================================================================== BUG: KASAN: slab-use-after-free in l2cap_sock_ready_cb+0x16a/0x170 net/bluetooth/l2cap_sock.c:1671 Read of size 8 at addr ffff8880611d9188 by task kworker/u9:2/5821 CPU: 1 UID: 0 PID: 5821 Comm: kworker/u9:2 Not tainted 6.14.0-rc4-syzkaller-00278-gece144f151ac #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: hci4 hci_rx_work Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xc3/0x670 mm/kasan/report.c:521 kasan_report+0xd9/0x110 mm/kasan/report.c:634 l2cap_sock_ready_cb+0x16a/0x170 net/bluetooth/l2cap_sock.c:1671 l2cap_chan_ready net/bluetooth/l2cap_core.c:1246 [inline] l2cap_le_start+0x1ec/0xe40 net/bluetooth/l2cap_core.c:1375 l2cap_conn_ready net/bluetooth/l2cap_core.c:1627 [inline] l2cap_connect_cfm+0x99f/0xf10 net/bluetooth/l2cap_core.c:7245 hci_connect_cfm include/net/bluetooth/hci_core.h:2051 [inline] le_conn_complete_evt+0x168d/0x1da0 net/bluetooth/hci_event.c:5763 hci_le_conn_complete_evt+0x23c/0x370 net/bluetooth/hci_event.c:5789 hci_le_meta_evt+0x2e2/0x5d0 net/bluetooth/hci_event.c:7162 hci_event_func net/bluetooth/hci_event.c:7470 [inline] hci_event_packet+0x666/0x1180 net/bluetooth/hci_event.c:7525 hci_rx_work+0x2c5/0x16b0 net/bluetooth/hci_core.c:4015 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3400 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 11952: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4294 [inline] __kmalloc_noprof+0x21c/0x510 mm/slub.c:4306 kmalloc_noprof include/linux/slab.h:905 [inline] sk_prot_alloc+0x1a8/0x2a0 net/core/sock.c:2181 sk_alloc+0x36/0xc20 net/core/sock.c:2234 bt_sock_alloc+0x3b/0x3a0 net/bluetooth/af_bluetooth.c:148 l2cap_sock_alloc.constprop.0+0x33/0x1d0 net/bluetooth/l2cap_sock.c:1878 l2cap_sock_create+0x123/0x1f0 net/bluetooth/l2cap_sock.c:1920 bt_sock_create+0x182/0x350 net/bluetooth/af_bluetooth.c:132 __sock_create+0x335/0x8d0 net/socket.c:1548 sock_create net/socket.c:1606 [inline] __sys_socket_create net/socket.c:1643 [inline] __sys_socket+0x14f/0x260 net/socket.c:1690 __do_sys_socket net/socket.c:1704 [inline] __se_sys_socket net/socket.c:1702 [inline] __x64_sys_socket+0x72/0xb0 net/socket.c:1702 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 Freed by task 11951: 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:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2353 [inline] slab_free mm/slub.c:4609 [inline] kfree+0x2c4/0x4d0 mm/slub.c:4757 sk_prot_free net/core/sock.c:2217 [inline] __sk_destruct+0x5ef/0x6f0 net/core/sock.c:2312 sk_destruct+0xc2/0xf0 net/core/sock.c:2340 __sk_free+0xf4/0x3e0 net/core/sock.c:2351 sk_free+0x6a/0x90 net/core/sock.c:2362 sock_put include/net/sock.h:1914 [inline] l2cap_sock_kill net/bluetooth/l2cap_sock.c:1252 [inline] l2cap_sock_kill+0x171/0x2d0 net/bluetooth/l2cap_sock.c:1237 l2cap_sock_release+0x189/0x210 net/bluetooth/l2cap_sock.c:1422 __sock_release+0xb0/0x270 net/socket.c:647 sock_close+0x1c/0x30 net/socket.c:1398 __fput+0x3ff/0xb70 fs/file_table.c:464 task_work_run+0x14e/0x250 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880611d9000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 392 bytes inside of freed 2048-byte region [ffff8880611d9000, ffff8880611d9800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x611d8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b042000 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b042000 dead000000000100 dead000000000122 head: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001847601 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 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 5822, tgid 5822 (syz-executor), ts 55598113881, free_ts 13058889019 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x221/0x2470 mm/page_alloc.c:4739 alloc_pages_mpol+0x1fc/0x540 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2423 [inline] allocate_slab mm/slub.c:2587 [inline] new_slab+0x23d/0x330 mm/slub.c:2640 ___slab_alloc+0xc5d/0x1720 mm/slub.c:3826 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3916 __slab_alloc_node mm/slub.c:3991 [inline] slab_alloc_node mm/slub.c:4152 [inline] __do_kmalloc_node mm/slub.c:4293 [inline] __kmalloc_node_noprof+0x2f0/0x510 mm/slub.c:4300 __kvmalloc_node_noprof+0xad/0x1a0 mm/util.c:662 kvmalloc_array_node_noprof include/linux/slab.h:1063 [inline] __ptr_ring_init_queue_alloc_noprof include/linux/ptr_ring.h:471 [inline] ptr_ring_init_noprof include/linux/ptr_ring.h:489 [inline] page_pool_init net/core/page_pool.c:263 [inline] page_pool_create_percpu+0x34e/0xb20 net/core/page_pool.c:343 nsim_create_page_pool drivers/net/netdevsim/netdev.c:387 [inline] nsim_init_napi drivers/net/netdevsim/netdev.c:410 [inline] nsim_open+0x376/0x9e0 drivers/net/netdevsim/netdev.c:447 __dev_open+0x2d4/0x540 net/core/dev.c:1635 __dev_change_flags+0x561/0x720 net/core/dev.c:9254 dev_change_flags+0x8f/0x160 net/core/dev.c:9326 do_setlink.constprop.0+0x699/0x3f80 net/core/rtnetlink.c:3118 rtnl_changelink net/core/rtnetlink.c:3733 [inline] __rtnl_newlink net/core/rtnetlink.c:3885 [inline] rtnl_newlink+0x1306/0x1d60 net/core/rtnetlink.c:4022 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0x6db/0xfb0 mm/page_alloc.c:2660 free_contig_range+0x133/0x3f0 mm/page_alloc.c:6678 destroy_args+0x66f/0x830 mm/debug_vm_pgtable.c:1017 debug_vm_pgtable+0x130f/0x2d60 mm/debug_vm_pgtable.c:1397 do_one_initcall+0x128/0x700 init/main.c:1257 do_initcall_level init/main.c:1319 [inline] do_initcalls init/main.c:1335 [inline] do_basic_setup init/main.c:1354 [inline] kernel_init_freeable+0x5c7/0x900 init/main.c:1568 kernel_init+0x1c/0x2b0 init/main.c:1457 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Memory state around the buggy address: ffff8880611d9080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880611d9100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880611d9180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880611d9200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880611d9280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================