================================================================== BUG: KASAN: slab-use-after-free in msft_opcode_get+0x6d/0x80 drivers/bluetooth/hci_vhci.c:222 Read of size 2 at addr ffff88807c9a7232 by task syz.7.6728/21394 CPU: 1 UID: 0 PID: 21394 Comm: syz.7.6728 Not tainted 6.13.0-syzkaller-09760-g69e858e0b8b2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 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:378 [inline] print_report+0xc3/0x620 mm/kasan/report.c:489 kasan_report+0xd9/0x110 mm/kasan/report.c:602 msft_opcode_get+0x6d/0x80 drivers/bluetooth/hci_vhci.c:222 simple_attr_read+0x169/0x300 fs/libfs.c:1334 debugfs_attr_read+0x76/0xa0 fs/debugfs/file.c:530 full_proxy_read+0x13c/0x200 fs/debugfs/file.c:389 vfs_read+0x1df/0xbf0 fs/read_write.c:563 ksys_read+0x12b/0x250 fs/read_write.c:708 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 RIP: 0033:0x7ff82bb8cda9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff82c952038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007ff82bda5fa0 RCX: 00007ff82bb8cda9 RDX: 000000000000ffff RSI: 0000000020006740 RDI: 0000000000000003 RBP: 00007ff82bc0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff82bda5fa0 R15: 00007ffdb20f1678 Allocated by task 1110: 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_node_track_caller_noprof+0x21d/0x520 mm/slub.c:4313 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609 pskb_expand_head+0x236/0x1170 net/core/skbuff.c:2275 __skb_cow include/linux/skbuff.h:3769 [inline] skb_cow_head include/linux/skbuff.h:3803 [inline] batadv_skb_head_push+0xf5/0x290 net/batman-adv/soft-interface.c:72 batadv_send_skb_packet+0x115/0x770 net/batman-adv/send.c:86 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:392 [inline] batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:420 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x70a/0x8d0 net/batman-adv/bat_iv_ogm.c:1700 process_one_work+0x958/0x1b30 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 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 Freed by task 1110: 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 skb_kfree_head net/core/skbuff.c:1086 [inline] skb_free_head+0x108/0x1d0 net/core/skbuff.c:1098 skb_release_data+0x560/0x730 net/core/skbuff.c:1125 skb_release_all net/core/skbuff.c:1190 [inline] __kfree_skb net/core/skbuff.c:1204 [inline] sk_skb_reason_drop+0x129/0x1a0 net/core/skbuff.c:1242 kfree_skb_reason include/linux/skbuff.h:1271 [inline] __netif_receive_skb_core.constprop.0+0x575/0x4330 net/core/dev.c:5802 __netif_receive_skb_one_core+0xb1/0x1e0 net/core/dev.c:5826 __netif_receive_skb+0x1d/0x160 net/core/dev.c:5941 process_backlog+0x443/0x15f0 net/core/dev.c:6289 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:7106 napi_poll net/core/dev.c:7175 [inline] net_rx_action+0xa94/0x1010 net/core/dev.c:7297 handle_softirqs+0x213/0x8f0 kernel/softirq.c:561 do_softirq kernel/softirq.c:462 [inline] do_softirq+0xb2/0xf0 kernel/softirq.c:449 __local_bh_enable_ip+0x100/0x120 kernel/softirq.c:389 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:919 [inline] __dev_queue_xmit+0x8b0/0x43e0 net/core/dev.c:4611 dev_queue_xmit include/linux/netdevice.h:3305 [inline] batadv_send_skb_packet+0x588/0x770 net/batman-adv/send.c:108 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:392 [inline] batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:420 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x70a/0x8d0 net/batman-adv/bat_iv_ogm.c:1700 process_one_work+0x958/0x1b30 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 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 The buggy address belongs to the object at ffff88807c9a7000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 562 bytes inside of freed 1024-byte region [ffff88807c9a7000, ffff88807c9a7400) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7c9a0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b041dc0 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b041dc0 0000000000000000 dead000000000001 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001f26801 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 5842, tgid 5842 (syz-executor), ts 90895695746, free_ts 90727639697 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+0xbfa/0x1600 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+0x2f0/0x520 mm/slub.c:4300 kmalloc_node_noprof include/linux/slab.h:928 [inline] qdisc_alloc+0xbb/0xc50 net/sched/sch_generic.c:947 qdisc_create_dflt+0x73/0x430 net/sched/sch_generic.c:1009 attach_one_default_qdisc net/sched/sch_generic.c:1175 [inline] netdev_for_each_tx_queue include/linux/netdevice.h:2590 [inline] attach_default_qdiscs net/sched/sch_generic.c:1193 [inline] dev_activate+0x63a/0x12b0 net/sched/sch_generic.c:1252 __dev_open+0x3e4/0x540 net/core/dev.c:1613 __dev_change_flags+0x561/0x720 net/core/dev.c:9172 dev_change_flags+0x8f/0x160 net/core/dev.c:9244 do_setlink.constprop.0+0x17b9/0x3f20 net/core/rtnetlink.c:3118 rtnl_changelink net/core/rtnetlink.c:3732 [inline] __rtnl_newlink net/core/rtnetlink.c:3884 [inline] rtnl_newlink+0x131c/0x1d70 net/core/rtnetlink.c:4021 page last free pid 5837 tgid 5837 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 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] kmem_cache_alloc_node_noprof+0x1ca/0x3b0 mm/slub.c:4216 __alloc_skb+0x2b3/0x380 net/core/skbuff.c:668 alloc_skb include/linux/skbuff.h:1331 [inline] nlmsg_new include/net/netlink.h:1018 [inline] netlink_ack+0x164/0xb20 net/netlink/af_netlink.c:2480 netlink_rcv_skb+0x327/0x410 net/netlink/af_netlink.c:2549 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:713 [inline] __sock_sendmsg net/socket.c:728 [inline] __sys_sendto+0x488/0x4f0 net/socket.c:2182 __do_sys_sendto net/socket.c:2189 [inline] __se_sys_sendto net/socket.c:2185 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2185 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 Memory state around the buggy address: ffff88807c9a7100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c9a7180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807c9a7200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807c9a7280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807c9a7300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================