Hello, syzbot found the following issue on: HEAD commit: 4f82870119a4 Merge tag 'mm-hotfixes-stable-2023-10-24-09-4.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=11b1b5a3680000 kernel config: https://syzkaller.appspot.com/x/.config?x=7d1f30869bb78ec6 dashboard link: https://syzkaller.appspot.com/bug?extid=8e6467fa0a1a160c9bbb 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/cb40650f0163/disk-4f828701.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/a1249f360a01/vmlinux-4f828701.xz kernel image: https://storage.googleapis.com/syzbot-assets/9af85659ca91/bzImage-4f828701.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+8e6467fa0a1a160c9bbb@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-use-after-free in hci_conn_drop include/net/bluetooth/hci_core.h:1549 [inline] BUG: KASAN: slab-use-after-free in hci_conn_drop include/net/bluetooth/hci_core.h:1519 [inline] BUG: KASAN: slab-use-after-free in sco_chan_del+0x4bf/0x4f0 net/bluetooth/sco.c:171 Read of size 8 at addr ffff88807bd46a58 by task syz-executor.5/23800 CPU: 1 PID: 23800 Comm: syz-executor.5 Not tainted 6.6.0-rc7-syzkaller-00039-g4f82870119a4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 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 hci_conn_drop include/net/bluetooth/hci_core.h:1549 [inline] hci_conn_drop include/net/bluetooth/hci_core.h:1519 [inline] sco_chan_del+0x4bf/0x4f0 net/bluetooth/sco.c:171 __sco_sock_close+0xf2/0x690 net/bluetooth/sco.c:454 sco_sock_close net/bluetooth/sco.c:469 [inline] sco_sock_release+0x6f/0x2c0 net/bluetooth/sco.c:1246 __sock_release+0xae/0x260 net/socket.c:659 sock_close+0x1c/0x20 net/socket.c:1419 __fput+0x3f7/0xa70 fs/file_table.c:384 task_work_run+0x14d/0x240 kernel/task_work.c:180 get_signal+0x106f/0x2790 kernel/signal.c:2668 arch_do_signal_or_restart+0x90/0x7f0 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x60 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f150d47cae9 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:00007f150e1ff0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: fffffffffffffffc RBX: 00007f150d59c050 RCX: 00007f150d47cae9 RDX: 0000000000000008 RSI: 0000000020000000 RDI: 0000000000000004 RBP: 00007f150d4c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f150d59c050 R15: 00007ffc409e1338 </TASK> Allocated by task 23800: 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:599 [inline] kzalloc include/linux/slab.h:720 [inline] hci_conn_add+0xc2/0x17c0 net/bluetooth/hci_conn.c:957 hci_connect_sco+0x3a0/0xf80 net/bluetooth/hci_conn.c:1701 sco_connect net/bluetooth/sco.c:266 [inline] sco_sock_connect+0x2c7/0xa80 net/bluetooth/sco.c:591 __sys_connect_file+0x15b/0x1a0 net/socket.c:2050 __sys_connect+0x145/0x170 net/socket.c:2067 __do_sys_connect net/socket.c:2077 [inline] __se_sys_connect net/socket.c:2074 [inline] __x64_sys_connect+0x72/0xb0 net/socket.c:2074 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 19887: 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+0xb8/0x2f0 mm/slub.c:3822 device_release+0xa1/0x240 drivers/base/core.c:2484 kobject_cleanup lib/kobject.c:682 [inline] kobject_release lib/kobject.c:716 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1d0/0x440 lib/kobject.c:733 put_device+0x1f/0x30 drivers/base/core.c:3732 hci_conn_cleanup_child net/bluetooth/hci_conn.c:1065 [inline] hci_conn_unlink+0x71b/0x9e0 net/bluetooth/hci_conn.c:1092 hci_conn_del+0x59/0xd80 net/bluetooth/hci_conn.c:1118 hci_abort_conn_sync+0x573/0xe10 net/bluetooth/hci_sync.c:5428 abort_conn_sync+0x187/0x390 net/bluetooth/hci_conn.c:2910 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:304 The buggy address belongs to the object at ffff88807bd46000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 2648 bytes inside of freed 4096-byte region [ffff88807bd46000, ffff88807bd47000) The buggy address belongs to the physical page: page:ffffea0001ef5000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7bd40 head:ffffea0001ef5000 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888012c42140 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000040004 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 0x1d2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 21210, tgid 21210 (kworker/1:4), ts 1947372032238, free_ts 1947098144795 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0xee0/0x2f20 mm/page_alloc.c:3170 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4426 alloc_pages+0x1a9/0x270 mm/mempolicy.c:2299 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+0x131/0x340 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1025 [inline] __kmalloc_node_track_caller+0x50/0x100 mm/slab_common.c:1046 kmalloc_reserve+0xef/0x260 net/core/skbuff.c:581 __alloc_skb+0x12b/0x330 net/core/skbuff.c:650 alloc_skb include/linux/skbuff.h:1286 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x29e/0xc70 drivers/net/netdevsim/dev.c:850 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 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1136 [inline] free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2312 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2405 __unfreeze_partials+0x21d/0x240 mm/slub.c:2655 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook mm/slab.h:762 [inline] slab_alloc_node mm/slub.c:3478 [inline] __kmem_cache_alloc_node+0x195/0x340 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1025 [inline] __kmalloc+0x4f/0x100 mm/slab_common.c:1039 kmalloc_array include/linux/slab.h:636 [inline] kcalloc include/linux/slab.h:667 [inline] iter_file_splice_write+0x167/0xbf0 fs/splice.c:676 do_splice_from fs/splice.c:933 [inline] direct_splice_actor+0x118/0x180 fs/splice.c:1142 splice_direct_to_actor+0x347/0xa30 fs/splice.c:1088 do_splice_direct+0x1af/0x280 fs/splice.c:1194 do_sendfile+0xb88/0x1390 fs/read_write.c:1254 __do_sys_sendfile64 fs/read_write.c:1316 [inline] __se_sys_sendfile64 fs/read_write.c:1308 [inline] __x64_sys_sendfile64+0x155/0x220 fs/read_write.c:1308 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff88807bd46900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807bd46980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807bd46a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807bd46a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807bd46b00: 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 bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
