================================================================== BUG: KASAN: slab-use-after-free in hci_sock_get_cookie+0x4a/0x50 net/bluetooth/hci_sock.c:96 Read of size 4 at addr ffff888051cf85c0 by task syz.2.486/7853 CPU: 0 UID: 0 PID: 7853 Comm: syz.2.486 Not tainted 6.15.0-rc5-syzkaller-00136-g4d64321c4f6f #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xb4/0x290 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 hci_sock_get_cookie+0x4a/0x50 net/bluetooth/hci_sock.c:96 mgmt_cmd_status+0x1b5/0x4c0 net/bluetooth/mgmt_util.c:149 cmd_status_rsp net/bluetooth/mgmt.c:1464 [inline] cmd_complete_rsp+0x10d/0x1a0 net/bluetooth/mgmt.c:1484 mgmt_pending_foreach+0xc9/0x120 net/bluetooth/mgmt_util.c:242 __mgmt_power_off+0x15f/0x340 net/bluetooth/mgmt.c:9432 hci_dev_close_sync+0x754/0x1330 net/bluetooth/hci_sync.c:5221 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline] hci_dev_close+0x106/0x200 net/bluetooth/hci_core.c:508 sock_do_ioctl+0xd9/0x300 net/socket.c:1190 sock_ioctl+0x576/0x790 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f7b9bb8e969 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:00007f7b9ca51038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f7b9bdb5fa0 RCX: 00007f7b9bb8e969 RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000006 RBP: 00007f7b9bc10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f7b9bdb5fa0 R15: 00007ffcb8daf848 Allocated by task 6396: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4339 kmalloc_noprof include/linux/slab.h:909 [inline] sk_prot_alloc+0xe7/0x220 net/core/sock.c:2198 sk_alloc+0x3a/0x370 net/core/sock.c:2254 bt_sock_alloc+0x3b/0x310 net/bluetooth/af_bluetooth.c:148 hci_sock_create+0xa3/0x190 net/bluetooth/hci_sock.c:2202 bt_sock_create+0x160/0x240 net/bluetooth/af_bluetooth.c:132 __sock_create+0x4b0/0x9f0 net/socket.c:1541 sock_create net/socket.c:1599 [inline] __sys_socket_create net/socket.c:1636 [inline] __sys_socket+0xd7/0x1b0 net/socket.c:1683 __do_sys_socket net/socket.c:1697 [inline] __se_sys_socket net/socket.c:1695 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1695 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 7854: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2380 [inline] slab_free mm/slub.c:4642 [inline] kfree+0x193/0x440 mm/slub.c:4841 sk_prot_free net/core/sock.c:2237 [inline] __sk_destruct+0x4e1/0x660 net/core/sock.c:2332 sock_put include/net/sock.h:1944 [inline] mgmt_pending_free net/bluetooth/mgmt_util.c:290 [inline] mgmt_pending_remove+0x141/0x1a0 net/bluetooth/mgmt_util.c:298 mgmt_pending_foreach+0xc9/0x120 net/bluetooth/mgmt_util.c:242 mgmt_index_removed+0x10d/0x2f0 net/bluetooth/mgmt.c:9365 hci_sock_bind+0xbe9/0x1000 net/bluetooth/hci_sock.c:1307 __sys_bind_socket net/socket.c:1810 [inline] __sys_bind+0x2c3/0x3e0 net/socket.c:1841 __do_sys_bind net/socket.c:1846 [inline] __se_sys_bind net/socket.c:1844 [inline] __x64_sys_bind+0x7a/0x90 net/socket.c:1844 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888051cf8000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1472 bytes inside of freed 2048-byte region [ffff888051cf8000, ffff888051cf8800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x51cf8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801a042000 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801a042000 dead000000000100 dead000000000122 head: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001473e01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 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 5833, tgid 5833 (syz-executor), ts 91746943750, free_ts 27268831271 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1718 prep_new_page mm/page_alloc.c:1726 [inline] get_page_from_freelist+0x21ce/0x22b0 mm/page_alloc.c:3688 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2450 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2618 new_slab mm/slub.c:2672 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3858 __slab_alloc mm/slub.c:3948 [inline] __slab_alloc_node mm/slub.c:4023 [inline] slab_alloc_node mm/slub.c:4184 [inline] __kmalloc_cache_noprof+0x296/0x3d0 mm/slub.c:4353 kmalloc_noprof include/linux/slab.h:905 [inline] rtnl_newlink+0xed/0x1c70 net/core/rtnetlink.c:3965 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6955 netlink_rcv_skb+0x219/0x490 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 __sys_sendto+0x3bd/0x520 net/socket.c:2180 __do_sys_sendto net/socket.c:2187 [inline] __se_sys_sendto net/socket.c:2183 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2183 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0xb0e/0xcd0 mm/page_alloc.c:2725 __free_pages mm/page_alloc.c:5080 [inline] free_contig_range+0x159/0x440 mm/page_alloc.c:6936 destroy_args+0x86/0x460 mm/debug_vm_pgtable.c:1017 debug_vm_pgtable+0x3cf/0x410 mm/debug_vm_pgtable.c:1397 do_one_initcall+0x233/0x820 init/main.c:1257 do_initcall_level+0x137/0x1f0 init/main.c:1319 do_initcalls+0x69/0xd0 init/main.c:1335 kernel_init_freeable+0x3d9/0x570 init/main.c:1567 kernel_init+0x1d/0x1d0 init/main.c:1457 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff888051cf8480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888051cf8500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888051cf8580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888051cf8600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888051cf8680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================