================================================================== BUG: KASAN: slab-use-after-free in hci_chan_del+0x3b/0x1b0 net/bluetooth/hci_conn.c:2853 Read of size 8 at addr ffff8880293cd318 by task khidpd_04580009/6759 CPU: 1 UID: 0 PID: 6759 Comm: khidpd_04580009 Not tainted 6.14.0-rc1-next-20250206-syzkaller #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+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 hci_chan_del+0x3b/0x1b0 net/bluetooth/hci_conn.c:2853 l2cap_conn_free net/bluetooth/l2cap_core.c:1816 [inline] kref_put include/linux/kref.h:65 [inline] l2cap_conn_put+0x70/0xe0 net/bluetooth/l2cap_core.c:1830 session_free net/bluetooth/hidp/core.c:989 [inline] kref_put include/linux/kref.h:65 [inline] hidp_session_put+0x1e7/0x220 net/bluetooth/hidp/core.c:996 hidp_session_thread+0x458/0x490 net/bluetooth/hidp/core.c:1305 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 5849: 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:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4339 kmalloc_noprof include/linux/slab.h:902 [inline] kzalloc_noprof include/linux/slab.h:1038 [inline] hci_chan_create+0xc8/0x310 net/bluetooth/hci_conn.c:2838 l2cap_conn_add+0x69/0x8e0 net/bluetooth/l2cap_core.c:6864 l2cap_connect_cfm+0x115/0x1090 net/bluetooth/l2cap_core.c:7247 hci_connect_cfm include/net/bluetooth/hci_core.h:2051 [inline] hci_remote_features_evt+0x68e/0xac0 net/bluetooth/hci_event.c:3726 hci_event_func net/bluetooth/hci_event.c:7473 [inline] hci_event_packet+0xac2/0x1540 net/bluetooth/hci_event.c:7525 hci_rx_work+0x3f3/0xdb0 net/bluetooth/hci_core.c:4015 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 5849: 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:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2367 [inline] slab_free mm/slub.c:4623 [inline] kfree+0x196/0x430 mm/slub.c:4816 hci_chan_list_flush net/bluetooth/hci_conn.c:2878 [inline] hci_conn_cleanup net/bluetooth/hci_conn.c:149 [inline] hci_conn_del+0x4b5/0xc40 net/bluetooth/hci_conn.c:1164 hci_conn_hash_flush+0x258/0x350 net/bluetooth/hci_conn.c:2699 hci_dev_close_sync+0xa42/0x11c0 net/bluetooth/hci_sync.c:5197 hci_dev_do_close net/bluetooth/hci_core.c:482 [inline] hci_error_reset+0x12c/0x3f0 net/bluetooth/hci_core.c:1015 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/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 ffff8880293cd300 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 24 bytes inside of freed 128-byte region [ffff8880293cd300, ffff8880293cd380) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x293cd ksm flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801ac41a00 ffffea0000cf96c0 dead000000000003 raw: 0000000000000000 0000000000100010 00000000f5000000 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 12, tgid 12 (kworker/u8:1), ts 108807571979, free_ts 108765589483 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1629 prep_new_page mm/page_alloc.c:1637 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3555 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4817 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2437 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2601 new_slab mm/slub.c:2654 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3840 __slab_alloc+0x58/0xa0 mm/slub.c:3930 __slab_alloc_node mm/slub.c:4005 [inline] slab_alloc_node mm/slub.c:4166 [inline] __kmalloc_cache_noprof+0x27b/0x390 mm/slub.c:4334 kmalloc_noprof include/linux/slab.h:902 [inline] __hw_addr_create net/core/dev_addr_lists.c:60 [inline] __hw_addr_add_ex+0x1a8/0x610 net/core/dev_addr_lists.c:118 __dev_mc_add net/core/dev_addr_lists.c:868 [inline] dev_mc_add+0xa3/0x110 net/core/dev_addr_lists.c:886 igmp6_group_added+0x1a4/0x710 net/ipv6/mcast.c:684 __ipv6_dev_mc_inc+0x8da/0xac0 net/ipv6/mcast.c:988 addrconf_join_solict net/ipv6/addrconf.c:2240 [inline] addrconf_dad_begin net/ipv6/addrconf.c:4095 [inline] addrconf_dad_work+0x44f/0x16a0 net/ipv6/addrconf.c:4223 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 page last free pid 5202 tgid 5202 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1205 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2738 discard_slab mm/slub.c:2698 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3167 put_cpu_partial+0x17c/0x250 mm/slub.c:3242 __slab_free+0x290/0x380 mm/slub.c:4493 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4129 [inline] slab_alloc_node mm/slub.c:4178 [inline] __do_kmalloc_node mm/slub.c:4307 [inline] __kmalloc_noprof+0x236/0x4c0 mm/slub.c:4320 kmalloc_noprof include/linux/slab.h:906 [inline] kernfs_fop_write_iter+0x15a/0x500 fs/kernfs/file.c:311 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xacf/0xd10 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 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 Memory state around the buggy address: ffff8880293cd200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880293cd280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880293cd300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880293cd380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880293cd400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================