================================================================== BUG: KASAN: slab-use-after-free in l2cap_conn_ready net/bluetooth/l2cap_core.c:1624 [inline] BUG: KASAN: slab-use-after-free in l2cap_connect_cfm+0x6d0/0x1130 net/bluetooth/l2cap_core.c:7305 Read of size 8 at addr ffff88802840b480 by task kworker/u9:4/5832 CPU: 1 UID: 0 PID: 5832 Comm: kworker/u9:4 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Workqueue: hci3 hci_rx_work Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xba/0x230 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 l2cap_conn_ready net/bluetooth/l2cap_core.c:1624 [inline] l2cap_connect_cfm+0x6d0/0x1130 net/bluetooth/l2cap_core.c:7305 hci_connect_cfm+0x95/0x140 include/net/bluetooth/hci_core.h:2139 le_conn_complete_evt+0xf65/0x1430 net/bluetooth/hci_event.c:5847 hci_le_conn_complete_evt+0x187/0x470 net/bluetooth/hci_event.c:5873 hci_event_func net/bluetooth/hci_event.c:7781 [inline] hci_event_packet+0x7af/0x12c0 net/bluetooth/hci_event.c:7838 hci_rx_work+0x3ee/0x1030 net/bluetooth/hci_core.c:4077 process_one_work+0x949/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9af/0xee0 kernel/workqueue.c:3443 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5832: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5244 kmalloc_noprof include/linux/slab.h:962 [inline] kzalloc_noprof include/linux/slab.h:1204 [inline] l2cap_chan_create+0x51/0x790 net/bluetooth/l2cap_core.c:445 l2cap_sock_alloc net/bluetooth/l2cap_sock.c:1924 [inline] l2cap_sock_new_connection_cb+0x182/0x2e0 net/bluetooth/l2cap_sock.c:1503 l2cap_connect_cfm+0x367/0x1130 net/bluetooth/l2cap_core.c:7288 hci_connect_cfm+0x95/0x140 include/net/bluetooth/hci_core.h:2139 le_conn_complete_evt+0xf65/0x1430 net/bluetooth/hci_event.c:5847 hci_le_conn_complete_evt+0x187/0x470 net/bluetooth/hci_event.c:5873 hci_event_func net/bluetooth/hci_event.c:7781 [inline] hci_event_packet+0x7af/0x12c0 net/bluetooth/hci_event.c:7838 hci_rx_work+0x3ee/0x1030 net/bluetooth/hci_core.c:4077 process_one_work+0x949/0x15a0 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0x9af/0xee0 kernel/workqueue.c:3443 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 8231: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2621 [inline] slab_free mm/slub.c:6026 [inline] kfree+0x1c1/0x610 mm/slub.c:6339 l2cap_sock_cleanup_listen+0xf0/0x440 net/bluetooth/l2cap_sock.c:1486 l2cap_sock_release+0x6a/0x230 net/bluetooth/l2cap_sock.c:1444 __sock_release+0xb9/0x250 net/socket.c:666 sock_close+0x1c/0x30 net/socket.c:1470 __fput+0x44f/0xa70 fs/file_table.c:468 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88802840b000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1152 bytes inside of freed 2048-byte region [ffff88802840b000, ffff88802840b800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802840c000 pfn:0x28408 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88801b027000 ffffea000163c010 ffff88801b025948 raw: ffff88802840c000 0000000000080006 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88801b027000 ffffea000163c010 ffff88801b025948 head: ffff88802840c000 0000000000080006 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0000a10201 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 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 1, tgid 1 (swapper/0), ts 8027659527, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1883 prep_new_page mm/page_alloc.c:1891 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3956 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5244 alloc_slab_page mm/slub.c:3189 [inline] allocate_slab+0x7b/0x660 mm/slub.c:3362 new_slab mm/slub.c:3420 [inline] refill_objects+0x33a/0x3d0 mm/slub.c:7028 refill_sheaf mm/slub.c:2738 [inline] __pcs_replace_empty_main+0x2b9/0x620 mm/slub.c:4483 alloc_from_pcs mm/slub.c:4586 [inline] slab_alloc_node mm/slub.c:4720 [inline] __do_kmalloc_node mm/slub.c:5123 [inline] __kmalloc_noprof+0x474/0x760 mm/slub.c:5136 kmalloc_noprof include/linux/slab.h:966 [inline] kmalloc_array_noprof include/linux/slab.h:1113 [inline] vp_request_msix_vectors drivers/virtio/virtio_pci_common.c:137 [inline] vp_find_vqs_msix+0x44e/0xd40 drivers/virtio/virtio_pci_common.c:417 vp_find_vqs+0x9c/0x790 drivers/virtio/virtio_pci_common.c:525 virtio_find_vqs include/linux/virtio_config.h:298 [inline] virtnet_find_vqs drivers/net/virtio_net.c:6429 [inline] init_vqs+0xadf/0x11d0 drivers/net/virtio_net.c:6513 virtnet_probe+0x2215/0x4870 drivers/net/virtio_net.c:6919 virtio_dev_probe+0xd93/0x1050 drivers/virtio/virtio.c:347 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x267/0xaf0 drivers/base/dd.c:661 __driver_probe_device+0x18c/0x320 drivers/base/dd.c:803 driver_probe_device+0x4f/0x240 drivers/base/dd.c:833 __driver_attach+0x3e7/0x710 drivers/base/dd.c:1227 page_owner free stack trace missing Memory state around the buggy address: ffff88802840b380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802840b400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802840b480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802840b500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802840b580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================