobject+0x187/0x3f0 net/core/net-sysfs.c:2136 register_netdevice+0x12ce/0x1cb0 net/core/dev.c:10375 lapbeth_new_device drivers/net/wan/lapbether.c:418 [inline] lapbeth_device_event+0x5b0/0xd40 drivers/net/wan/lapbether.c:460 Memory state around the buggy address: ffff88801f12c200: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ffff88801f12c280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88801f12c300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ^ ffff88801f12c380: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ffff88801f12c400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================