Hello, syzbot found the following issue on: HEAD commit: db87114dcf13 Merge tag 'x86_urgent_for_v6.12_rc4' of git:/.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=161d2a40580000 kernel config: https://syzkaller.appspot.com/x/.config?x=32b00a87124c18b7 dashboard link: https://syzkaller.appspot.com/bug?extid=1a89de7b76e603a5c5fb compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-db87114d.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/2a1e6237c364/vmlinux-db87114d.xz kernel image: https://storage.googleapis.com/syzbot-assets/6fc6ee2adb43/bzImage-db87114d.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+1a89de7b76e603a5c5fb@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-use-after-free in cmd_complete_rsp+0x1b3/0x1e0 net/bluetooth/mgmt.c:1463 Read of size 8 at addr ffff88802e045c40 by task syz.0.61/5584 CPU: 2 UID: 0 PID: 5584 Comm: syz.0.61 Not tainted 6.12.0-rc3-syzkaller-00454-gdb87114dcf13 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: <TASK> __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:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report+0xd9/0x110 mm/kasan/report.c:601 cmd_complete_rsp+0x1b3/0x1e0 net/bluetooth/mgmt.c:1463 mgmt_pending_foreach+0xdf/0x140 net/bluetooth/mgmt_util.c:259 __mgmt_power_off+0x12a/0x2c0 net/bluetooth/mgmt.c:9474 hci_dev_close_sync+0xc33/0x1110 net/bluetooth/hci_sync.c:5191 hci_dev_do_close+0x2e/0x90 net/bluetooth/hci_core.c:483 hci_dev_close+0x183/0x1e0 net/bluetooth/hci_core.c:508 hci_sock_ioctl+0x28c/0x880 net/bluetooth/hci_sock.c:1128 sock_do_ioctl+0x116/0x280 net/socket.c:1227 sock_ioctl+0x228/0x6c0 net/socket.c:1346 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18f/0x220 fs/ioctl.c:893 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: 0033:0x7fc90f77dff9 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:00007fc910494038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc90f935f80 RCX: 00007fc90f77dff9 RDX: 0000000000000000 RSI: 00000000400448ca RDI: 0000000000000004 RBP: 00007fc90f7f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc90f935f80 R15: 00007ffe69fe13d8 </TASK> Allocated by task 5549: 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 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] mgmt_pending_new+0x5b/0x290 net/bluetooth/mgmt_util.c:269 mgmt_pending_add+0x36/0x160 net/bluetooth/mgmt_util.c:296 start_discovery_internal+0x4a1/0x800 net/bluetooth/mgmt.c:5922 hci_mgmt_cmd net/bluetooth/hci_sock.c:1712 [inline] hci_sock_sendmsg+0x1528/0x25e0 net/bluetooth/hci_sock.c:1832 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg net/socket.c:744 [inline] sock_write_iter+0x4fe/0x5b0 net/socket.c:1165 new_sync_write fs/read_write.c:590 [inline] vfs_write+0x6b5/0x1140 fs/read_write.c:683 ksys_write+0x1fa/0x260 fs/read_write.c:736 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 Freed by task 5584: 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:579 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:230 [inline] slab_free_hook mm/slub.c:2342 [inline] slab_free mm/slub.c:4579 [inline] kfree+0x14f/0x4b0 mm/slub.c:4727 start_discovery_complete+0x146/0x220 net/bluetooth/mgmt.c:5860 _hci_cmd_sync_cancel_entry.constprop.0+0x6c/0x1d0 net/bluetooth/hci_sync.c:641 hci_cmd_sync_dequeue+0x178/0x1f0 net/bluetooth/hci_sync.c:886 cmd_complete_rsp+0x46/0x1e0 net/bluetooth/mgmt.c:1461 mgmt_pending_foreach+0xdf/0x140 net/bluetooth/mgmt_util.c:259 __mgmt_power_off+0x12a/0x2c0 net/bluetooth/mgmt.c:9474 hci_dev_close_sync+0xc33/0x1110 net/bluetooth/hci_sync.c:5191 hci_dev_do_close+0x2e/0x90 net/bluetooth/hci_core.c:483 hci_dev_close+0x183/0x1e0 net/bluetooth/hci_core.c:508 hci_sock_ioctl+0x28c/0x880 net/bluetooth/hci_sock.c:1128 sock_do_ioctl+0x116/0x280 net/socket.c:1227 sock_ioctl+0x228/0x6c0 net/socket.c:1346 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18f/0x220 fs/ioctl.c:893 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 The buggy address belongs to the object at ffff88802e045c00 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 64 bytes inside of freed 96-byte region [ffff88802e045c00, ffff88802e045c60) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802e045280 pfn:0x2e045 flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000200 ffff88801b042280 ffffea0000ce3590 ffffea000093fb50 raw: ffff88802e045280 0000000000200019 00000001f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5376, tgid 5376 (kworker/2:4), ts 38557960430, free_ts 38507952405 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x101e/0x3070 mm/page_alloc.c:3457 __alloc_pages_noprof+0x223/0x25a0 mm/page_alloc.c:4733 alloc_pages_mpol_noprof+0x2c9/0x610 mm/mempolicy.c:2265 alloc_slab_page mm/slub.c:2412 [inline] allocate_slab mm/slub.c:2578 [inline] new_slab+0x2ba/0x3f0 mm/slub.c:2631 ___slab_alloc+0xdac/0x1880 mm/slub.c:3818 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908 __slab_alloc_node mm/slub.c:3961 [inline] slab_alloc_node mm/slub.c:4122 [inline] __kmalloc_cache_noprof+0x2b4/0x300 mm/slub.c:4290 kmalloc_noprof include/linux/slab.h:878 [inline] dst_cow_metrics_generic+0x4c/0x1e0 net/core/dst.c:185 dst_metrics_write_ptr include/net/dst.h:133 [inline] dst_metric_set include/net/dst.h:194 [inline] icmp6_dst_alloc+0x370/0x490 net/ipv6/route.c:3288 mld_sendpack+0x5a9/0x11d0 net/ipv6/mcast.c:1808 mld_send_cr net/ipv6/mcast.c:2120 [inline] mld_ifc_work+0x740/0xca0 net/ipv6/mcast.c:2651 process_one_work+0x9c5/0x1ba0 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 page last free pid 24 tgid 24 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_page+0x5f4/0xdc0 mm/page_alloc.c:2638 __folio_put+0x30d/0x3d0 mm/swap.c:126 folio_put include/linux/mm.h:1478 [inline] free_page_and_swap_cache+0x249/0x2c0 mm/swap_state.c:308 __tlb_remove_table arch/x86/include/asm/tlb.h:34 [inline] __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x89/0xe0 mm/mmu_gather.c:282 rcu_do_batch kernel/rcu/tree.c:2567 [inline] rcu_core+0x79d/0x14d0 kernel/rcu/tree.c:2823 handle_softirqs+0x213/0x8f0 kernel/softirq.c:554 run_ksoftirqd kernel/softirq.c:927 [inline] run_ksoftirqd+0x3a/0x60 kernel/softirq.c:919 smpboot_thread_fn+0x661/0xa30 kernel/smpboot.c:164 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 Memory state around the buggy address: ffff88802e045b00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88802e045b80: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc >ffff88802e045c00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff88802e045c80: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc ffff88802e045d00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ================================================================== --- This report is generated by a bot. 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