Hello, syzbot found the following issue on: HEAD commit: 1b66c114d161 Merge tag 'nfsd-6.4-1' of git://git.kernel.or.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=157d87ce280000 kernel config: https://syzkaller.appspot.com/x/.config?x=94af80bb8ddd23c4 dashboard link: https://syzkaller.appspot.com/bug?extid=21835970af93643f25a2 compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/f5d99e318272/disk-1b66c114.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/2cdf457bc2a6/vmlinux-1b66c114.xz kernel image: https://storage.googleapis.com/syzbot-assets/a5d135c04826/bzImage-1b66c114.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+21835970af93643f25a2@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline] BUG: KASAN: slab-use-after-free in atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:575 [inline] BUG: KASAN: slab-use-after-free in hci_conn_drop+0x34/0x2c0 include/net/bluetooth/hci_core.h:1418 Write of size 4 at addr ffff8880406a6010 by task syz-executor.1/7637 CPU: 0 PID: 7637 Comm: syz-executor.1 Not tainted 6.4.0-rc2-syzkaller-00015-g1b66c114d161 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:351 [inline] print_report+0x163/0x540 mm/kasan/report.c:462 kasan_report+0x176/0x1b0 mm/kasan/report.c:572 kasan_check_range+0x283/0x290 mm/kasan/generic.c:187 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:575 [inline] hci_conn_drop+0x34/0x2c0 include/net/bluetooth/hci_core.h:1418 sco_chan_del+0xeb/0x1d0 net/bluetooth/sco.c:169 sco_sock_close net/bluetooth/sco.c:469 [inline] sco_sock_release+0xb3/0x320 net/bluetooth/sco.c:1267 __sock_release net/socket.c:653 [inline] sock_close+0xd1/0x230 net/socket.c:1397 __fput+0x3b7/0x890 fs/file_table.c:321 task_work_run+0x24a/0x300 kernel/task_work.c:179 get_signal+0x1606/0x17e0 kernel/signal.c:2650 arch_do_signal_or_restart+0x91/0x670 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:168 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:297 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f632188c169 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f63225fc168 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: fffffffffffffffc RBX: 00007f63219abf80 RCX: 00007f632188c169 RDX: 0000000000000008 RSI: 0000000020000100 RDI: 0000000000000004 RBP: 00007f63218e7ca1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff7261be3f R14: 00007f63225fc300 R15: 0000000000022000 </TASK> Allocated by task 7519: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:559 [inline] kzalloc include/linux/slab.h:680 [inline] hci_conn_add+0xc3/0x13a0 net/bluetooth/hci_conn.c:986 hci_connect_sco+0x8e/0x2b0 net/bluetooth/hci_conn.c:1663 sco_connect net/bluetooth/sco.c:264 [inline] sco_sock_connect+0x2b9/0x990 net/bluetooth/sco.c:610 __sys_connect_file net/socket.c:2003 [inline] __sys_connect+0x2cd/0x300 net/socket.c:2020 __do_sys_connect net/socket.c:2030 [inline] __se_sys_connect net/socket.c:2027 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2027 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 7110: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:521 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook mm/slub.c:1807 [inline] slab_free mm/slub.c:3786 [inline] __kmem_cache_free+0x264/0x3c0 mm/slub.c:3799 device_release+0x95/0x1c0 kobject_cleanup lib/kobject.c:683 [inline] kobject_release lib/kobject.c:714 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x228/0x470 lib/kobject.c:731 hci_conn_del+0x321/0x5a0 net/bluetooth/hci_conn.c:1162 hci_conn_unlink+0x1e1/0x320 net/bluetooth/hci_conn.c:1087 hci_conn_hash_flush+0x198/0x220 net/bluetooth/hci_conn.c:2479 hci_dev_close_sync+0xa35/0x1020 net/bluetooth/hci_sync.c:4941 hci_dev_do_close net/bluetooth/hci_core.c:554 [inline] hci_unregister_dev+0x1ca/0x480 net/bluetooth/hci_core.c:2703 vhci_release+0x83/0xd0 drivers/bluetooth/hci_vhci.c:669 __fput+0x3b7/0x890 fs/file_table.c:321 task_work_run+0x24a/0x300 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0x68f/0x2290 kernel/exit.c:871 do_group_exit+0x206/0x2c0 kernel/exit.c:1021 get_signal+0x1701/0x17e0 kernel/signal.c:2874 arch_do_signal_or_restart+0x91/0x670 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:168 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:297 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x3f/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:491 insert_work+0x54/0x3d0 kernel/workqueue.c:1365 __queue_work+0xb37/0xf10 kernel/workqueue.c:1526 queue_delayed_work_on+0x15a/0x260 kernel/workqueue.c:1710 sco_chan_del+0xeb/0x1d0 net/bluetooth/sco.c:169 sco_sock_close net/bluetooth/sco.c:469 [inline] sco_sock_release+0xb3/0x320 net/bluetooth/sco.c:1267 __sock_release net/socket.c:653 [inline] sock_close+0xd1/0x230 net/socket.c:1397 __fput+0x3b7/0x890 fs/file_table.c:321 task_work_run+0x24a/0x300 kernel/task_work.c:179 get_signal+0x1606/0x17e0 kernel/signal.c:2650 arch_do_signal_or_restart+0x91/0x670 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:168 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:297 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff8880406a6000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 16 bytes inside of freed 4096-byte region [ffff8880406a6000, ffff8880406a7000) The buggy address belongs to the physical page: page:ffffea000101a800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x406a0 head:ffffea000101a800 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000010200 ffff888012442140 ffffea0000a14a00 dead000000000002 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 0x1d2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 6060, tgid 6060 (udevadm), ts 248100761058, free_ts 248068222302 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1731 prep_new_page mm/page_alloc.c:1738 [inline] get_page_from_freelist+0x321c/0x33a0 mm/page_alloc.c:3502 __alloc_pages+0x255/0x670 mm/page_alloc.c:4768 alloc_slab_page+0x6a/0x160 mm/slub.c:1851 allocate_slab mm/slub.c:1998 [inline] new_slab+0x84/0x2f0 mm/slub.c:2051 ___slab_alloc+0xa85/0x10a0 mm/slub.c:3192 __slab_alloc mm/slub.c:3291 [inline] __slab_alloc_node mm/slub.c:3344 [inline] slab_alloc_node mm/slub.c:3441 [inline] __kmem_cache_alloc_node+0x1b8/0x290 mm/slub.c:3490 __do_kmalloc_node mm/slab_common.c:965 [inline] __kmalloc+0xa8/0x230 mm/slab_common.c:979 kmalloc include/linux/slab.h:563 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_check_open_permission+0x254/0x4e0 security/tomoyo/file.c:771 security_file_open+0x63/0xa0 security/security.c:2797 do_dentry_open+0x308/0x10f0 fs/open.c:907 do_open fs/namei.c:3636 [inline] path_openat+0x27b3/0x3170 fs/namei.c:3791 do_filp_open+0x234/0x490 fs/namei.c:3818 do_sys_openat2+0x13f/0x500 fs/open.c:1356 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x247/0x290 fs/open.c:1383 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1302 [inline] free_unref_page_prepare+0x903/0xa30 mm/page_alloc.c:2564 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2659 discard_slab mm/slub.c:2097 [inline] __unfreeze_partials+0x1b1/0x1f0 mm/slub.c:2636 put_cpu_partial+0x116/0x180 mm/slub.c:2712 qlist_free_all+0x22/0x60 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x14b/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x23/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook+0x68/0x3a0 mm/slab.h:711 slab_alloc_node mm/slub.c:3451 [inline] __kmem_cache_alloc_node+0x14c/0x290 mm/slub.c:3490 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1057 kmalloc include/linux/slab.h:559 [inline] kzalloc include/linux/slab.h:680 [inline] kernfs_iop_get_link+0x67/0x5a0 fs/kernfs/symlink.c:135 vfs_readlink+0x16e/0x400 fs/namei.c:5098 do_readlinkat+0x283/0x3b0 fs/stat.c:489 __do_sys_readlink fs/stat.c:510 [inline] __se_sys_readlink fs/stat.c:507 [inline] __x64_sys_readlink+0x7f/0x90 fs/stat.c:507 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff8880406a5f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880406a5f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880406a6000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880406a6080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880406a6100: 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 change 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
