================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3d86/0x54a0 kernel/locking/lockdep.c:4885 Read of size 8 at addr ffff8880161b20a0 by task kworker/0:4/8831 CPU: 0 PID: 8831 Comm: kworker/0:4 Not tainted 5.14.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events l2cap_chan_timeout Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:436 __lock_acquire+0x3d86/0x54a0 kernel/locking/lockdep.c:4885 lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:175 spin_lock_bh include/linux/spinlock.h:359 [inline] lock_sock_nested+0x40/0x120 net/core/sock.c:3183 l2cap_sock_teardown_cb+0xa1/0x660 net/bluetooth/l2cap_sock.c:1528 l2cap_chan_del+0xbc/0xa80 net/bluetooth/l2cap_core.c:622 l2cap_chan_close+0x1b9/0xaf0 net/bluetooth/l2cap_core.c:825 l2cap_chan_timeout+0x17e/0x2f0 net/bluetooth/l2cap_core.c:436 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 8856: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] ____kasan_kmalloc mm/kasan/common.c:472 [inline] __kasan_kmalloc+0xa4/0xd0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:596 [inline] sk_prot_alloc+0x110/0x290 net/core/sock.c:1822 sk_alloc+0x32/0xbc0 net/core/sock.c:1875 l2cap_sock_alloc.constprop.0+0x31/0x230 net/bluetooth/l2cap_sock.c:1813 l2cap_sock_create+0x123/0x1f0 net/bluetooth/l2cap_sock.c:1859 bt_sock_create+0x17c/0x340 net/bluetooth/af_bluetooth.c:130 __sock_create+0x353/0x790 net/socket.c:1461 sock_create net/socket.c:1512 [inline] __sys_socket+0xef/0x200 net/socket.c:1554 __do_sys_socket net/socket.c:1563 [inline] __se_sys_socket net/socket.c:1561 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1561 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 The buggy address belongs to the object at ffff8880161b2000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 160 bytes inside of 2048-byte region [ffff8880161b2000, ffff8880161b2800) The buggy address belongs to the page: page:ffffea0000586c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880161b7000 pfn:0x161b0 head:ffffea0000586c00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00008e8208 ffffea000084e808 ffff888010c42000 raw: ffff8880161b7000 0000000000080001 00000001ffffffff 0000000000000000 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 8470, ts 1583429111537, free_ts 1583157245659 prep_new_page mm/page_alloc.c:2436 [inline] get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4168 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5390 alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2244 alloc_slab_page mm/slub.c:1691 [inline] allocate_slab+0x32e/0x4b0 mm/slub.c:1831 new_slab mm/slub.c:1894 [inline] new_slab_objects mm/slub.c:2640 [inline] ___slab_alloc+0x473/0x7b0 mm/slub.c:2803 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2843 slab_alloc_node mm/slub.c:2925 [inline] __kmalloc_node_track_caller+0x2e3/0x360 mm/slub.c:4653 kmalloc_reserve net/core/skbuff.c:355 [inline] __alloc_skb+0xde/0x340 net/core/skbuff.c:426 alloc_skb include/linux/skbuff.h:1116 [inline] alloc_skb_with_frags+0x93/0x620 net/core/skbuff.c:6073 sock_alloc_send_pskb+0x783/0x910 net/core/sock.c:2475 mld_newpack+0x1df/0x770 net/ipv6/mcast.c:1756 add_grhead+0x265/0x330 net/ipv6/mcast.c:1859 add_grec+0x1053/0x14e0 net/ipv6/mcast.c:1997 mld_send_initial_cr.part.0+0xf6/0x230 net/ipv6/mcast.c:2244 mld_send_initial_cr net/ipv6/mcast.c:1232 [inline] ipv6_mc_dad_complete+0x1d0/0x690 net/ipv6/mcast.c:2255 addrconf_dad_completed+0xa20/0xd60 net/ipv6/addrconf.c:4183 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1346 [inline] free_pcp_prepare+0x2c5/0x780 mm/page_alloc.c:1397 free_unref_page_prepare mm/page_alloc.c:3332 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3411 unfreeze_partials+0x16c/0x1b0 mm/slub.c:2421 put_cpu_partial+0x13d/0x230 mm/slub.c:2457 qlink_free mm/kasan/quarantine.c:146 [inline] qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272 __kasan_slab_alloc+0x95/0xb0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook mm/slab.h:519 [inline] slab_alloc_node mm/slub.c:2959 [inline] slab_alloc mm/slub.c:2967 [inline] kmem_cache_alloc_trace+0x26d/0x3c0 mm/slub.c:2984 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] nsim_fib6_rt_create drivers/net/netdevsim/fib.c:544 [inline] nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:749 [inline] nsim_fib6_event drivers/net/netdevsim/fib.c:853 [inline] nsim_fib_event drivers/net/netdevsim/fib.c:886 [inline] nsim_fib_event_work+0xe43/0x2490 drivers/net/netdevsim/fib.c:1477 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276 process_scheduled_works kernel/workqueue.c:2338 [inline] worker_thread+0x85c/0x11f0 kernel/workqueue.c:2424 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff8880161b1f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880161b2000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880161b2080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880161b2100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880161b2180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================