================================================================== BUG: KASAN: slab-use-after-free in hci_cmd_work+0x5d0/0x7b0 net/bluetooth/hci_core.c:4174 Read of size 2 at addr ffff8880602bd8f8 by task kworker/u9:3/5832 CPU: 0 UID: 0 PID: 5832 Comm: kworker/u9:3 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: hci1 hci_cmd_work Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 hci_cmd_work+0x5d0/0x7b0 net/bluetooth/hci_core.c:4174 process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261 process_scheduled_works kernel/workqueue.c:3344 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Allocated by task 5147: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4948 [inline] slab_alloc_node mm/slub.c:5258 [inline] kmem_cache_alloc_node_noprof+0x43c/0x710 mm/slub.c:5310 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:664 alloc_skb include/linux/skbuff.h:1383 [inline] bt_skb_alloc include/net/bluetooth/bluetooth.h:510 [inline] hci_cmd_sync_alloc+0x3d/0x3b0 net/bluetooth/hci_sync.c:58 hci_cmd_sync_add net/bluetooth/hci_sync.c:99 [inline] __hci_cmd_sync_sk+0x1a7/0xc70 net/bluetooth/hci_sync.c:168 __hci_cmd_sync_status_sk net/bluetooth/hci_sync.c:263 [inline] __hci_cmd_sync_status net/bluetooth/hci_sync.c:287 [inline] hci_reset_sync+0x4a/0x140 net/bluetooth/hci_sync.c:3664 hci_init1_sync net/bluetooth/hci_sync.c:3750 [inline] hci_init_sync net/bluetooth/hci_sync.c:4874 [inline] hci_dev_init_sync net/bluetooth/hci_sync.c:5066 [inline] hci_dev_open_sync+0xec5/0x2dc0 net/bluetooth/hci_sync.c:5144 hci_dev_do_open net/bluetooth/hci_core.c:430 [inline] hci_power_on+0x1b4/0x720 net/bluetooth/hci_core.c:959 process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261 process_scheduled_works kernel/workqueue.c:3344 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Freed by task 5830: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6663 [inline] kmem_cache_free+0x197/0x640 mm/slub.c:6774 kfree_skb_reason include/linux/skbuff.h:1322 [inline] kfree_skb include/linux/skbuff.h:1331 [inline] vhci_read+0x49a/0x5b0 drivers/bluetooth/hci_vhci.c:593 vfs_read+0x200/0xa30 fs/read_write.c:570 ksys_read+0x145/0x250 fs/read_write.c:715 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880602bd8c0 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 56 bytes inside of freed 240-byte region [ffff8880602bd8c0, ffff8880602bd9b0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x602bd flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801dea18c0 dead000000000122 0000000000000000 raw: 0000000000000000 00000000000c000c 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5826, tgid 5826 (udevd), ts 89686668708, free_ts 89681982640 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3920 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5215 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3b0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xf56/0x1990 mm/slub.c:4651 __slab_alloc+0x65/0x100 mm/slub.c:4774 __slab_alloc_node mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:5246 [inline] kmem_cache_alloc_node_noprof+0x4ce/0x710 mm/slub.c:5310 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:664 netlink_sendmsg+0x5c6/0xb30 net/netlink/af_netlink.c:1869 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:746 ____sys_sendmsg+0x505/0x870 net/socket.c:2634 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2688 __sys_sendmsg net/socket.c:2720 [inline] __do_sys_sendmsg net/socket.c:2725 [inline] __se_sys_sendmsg net/socket.c:2723 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2723 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5824 tgid 5824 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2948 ___free_pages_bulk mm/kasan/shadow.c:333 [inline] __kasan_populate_vmalloc_do mm/kasan/shadow.c:385 [inline] __kasan_populate_vmalloc+0x137/0x1d0 mm/kasan/shadow.c:424 kasan_populate_vmalloc include/linux/kasan.h:579 [inline] alloc_vmap_area+0xdca/0x1500 mm/vmalloc.c:2124 __get_vm_area_node+0x1f8/0x300 mm/vmalloc.c:3220 __vmalloc_node_range_noprof+0x365/0x1640 mm/vmalloc.c:3981 __vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:4081 alloc_thread_stack_node kernel/fork.c:311 [inline] dup_task_struct+0x3d4/0x830 kernel/fork.c:880 copy_process+0x4ea/0x3930 kernel/fork.c:2011 kernel_clone+0x21e/0x850 kernel/fork.c:2609 __do_sys_clone3 kernel/fork.c:2911 [inline] __se_sys_clone3+0x256/0x2d0 kernel/fork.c:2890 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff8880602bd780: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880602bd800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc >ffff8880602bd880: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ^ ffff8880602bd900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880602bd980: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ==================================================================