Hello, syzbot found the following issue on: HEAD commit: be3ca57cfb77 Merge tag 'media/v6.7-1' of git://git.kernel... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1256c787680000 kernel config: https://syzkaller.appspot.com/x/.config?x=1ffa1cec3b40f3ce dashboard link: https://syzkaller.appspot.com/bug?extid=c23a22651335aa864a7a 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: https://storage.googleapis.com/syzbot-assets/09ea6e07e1d4/disk-be3ca57c.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/acd288df0801/vmlinux-be3ca57c.xz kernel image: https://storage.googleapis.com/syzbot-assets/40e81640103b/bzImage-be3ca57c.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+c23a22651335aa864a7a@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-use-after-free in l2cap_connect+0x10a5/0x1280 net/bluetooth/l2cap_core.c:4145 Read of size 8 at addr ffff88802a57b800 by task kworker/u5:7/5111 CPU: 0 PID: 5111 Comm: kworker/u5:7 Not tainted 6.6.0-syzkaller-15029-gbe3ca57cfb77 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Workqueue: hci5 hci_rx_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 l2cap_connect+0x10a5/0x1280 net/bluetooth/l2cap_core.c:4145 l2cap_connect_req net/bluetooth/l2cap_core.c:4287 [inline] l2cap_bredr_sig_cmd net/bluetooth/l2cap_core.c:5738 [inline] l2cap_sig_channel net/bluetooth/l2cap_core.c:6523 [inline] l2cap_recv_frame+0x3074/0x9440 net/bluetooth/l2cap_core.c:7802 l2cap_recv_acldata+0xa3d/0xbf0 net/bluetooth/l2cap_core.c:8520 hci_acldata_packet net/bluetooth/hci_core.c:3875 [inline] hci_rx_work+0xaa7/0x1610 net/bluetooth/hci_core.c:4110 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 </TASK> Allocated by task 50: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] l2cap_conn_add.part.0+0x60/0xdf0 net/bluetooth/l2cap_core.c:7845 l2cap_conn_add net/bluetooth/l2cap_core.c:71 [inline] l2cap_connect_cfm+0x424/0xfb0 net/bluetooth/l2cap_core.c:8242 hci_connect_cfm include/net/bluetooth/hci_core.h:1959 [inline] hci_remote_features_evt+0x565/0xa70 net/bluetooth/hci_event.c:3765 hci_event_func net/bluetooth/hci_event.c:7677 [inline] hci_event_packet+0x9d3/0x1160 net/bluetooth/hci_event.c:7729 hci_rx_work+0x2c4/0x1610 net/bluetooth/hci_core.c:4105 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Freed by task 50: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:522 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x15b/0x1b0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826 slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0xc0/0x180 mm/slub.c:3822 l2cap_conn_free net/bluetooth/l2cap_core.c:1949 [inline] kref_put include/linux/kref.h:65 [inline] l2cap_conn_put net/bluetooth/l2cap_core.c:1961 [inline] l2cap_conn_del+0x592/0x740 net/bluetooth/l2cap_core.c:1941 l2cap_connect_cfm+0xa10/0xfb0 net/bluetooth/l2cap_core.c:8238 hci_connect_cfm include/net/bluetooth/hci_core.h:1959 [inline] hci_conn_failed+0x1c3/0x370 net/bluetooth/hci_conn.c:1283 hci_abort_conn_sync+0x758/0xb50 net/bluetooth/hci_sync.c:5424 abort_conn_sync+0x187/0x390 net/bluetooth/hci_conn.c:2957 hci_cmd_sync_work+0x1a4/0x410 net/bluetooth/hci_sync.c:306 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 insert_work+0x38/0x230 kernel/workqueue.c:1647 __queue_work+0x5d0/0x1050 kernel/workqueue.c:1799 call_timer_fn+0x193/0x580 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1746 [inline] __run_timers+0x585/0xb10 kernel/time/timer.c:2022 run_timer_softirq+0x58/0xd0 kernel/time/timer.c:2035 __do_softirq+0x21a/0x968 kernel/softirq.c:553 Second to last potentially related work creation: kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:492 insert_work+0x38/0x230 kernel/workqueue.c:1647 __queue_work+0xb77/0x1050 kernel/workqueue.c:1803 queue_work_on+0xed/0x110 kernel/workqueue.c:1834 queue_work include/linux/workqueue.h:562 [inline] l2cap_conn_ready net/bluetooth/l2cap_core.c:1779 [inline] l2cap_connect_cfm+0x9f3/0xfb0 net/bluetooth/l2cap_core.c:8283 hci_connect_cfm include/net/bluetooth/hci_core.h:1959 [inline] hci_remote_features_evt+0x565/0xa70 net/bluetooth/hci_event.c:3765 hci_event_func net/bluetooth/hci_event.c:7677 [inline] hci_event_packet+0x9d3/0x1160 net/bluetooth/hci_event.c:7729 hci_rx_work+0x2c4/0x1610 net/bluetooth/hci_core.c:4105 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 The buggy address belongs to the object at ffff88802a57b800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 0 bytes inside of freed 1024-byte region [ffff88802a57b800, ffff88802a57bc00) The buggy address belongs to the physical page: page:ffffea0000a95e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a578 head:ffffea0000a95e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888013041dc0 ffffea00006f5200 dead000000000002 raw: 0000000000000000 0000000000100010 00000001ffffffff 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 29439741396, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1544 [inline] get_page_from_freelist+0xa25/0x36c0 mm/page_alloc.c:3312 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4568 alloc_pages_mpol+0x258/0x5f0 mm/mempolicy.c:2133 alloc_slab_page mm/slub.c:1870 [inline] allocate_slab+0x251/0x380 mm/slub.c:2017 new_slab mm/slub.c:2070 [inline] ___slab_alloc+0x8c7/0x1580 mm/slub.c:3223 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322 __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x131/0x310 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc_node_track_caller+0x50/0x100 mm/slab_common.c:1027 __do_krealloc mm/slab_common.c:1395 [inline] krealloc+0x5d/0x100 mm/slab_common.c:1428 add_sysfs_param+0xca/0x960 kernel/params.c:652 kernel_add_sysfs_param kernel/params.c:813 [inline] param_sysfs_builtin kernel/params.c:852 [inline] param_sysfs_builtin_init+0x2ca/0x450 kernel/params.c:986 do_one_initcall+0x11c/0x640 init/main.c:1236 do_initcall_level init/main.c:1298 [inline] do_initcalls init/main.c:1314 [inline] do_basic_setup init/main.c:1333 [inline] kernel_init_freeable+0x5c2/0x900 init/main.c:1551 kernel_init+0x1c/0x2a0 init/main.c:1441 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 page_owner free stack trace missing Memory state around the buggy address: ffff88802a57b700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802a57b780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802a57b800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802a57b880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802a57b900: 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
