Bluetooth: Unexpected start frame (len 1) ================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: slab-use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] BUG: KASAN: slab-use-after-free in refcount_read include/linux/refcount.h:136 [inline] BUG: KASAN: slab-use-after-free in skb_unref include/linux/skbuff.h:1227 [inline] BUG: KASAN: slab-use-after-free in __kfree_skb_reason net/core/skbuff.c:1116 [inline] BUG: KASAN: slab-use-after-free in kfree_skb_reason+0x41/0x390 net/core/skbuff.c:1143 Read of size 4 at addr ffff88802c37aea4 by task kworker/u5:5/5105 CPU: 1 PID: 5105 Comm: kworker/u5:5 Not tainted 6.8.0-rc6-syzkaller-00278-g58c806d867bf #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: hci4 hci_rx_work Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:377 [inline] print_report+0x167/0x540 mm/kasan/report.c:488 kasan_report+0x142/0x180 mm/kasan/report.c:601 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:68 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] refcount_read include/linux/refcount.h:136 [inline] skb_unref include/linux/skbuff.h:1227 [inline] __kfree_skb_reason net/core/skbuff.c:1116 [inline] kfree_skb_reason+0x41/0x390 net/core/skbuff.c:1143 kfree_skb include/linux/skbuff.h:1244 [inline] l2cap_recv_reset net/bluetooth/l2cap_core.c:8491 [inline] l2cap_recv_acldata+0x30c/0x1590 net/bluetooth/l2cap_core.c:8519 hci_acldata_packet net/bluetooth/hci_core.c:3876 [inline] hci_rx_work+0x50f/0xca0 net/bluetooth/hci_core.c:4111 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243 Allocated by task 5105: 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:3813 [inline] slab_alloc_node mm/slub.c:3860 [inline] kmem_cache_alloc_node+0x18f/0x380 mm/slub.c:3903 __alloc_skb+0x181/0x420 net/core/skbuff.c:641 alloc_skb include/linux/skbuff.h:1296 [inline] bt_skb_alloc include/net/bluetooth/bluetooth.h:487 [inline] l2cap_recv_frag net/bluetooth/l2cap_core.c:8438 [inline] l2cap_recv_acldata+0x52f/0x1590 net/bluetooth/l2cap_core.c:8528 hci_acldata_packet net/bluetooth/hci_core.c:3876 [inline] hci_rx_work+0x50f/0xca0 net/bluetooth/hci_core.c:4111 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243 Freed by task 5101: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:589 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2121 [inline] slab_free mm/slub.c:4299 [inline] kmem_cache_free+0x102/0x2a0 mm/slub.c:4363 kfree_skb include/linux/skbuff.h:1244 [inline] l2cap_conn_del+0x8c/0x680 net/bluetooth/l2cap_core.c:1899 l2cap_connect_cfm+0x121/0x1290 net/bluetooth/l2cap_core.c:8254 hci_connect_cfm include/net/bluetooth/hci_core.h:1986 [inline] hci_conn_failed+0x1f6/0x340 net/bluetooth/hci_conn.c:1289 hci_abort_conn_sync+0x583/0xde0 net/bluetooth/hci_sync.c:5359 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:306 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243 The buggy address belongs to the object at ffff88802c37adc0 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 228 bytes inside of freed 240-byte region [ffff88802c37adc0, ffff88802c37aeb0) The buggy address belongs to the physical page: page:ffffea0000b0de80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2c37a memcg:ffff88802c1fbb81 anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888018ac8640 0000000000000000 dead000000000001 raw: 0000000000000000 00000000000c000c 00000001ffffffff ffff88802c1fbb81 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 4535, tgid 4535 (udevd), ts 20681213689, free_ts 20667970896 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533 prep_new_page mm/page_alloc.c:1540 [inline] get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311 __alloc_pages+0x255/0x680 mm/page_alloc.c:4567 __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:2354 [inline] new_slab+0x84/0x2f0 mm/slub.c:2407 ___slab_alloc+0xd17/0x13e0 mm/slub.c:3540 __slab_alloc mm/slub.c:3625 [inline] __slab_alloc_node mm/slub.c:3678 [inline] slab_alloc_node mm/slub.c:3850 [inline] kmem_cache_alloc_node+0x245/0x380 mm/slub.c:3903 __alloc_skb+0x181/0x420 net/core/skbuff.c:641 alloc_skb include/linux/skbuff.h:1296 [inline] alloc_skb_with_frags+0xc3/0x780 net/core/skbuff.c:6394 sock_alloc_send_pskb+0x919/0xa60 net/core/sock.c:2783 unix_dgram_sendmsg+0x696/0x2200 net/unix/af_unix.c:1959 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 sock_write_iter+0x2dd/0x400 net/socket.c:1160 call_write_iter include/linux/fs.h:2087 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa81/0xcb0 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_64+0xf9/0x240 page last free pid 4533 tgid 4533 stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1140 [inline] free_unref_page_prepare+0x968/0xa90 mm/page_alloc.c:2346 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2486 rcu_do_batch kernel/rcu/tree.c:2190 [inline] rcu_core+0xd76/0x1810 kernel/rcu/tree.c:2465 __do_softirq+0x2bb/0x942 kernel/softirq.c:553 Memory state around the buggy address: ffff88802c37ad80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ffff88802c37ae00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802c37ae80: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ^ ffff88802c37af00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802c37af80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================