================================================================== BUG: KASAN: slab-use-after-free in hci_cmd_timeout+0x1d9/0x1e0 net/bluetooth/hci_core.c:1522 Read of size 2 at addr ffff88802005f7b8 by task kworker/u9:4/5093 CPU: 0 PID: 5093 Comm: kworker/u9:4 Not tainted 6.9.0-syzkaller-05151-g1b294a1f3561 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: hci0 hci_cmd_timeout Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 hci_cmd_timeout+0x1d9/0x1e0 net/bluetooth/hci_core.c:1522 process_one_work kernel/workqueue.c:3267 [inline] process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3348 worker_thread+0x86d/0xd70 kernel/workqueue.c:3429 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 5093: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3871 [inline] slab_alloc_node mm/slub.c:3918 [inline] kmem_cache_alloc+0x174/0x350 mm/slub.c:3925 skb_clone+0x20c/0x390 net/core/skbuff.c:2052 hci_send_cmd_sync net/bluetooth/hci_core.c:4123 [inline] hci_cmd_work+0x29e/0x670 net/bluetooth/hci_core.c:4143 process_one_work kernel/workqueue.c:3267 [inline] process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3348 worker_thread+0x86d/0xd70 kernel/workqueue.c:3429 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 The buggy address belongs to the object at ffff88802005f780 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 56 bytes inside of freed 240-byte region [ffff88802005f780, ffff88802005f870) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2005f flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888018ede780 ffffea00018968c0 dead000000000004 raw: 0000000000000000 00000000000c000c 00000001ffffffff 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 0x152820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 6090, tgid 5067 (syz-fuzzer), ts 577478958654, free_ts 577475820517 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2190 allocate_slab mm/slub.c:2353 [inline] new_slab+0x84/0x2f0 mm/slub.c:2406 ___slab_alloc+0xb07/0x12e0 mm/slub.c:3592 __slab_alloc mm/slub.c:3682 [inline] __slab_alloc_node mm/slub.c:3735 [inline] slab_alloc_node mm/slub.c:3908 [inline] kmem_cache_alloc+0x252/0x350 mm/slub.c:3925 skb_clone+0x20c/0x390 net/core/skbuff.c:2052 dev_queue_xmit_nit+0x419/0xc10 net/core/dev.c:2311 xmit_one net/core/dev.c:3574 [inline] dev_hard_start_xmit+0x15f/0x7e0 net/core/dev.c:3594 sch_direct_xmit+0x2b6/0x5f0 net/sched/sch_generic.c:343 __dev_xmit_skb net/core/dev.c:3807 [inline] __dev_queue_xmit+0x1a24/0x3d30 net/core/dev.c:4359 dev_queue_xmit include/linux/netdevice.h:3095 [inline] neigh_hh_output include/net/neighbour.h:526 [inline] neigh_output include/net/neighbour.h:540 [inline] ip_finish_output2+0xd41/0x1380 net/ipv4/ip_output.c:235 ip_local_out net/ipv4/ip_output.c:129 [inline] __ip_queue_xmit+0x118c/0x1b70 net/ipv4/ip_output.c:535 __tcp_transmit_skb+0x2557/0x3b80 net/ipv4/tcp_output.c:1466 tcp_transmit_skb net/ipv4/tcp_output.c:1484 [inline] tcp_write_xmit+0x18b3/0x69d0 net/ipv4/tcp_output.c:2829 page last free pid 15046 tgid 15044 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1141 [inline] free_unref_page_prepare+0x97b/0xaa0 mm/page_alloc.c:2347 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487 tlb_batch_list_free mm/mmu_gather.c:159 [inline] tlb_finish_mmu+0x11f/0x200 mm/mmu_gather.c:468 exit_mmap+0x4bb/0xd60 mm/mmap.c:3282 __mmput+0x115/0x3c0 kernel/fork.c:1346 exit_mm+0x220/0x310 kernel/exit.c:569 do_exit+0x99e/0x27e0 kernel/exit.c:865 do_group_exit+0x207/0x2c0 kernel/exit.c:1027 get_signal+0x16a1/0x1740 kernel/signal.c:2911 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x102/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88802005f680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802005f700: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc >ffff88802005f780: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802005f800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff88802005f880: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ==================================================================