================================================================== BUG: KASAN: use-after-free in l2cap_sock_ready_cb+0xce/0x130 net/bluetooth/l2cap_sock.c:1659 Read of size 8 at addr ffff8880756a04c8 by task kworker/u5:0/146 CPU: 0 PID: 146 Comm: kworker/u5:0 Not tainted 5.15.175-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: hci0 hci_rx_work Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 print_address_description+0x63/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x16b/0x1c0 mm/kasan/report.c:451 l2cap_sock_ready_cb+0xce/0x130 net/bluetooth/l2cap_sock.c:1659 l2cap_chan_ready net/bluetooth/l2cap_core.c:1385 [inline] l2cap_le_start+0x4fa/0x1e60 net/bluetooth/l2cap_core.c:1497 l2cap_conn_ready net/bluetooth/l2cap_core.c:1766 [inline] l2cap_connect_cfm+0x72b/0x1270 net/bluetooth/l2cap_core.c:8289 hci_connect_cfm include/net/bluetooth/hci_core.h:1505 [inline] le_conn_complete_evt+0xd02/0x1500 net/bluetooth/hci_event.c:5432 hci_le_conn_complete_evt net/bluetooth/hci_event.c:5457 [inline] hci_le_meta_evt+0x28c/0x3f50 net/bluetooth/hci_event.c:6178 hci_event_packet+0xc41/0x1550 net/bluetooth/hci_event.c:6527 hci_rx_work+0x237/0xa10 net/bluetooth/hci_core.c:5160 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 6680: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc+0xba/0xf0 mm/kasan/common.c:513 kasan_kmalloc include/linux/kasan.h:264 [inline] __kmalloc+0x168/0x300 mm/slub.c:4407 kmalloc include/linux/slab.h:596 [inline] sk_prot_alloc+0xe0/0x200 net/core/sock.c:1863 sk_alloc+0x35/0x310 net/core/sock.c:1916 l2cap_sock_alloc+0x34/0x1f0 net/bluetooth/l2cap_sock.c:1861 l2cap_sock_create+0x10d/0x1c0 net/bluetooth/l2cap_sock.c:1908 bt_sock_create+0x159/0x220 net/bluetooth/af_bluetooth.c:130 __sock_create+0x460/0x8f0 net/socket.c:1486 sock_create net/socket.c:1542 [inline] __sys_socket+0x132/0x370 net/socket.c:1584 __do_sys_socket net/socket.c:1593 [inline] __se_sys_socket net/socket.c:1591 [inline] __x64_sys_socket+0x76/0x80 net/socket.c:1591 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 6680: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0xf1/0x270 mm/slub.c:4559 sk_prot_free net/core/sock.c:1899 [inline] __sk_destruct+0x58e/0x840 net/core/sock.c:1985 l2cap_sock_release+0x157/0x1d0 net/bluetooth/l2cap_sock.c:1429 __sock_release net/socket.c:649 [inline] sock_close+0xcd/0x230 net/socket.c:1336 __fput+0x3fe/0x8e0 fs/file_table.c:280 task_work_run+0x129/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff8880756a0000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1224 bytes inside of 2048-byte region [ffff8880756a0000, ffff8880756a0800) The buggy address belongs to the page: page:ffffea0001d5a800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x756a0 head:ffffea0001d5a800 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888017442000 raw: 0000000000000000 0000000000080008 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 0xd28c0(GFP_NOWAIT|__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4177, ts 54181426952, free_ts 54142488998 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x3b78/0x3d40 mm/page_alloc.c:4192 __alloc_pages+0x272/0x700 mm/page_alloc.c:5465 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xbb/0x4b0 mm/slub.c:1975 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] __kmalloc_node_track_caller+0x1f6/0x390 mm/slub.c:4958 kmalloc_reserve net/core/skbuff.c:356 [inline] pskb_expand_head+0x111/0x1130 net/core/skbuff.c:1709 netlink_trim+0x183/0x220 net/netlink/af_netlink.c:1293 netlink_broadcast_filtered+0x62/0x11a0 net/netlink/af_netlink.c:1498 netlink_broadcast net/netlink/af_netlink.c:1543 [inline] nlmsg_multicast include/net/netlink.h:1033 [inline] nlmsg_notify+0xf7/0x1b0 net/netlink/af_netlink.c:2532 rtnl_notify net/core/rtnetlink.c:759 [inline] rtmsg_ifinfo_send net/core/rtnetlink.c:3905 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3920 [inline] rtnetlink_event+0x155/0x1b0 net/core/rtnetlink.c:5698 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2018 [inline] call_netdevice_notifiers_extack net/core/dev.c:2030 [inline] call_netdevice_notifiers net/core/dev.c:2044 [inline] dev_set_mac_address+0x325/0x470 net/core/dev.c:9082 dev_set_mac_address_user+0x2d/0x50 net/core/dev.c:9096 do_setlink+0x7f0/0x3d80 net/core/rtnetlink.c:2731 __rtnl_newlink net/core/rtnetlink.c:3447 [inline] rtnl_newlink+0x17d6/0x2070 net/core/rtnetlink.c:3569 rtnetlink_rcv_msg+0x993/0xee0 net/core/rtnetlink.c:5647 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396 do_slab_free mm/slub.c:3487 [inline] ___cache_free+0xe3/0x100 mm/slub.c:3506 qlist_free_all+0x36/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x162/0x180 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x53/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3220 [inline] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc_trace+0xfb/0x290 mm/slub.c:3245 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] nsim_fib6_rt_create drivers/net/netdevsim/fib.c:545 [inline] nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:750 [inline] nsim_fib6_event drivers/net/netdevsim/fib.c:854 [inline] nsim_fib_event drivers/net/netdevsim/fib.c:887 [inline] nsim_fib_event_work+0x19be/0x4120 drivers/net/netdevsim/fib.c:1483 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 process_scheduled_works kernel/workqueue.c:2373 [inline] worker_thread+0xdcf/0x1280 kernel/workqueue.c:2459 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Memory state around the buggy address: ffff8880756a0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880756a0400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880756a0480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880756a0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880756a0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================