================================================================== BUG: KASAN: slab-use-after-free in force_devcd_write+0x31f/0x350 drivers/bluetooth/hci_vhci.c:327 Read of size 8 at addr ffff888033935000 by task syz.4.3217/16702 CPU: 0 UID: 0 PID: 16702 Comm: syz.4.3217 Not tainted 6.13.0-rc4-syzkaller-00012-g9b2ffa6148b1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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 force_devcd_write+0x31f/0x350 drivers/bluetooth/hci_vhci.c:327 full_proxy_write+0xfb/0x1b0 fs/debugfs/file.c:356 vfs_write+0x24c/0x1150 fs/read_write.c:677 ksys_write+0x12b/0x250 fs/read_write.c:731 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: 0033:0x7f7d5b585d29 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:00007f7d5c2e9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f7d5b776080 RCX: 00007f7d5b585d29 RDX: 000000000000000e RSI: 0000000000000000 RDI: 0000000000000008 RBP: 00007f7d5b601b08 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f7d5b776080 R15: 00007ffe1d910988 Allocated by task 11636: 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:4298 [inline] __kmalloc_node_track_caller_noprof+0x21d/0x520 mm/slub.c:4317 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609 __alloc_skb+0x164/0x380 net/core/skbuff.c:678 alloc_skb include/linux/skbuff.h:1323 [inline] nlmsg_new include/net/netlink.h:1018 [inline] inet6_rt_notify+0xc7/0x260 net/ipv6/route.c:6195 fib6_add_rt2node net/ipv6/ip6_fib.c:1259 [inline] fib6_add+0x251d/0x4b20 net/ipv6/ip6_fib.c:1488 __ip6_ins_rt net/ipv6/route.c:1317 [inline] ip6_route_add+0x8d/0x1c0 net/ipv6/route.c:3857 addrconf_prefix_route+0x2fe/0x510 net/ipv6/addrconf.c:2486 addrconf_add_linklocal+0x32a/0x620 net/ipv6/addrconf.c:3338 addrconf_addr_gen+0x37b/0x3d0 net/ipv6/addrconf.c:3467 addrconf_dev_config net/ipv6/addrconf.c:3513 [inline] addrconf_init_auto_addrs+0x446/0x820 net/ipv6/addrconf.c:3591 addrconf_notify+0x6e2/0x19c0 net/ipv6/addrconf.c:3764 notifier_call_chain+0xb7/0x410 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1996 netdev_state_change net/core/dev.c:1378 [inline] netdev_state_change+0x115/0x150 net/core/dev.c:1371 linkwatch_do_dev+0x12b/0x160 net/core/link_watch.c:182 __linkwatch_run_queue+0x233/0x690 net/core/link_watch.c:239 linkwatch_event+0x8f/0xc0 net/core/link_watch.c:282 process_one_work+0x958/0x1b30 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 11636: 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:582 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:4613 [inline] kfree+0x14f/0x4b0 mm/slub.c:4761 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] consume_skb net/core/skbuff.c:1436 [inline] consume_skb+0xbf/0x100 net/core/skbuff.c:1430 netlink_broadcast_filtered+0x3d5/0xef0 net/netlink/af_netlink.c:1532 nlmsg_multicast_filtered include/net/netlink.h:1128 [inline] nlmsg_multicast include/net/netlink.h:1147 [inline] nlmsg_notify+0x9e/0x220 net/netlink/af_netlink.c:2585 inet6_rt_notify+0x19b/0x260 net/ipv6/route.c:6207 fib6_add_rt2node net/ipv6/ip6_fib.c:1259 [inline] fib6_add+0x251d/0x4b20 net/ipv6/ip6_fib.c:1488 __ip6_ins_rt net/ipv6/route.c:1317 [inline] ip6_route_add+0x8d/0x1c0 net/ipv6/route.c:3857 addrconf_prefix_route+0x2fe/0x510 net/ipv6/addrconf.c:2486 addrconf_add_linklocal+0x32a/0x620 net/ipv6/addrconf.c:3338 addrconf_addr_gen+0x37b/0x3d0 net/ipv6/addrconf.c:3467 addrconf_dev_config net/ipv6/addrconf.c:3513 [inline] addrconf_init_auto_addrs+0x446/0x820 net/ipv6/addrconf.c:3591 addrconf_notify+0x6e2/0x19c0 net/ipv6/addrconf.c:3764 notifier_call_chain+0xb7/0x410 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1996 netdev_state_change net/core/dev.c:1378 [inline] netdev_state_change+0x115/0x150 net/core/dev.c:1371 linkwatch_do_dev+0x12b/0x160 net/core/link_watch.c:182 __linkwatch_run_queue+0x233/0x690 net/core/link_watch.c:239 linkwatch_event+0x8f/0xc0 net/core/link_watch.c:282 process_one_work+0x958/0x1b30 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 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 ffff888033935000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 0 bytes inside of freed 1024-byte region [ffff888033935000, ffff888033935400) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888033935000 pfn:0x33930 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 ffff88801ac41dc0 ffffea00017e7210 ffffea0001ec5810 raw: ffff888033935000 000000000010000c 00000001f5000000 0000000000000000 head: 00fff00000000240 ffff88801ac41dc0 ffffea00017e7210 ffffea0001ec5810 head: ffff888033935000 000000000010000c 00000001f5000000 0000000000000000 head: 00fff00000000003 ffffea0000ce4c01 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 1, tgid 1 (swapper/0), ts 18834405534, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1558 prep_new_page mm/page_alloc.c:1566 [inline] get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3476 __alloc_pages_noprof+0x223/0x25b0 mm/page_alloc.c:4753 alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2269 alloc_slab_page mm/slub.c:2423 [inline] allocate_slab mm/slub.c:2589 [inline] new_slab+0x2c9/0x410 mm/slub.c:2642 ___slab_alloc+0xce2/0x1650 mm/slub.c:3830 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3920 __slab_alloc_node mm/slub.c:3995 [inline] slab_alloc_node mm/slub.c:4156 [inline] __do_kmalloc_node mm/slub.c:4297 [inline] __kmalloc_node_track_caller_noprof+0x2ee/0x520 mm/slub.c:4317 __do_krealloc mm/slub.c:4824 [inline] krealloc_noprof+0x157/0x360 mm/slub.c:4877 add_sysfs_param+0xcb/0x930 kernel/params.c:654 kernel_add_sysfs_param kernel/params.c:817 [inline] param_sysfs_builtin kernel/params.c:856 [inline] param_sysfs_builtin_init+0x253/0x3c0 kernel/params.c:990 do_one_initcall+0x128/0x630 init/main.c:1266 do_initcall_level init/main.c:1328 [inline] do_initcalls init/main.c:1344 [inline] do_basic_setup init/main.c:1363 [inline] kernel_init_freeable+0x58f/0x8b0 init/main.c:1577 kernel_init+0x1c/0x2b0 init/main.c:1466 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 page_owner free stack trace missing Memory state around the buggy address: ffff888033934f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888033934f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888033935000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888033935080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888033935100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================