Hello, syzbot found the following issue on: HEAD commit: 45403b12c29c ip_tunnel: Move stats allocation to core git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=12dd357a980000 kernel config: https://syzkaller.appspot.com/x/.config?x=ce6b8d38d53fa4e dashboard link: https://syzkaller.appspot.com/bug?extid=d047bdb99944f4429ce7 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/08e0ccb0d0c7/disk-45403b12.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/d8c2fb69ea08/vmlinux-45403b12.xz kernel image: https://storage.googleapis.com/syzbot-assets/f665a6962ffc/bzImage-45403b12.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+d047bdb99944f4429ce7@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-use-after-free in hci_sock_get_cookie+0x49/0x50 net/bluetooth/hci_sock.c:96 Read of size 4 at addr ffff888055333568 by task syz-executor.2/5954 CPU: 1 PID: 5954 Comm: syz-executor.2 Not tainted 6.10.0-rc2-syzkaller-00724-g45403b12c29c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: <TASK> __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_sock_get_cookie+0x49/0x50 net/bluetooth/hci_sock.c:96 mgmt_cmd_status+0x1be/0x4d0 net/bluetooth/mgmt_util.c:149 cmd_status_rsp net/bluetooth/mgmt.c:1451 [inline] cmd_complete_rsp+0xe7/0x150 net/bluetooth/mgmt.c:1466 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259 __mgmt_power_off+0x187/0x420 net/bluetooth/mgmt.c:9413 hci_dev_close_sync+0x587/0xf60 net/bluetooth/hci_sync.c:5058 hci_dev_do_close net/bluetooth/hci_core.c:556 [inline] hci_dev_close+0x112/0x210 net/bluetooth/hci_core.c:581 sock_do_ioctl+0x158/0x460 net/socket.c:1222 sock_ioctl+0x629/0x8e0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2334e7cea9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2335caa0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f2334fb3f80 RCX: 00007f2334e7cea9 RDX: 0000000000000000 RSI: 00000000400448ca RDI: 000000000000000d RBP: 00007f2334eebff4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f2334fb3f80 R15: 00007ffd57013a68 </TASK> Allocated by task 5225: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slub.c:4121 [inline] __kmalloc_noprof+0x1f9/0x400 mm/slub.c:4134 kmalloc_noprof include/linux/slab.h:664 [inline] sk_prot_alloc+0xe0/0x210 net/core/sock.c:2096 sk_alloc+0x38/0x370 net/core/sock.c:2149 bt_sock_alloc+0x3c/0x340 net/bluetooth/af_bluetooth.c:148 hci_sock_create+0xa1/0x190 net/bluetooth/hci_sock.c:2202 bt_sock_create+0x161/0x230 net/bluetooth/af_bluetooth.c:132 __sock_create+0x490/0x920 net/socket.c:1571 sock_create net/socket.c:1622 [inline] __sys_socket_create net/socket.c:1659 [inline] __sys_socket+0x150/0x3c0 net/socket.c:1706 __do_sys_socket net/socket.c:1720 [inline] __se_sys_socket net/socket.c:1718 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1718 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5962: 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:579 poison_slab_object+0xe0/0x150 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:2195 [inline] slab_free mm/slub.c:4436 [inline] kfree+0x149/0x360 mm/slub.c:4557 sk_prot_free net/core/sock.c:2132 [inline] __sk_destruct+0x476/0x5f0 net/core/sock.c:2224 sock_put include/net/sock.h:1879 [inline] mgmt_pending_free net/bluetooth/mgmt_util.c:307 [inline] mgmt_pending_remove+0x13e/0x1a0 net/bluetooth/mgmt_util.c:315 mgmt_pending_foreach+0xd1/0x130 net/bluetooth/mgmt_util.c:259 mgmt_index_removed+0xe6/0x340 net/bluetooth/mgmt.c:9346 hci_sock_bind+0xcc6/0x1140 net/bluetooth/hci_sock.c:1307 __sys_bind+0x23d/0x2f0 net/socket.c:1847 __do_sys_bind net/socket.c:1858 [inline] __se_sys_bind net/socket.c:1856 [inline] __x64_sys_bind+0x7a/0x90 net/socket.c:1856 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888055333000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1384 bytes inside of freed 2048-byte region [ffff888055333000, ffff888055333800) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x55330 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: 0xffffefff(slab) raw: 00fff00000000040 ffff888015042000 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000080008 00000001ffffefff 0000000000000000 head: 00fff00000000040 ffff888015042000 dead000000000100 dead000000000122 head: 0000000000000000 0000000000080008 00000001ffffefff 0000000000000000 head: 00fff00000000003 ffffea000154cc01 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4538, tgid 4538 (klogd), ts 83329536244, free_ts 22893428251 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1468 prep_new_page mm/page_alloc.c:1476 [inline] get_page_from_freelist+0x2e2d/0x2ee0 mm/page_alloc.c:3402 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4660 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page+0x5f/0x120 mm/slub.c:2264 allocate_slab+0x5a/0x2e0 mm/slub.c:2427 new_slab mm/slub.c:2480 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3666 __slab_alloc+0x58/0xa0 mm/slub.c:3756 __slab_alloc_node mm/slub.c:3809 [inline] slab_alloc_node mm/slub.c:3988 [inline] kmalloc_trace_noprof+0x1d5/0x2c0 mm/slub.c:4147 kmalloc_noprof include/linux/slab.h:660 [inline] syslog_print+0x121/0x9c0 kernel/printk/printk.c:1553 do_syslog+0x3bb/0x810 kernel/printk/printk.c:1731 __do_sys_syslog kernel/printk/printk.c:1823 [inline] __se_sys_syslog kernel/printk/printk.c:1821 [inline] __x64_sys_syslog+0x7c/0x90 kernel/printk/printk.c:1821 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f 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:1088 [inline] free_unref_page+0xd22/0xea0 mm/page_alloc.c:2565 free_contig_range+0x9e/0x160 mm/page_alloc.c:6619 destroy_args+0x8a/0x890 mm/debug_vm_pgtable.c:1038 debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1418 do_one_initcall+0x248/0x880 init/main.c:1267 do_initcall_level+0x157/0x210 init/main.c:1329 do_initcalls+0x3f/0x80 init/main.c:1345 kernel_init_freeable+0x435/0x5d0 init/main.c:1578 kernel_init+0x1d/0x2b0 init/main.c:1467 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Memory state around the buggy address: ffff888055333400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888055333480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888055333500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888055333580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888055333600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup