Hello, syzbot found the following issue on: HEAD commit: 2ccdd1b13c59 Linux 6.5-rc6 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16990d53a80000 kernel config: https://syzkaller.appspot.com/x/.config?x=9c37cc0e4fcc5f8d dashboard link: https://syzkaller.appspot.com/bug?extid=fb337a5ea8454f5f1e3f compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17ba5d53a80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14265373a80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/ecb74567efdf/disk-2ccdd1b1.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/347764e4bb8e/vmlinux-2ccdd1b1.xz kernel image: https://storage.googleapis.com/syzbot-assets/84f1d2de7e10/bzImage-2ccdd1b1.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/21e9fff65e06/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+fb337a5ea8454f5f1e3f@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task syz-executor415:5343 blocked for more than 143 seconds. Not tainted 6.5.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor415 state:D stack:25032 pid:5343 ppid:5095 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1873/0x48f0 kernel/sched/core.c:6710 schedule+0xc3/0x180 kernel/sched/core.c:6786 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845 rwsem_down_write_slowpath+0xedd/0x13a0 kernel/locking/rwsem.c:1178 __down_write_common+0x1aa/0x200 kernel/locking/rwsem.c:1306 do_remount fs/namespace.c:2879 [inline] path_mount+0xbdd/0xfa0 fs/namespace.c:3654 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount+0x2d9/0x3c0 fs/namespace.c:3861 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 RIP: 0033:0x7f917fa53c0a RSP: 002b:00007ffd6ff7f3a8 EFLAGS: 00000286 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f917fa53c0a RDX: 0000000020000180 RSI: 0000000020000100 RDI: 0000000000000000 RBP: 00007ffd6ff7f440 R08: 00007ffd6ff7f440 R09: 0000000000000000 R10: 0000000001a404ac R11: 0000000000000286 R12: 0000000020000100 R13: 0000000020000180 R14: 0000000000000000 R15: 0000000020003600 </TASK> INFO: task syz-executor415:5344 blocked for more than 143 seconds. Not tainted 6.5.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor415 state:D stack:25032 pid:5344 ppid:5089 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1873/0x48f0 kernel/sched/core.c:6710 schedule+0xc3/0x180 kernel/sched/core.c:6786 jfs_flush_journal+0x733/0xec0 fs/jfs/jfs_logmgr.c:1564 jfs_sync_fs+0x80/0xa0 fs/jfs/super.c:684 dquot_quota_sync+0xdb/0x490 fs/quota/dquot.c:704 iterate_supers+0x12b/0x1e0 fs/super.c:744 quota_sync_all fs/quota/quota.c:69 [inline] __do_sys_quotactl fs/quota/quota.c:938 [inline] __se_sys_quotactl+0x391/0xa30 fs/quota/quota.c:917 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 RIP: 0033:0x7f917fa525d9 RSP: 002b:00007ffd6ff7f588 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f917fa525d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101 RBP: 0000000000000000 R08: 0000000000005d70 R09: 00007ffd6ff7f5b8 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd6ff7f5b8 R13: 000000000000001f R14: 00007ffd6ff7f5f0 R15: 431bde82d7b634db </TASK> INFO: task syz-executor415:5345 blocked for more than 143 seconds. Not tainted 6.5.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor415 state:D stack:25032 pid:5345 ppid:5087 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1873/0x48f0 kernel/sched/core.c:6710 schedule+0xc3/0x180 kernel/sched/core.c:6786 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845 rwsem_down_read_slowpath+0x5f4/0x950 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1250 [inline] __down_read kernel/locking/rwsem.c:1263 [inline] down_read+0x9c/0x2f0 kernel/locking/rwsem.c:1522 iterate_supers+0xb0/0x1e0 fs/super.c:742 quota_sync_all fs/quota/quota.c:69 [inline] __do_sys_quotactl fs/quota/quota.c:938 [inline] __se_sys_quotactl+0x391/0xa30 fs/quota/quota.c:917 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 RIP: 0033:0x7f917fa525d9 RSP: 002b:00007ffd6ff7f588 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f917fa525d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101 RBP: 0000000000000000 R08: 0000000000005d70 R09: 00007ffd6ff7f5b8 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd6ff7f5b8 R13: 000000000000001d R14: 00007ffd6ff7f5f0 R15: 431bde82d7b634db </TASK> INFO: task syz-executor415:5346 blocked for more than 144 seconds. Not tainted 6.5.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor415 state:D stack:25032 pid:5346 ppid:5084 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1873/0x48f0 kernel/sched/core.c:6710 schedule+0xc3/0x180 kernel/sched/core.c:6786 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845 rwsem_down_read_slowpath+0x5f4/0x950 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1250 [inline] __down_read kernel/locking/rwsem.c:1263 [inline] down_read+0x9c/0x2f0 kernel/locking/rwsem.c:1522 iterate_supers+0xb0/0x1e0 fs/super.c:742 quota_sync_all fs/quota/quota.c:69 [inline] __do_sys_quotactl fs/quota/quota.c:938 [inline] __se_sys_quotactl+0x391/0xa30 fs/quota/quota.c:917 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 RIP: 0033:0x7f917fa525d9 RSP: 002b:00007ffd6ff7f588 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f917fa525d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101 RBP: 0000000000000000 R08: 0000000000005d70 R09: 00007ffd6ff7f5b8 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd6ff7f5b8 R13: 000000000000001d R14: 00007ffd6ff7f5f0 R15: 431bde82d7b634db </TASK> INFO: task syz-executor415:5347 blocked for more than 144 seconds. Not tainted 6.5.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor415 state:D stack:25032 pid:5347 ppid:5086 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1873/0x48f0 kernel/sched/core.c:6710 schedule+0xc3/0x180 kernel/sched/core.c:6786 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845 rwsem_down_read_slowpath+0x5f4/0x950 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1250 [inline] __down_read kernel/locking/rwsem.c:1263 [inline] down_read+0x9c/0x2f0 kernel/locking/rwsem.c:1522 iterate_supers+0xb0/0x1e0 fs/super.c:742 quota_sync_all fs/quota/quota.c:69 [inline] __do_sys_quotactl fs/quota/quota.c:938 [inline] __se_sys_quotactl+0x391/0xa30 fs/quota/quota.c:917 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 RIP: 0033:0x7f917fa525d9 RSP: 002b:00007ffd6ff7f588 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f917fa525d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101 RBP: 0000000000000000 R08: 0000000000005d70 R09: 00007ffd6ff7f5b8 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd6ff7f5b8 R13: 000000000000001e R14: 00007ffd6ff7f5f0 R15: 431bde82d7b634db </TASK> INFO: task syz-executor415:5348 blocked for more than 144 seconds. Not tainted 6.5.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor415 state:D stack:25384 pid:5348 ppid:5088 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1873/0x48f0 kernel/sched/core.c:6710 schedule+0xc3/0x180 kernel/sched/core.c:6786 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845 rwsem_down_read_slowpath+0x5f4/0x950 kernel/locking/rwsem.c:1086 __down_read_common kernel/locking/rwsem.c:1250 [inline] __down_read kernel/locking/rwsem.c:1263 [inline] down_read+0x9c/0x2f0 kernel/locking/rwsem.c:1522 iterate_supers+0xb0/0x1e0 fs/super.c:742 quota_sync_all fs/quota/quota.c:69 [inline] __do_sys_quotactl fs/quota/quota.c:938 [inline] __se_sys_quotactl+0x391/0xa30 fs/quota/quota.c:917 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 RIP: 0033:0x7f917fa525d9 RSP: 002b:00007ffd6ff7f588 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f917fa525d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101 RBP: 0000000000000000 R08: 0000000000005d70 R09: 00007ffd6ff7f5b8 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd6ff7f5b8 R13: 000000000000001e R14: 00007ffd6ff7f5f0 R15: 431bde82d7b634db </TASK> Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/13: #0: ffffffff8d3295b0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:522 1 lock held by rcu_tasks_trace/14: #0: ffffffff8d329970 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:522 1 lock held by khungtaskd/28: #0: ffffffff8d3293e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/4779: #0: ffff8880291c2098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900015b02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b1/0x1dc0 drivers/tty/n_tty.c:2187 2 locks held by kworker/u4:5/5177: #0: ffff8880b983bf98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 #1: ffff8880b98287c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x3a7/0x770 kernel/sched/psi.c:987 1 lock held by syz-executor415/5343: #0: ffff88807aef40e0 (&type->s_umount_key#65){++++}-{3:3}, at: do_remount fs/namespace.c:2879 [inline] #0: ffff88807aef40e0 (&type->s_umount_key#65){++++}-{3:3}, at: path_mount+0xbdd/0xfa0 fs/namespace.c:3654 1 lock held by syz-executor415/5344: #0: ffff88807aef40e0 (&type->s_umount_key#65){++++}-{3:3}, at: iterate_supers+0xb0/0x1e0 fs/super.c:742 1 lock held by syz-executor415/5345: #0: ffff88807aef40e0 (&type->s_umount_key#65){++++}-{3:3}, at: iterate_supers+0xb0/0x1e0 fs/super.c:742 1 lock held by syz-executor415/5346: #0: ffff88807aef40e0 (&type->s_umount_key#65){++++}-{3:3}, at: iterate_supers+0xb0/0x1e0 fs/super.c:742 1 lock held by syz-executor415/5347: #0: ffff88807aef40e0 (&type->s_umount_key#65){++++}-{3:3}, at: iterate_supers+0xb0/0x1e0 fs/super.c:742 1 lock held by syz-executor415/5348: #0: ffff88807aef40e0 (&type->s_umount_key#65){++++}-{3:3}, at: iterate_supers+0xb0/0x1e0 fs/super.c:742 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.5.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x498/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x187/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xec2/0xf00 kernel/hung_task.c:379 kthread+0x2b8/0x350 kernel/kthread.c:389 ret_from_fork+0x2e/0x60 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 </TASK> Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 41 Comm: kworker/u4:2 Not tainted 6.5.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Workqueue: bat_events batadv_mcast_mla_update RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:102 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline] RIP: 0010:unwind_next_frame+0x495/0x2390 arch/x86/kernel/unwind_orc.c:494 Code: 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 27 48 63 03 48 01 d8 48 8d 4b 04 4c 39 f8 4c 0f 46 e9 <48> 8d 43 fc 48 0f 47 e8 4c 0f 46 e3 49 39 ed 76 a8 e9 aa fd ff ff RSP: 0018:ffffc90000b27510 EFLAGS: 00000293 RAX: ffffffff81e45b18 RBX: ffffffff8eaf4d20 RCX: ffffffff8eaf4d24 RDX: ffffffff8f205ef4 RSI: 00000000000a0001 RDI: ffffffff813c8bc0 RBP: ffffffff8eaf4d28 R08: 0000000000000011 R09: ffffc90000b276d0 R10: ffffc90000b27630 R11: fffff52000164ec8 R12: ffffffff8eaf4d18 R13: ffffffff8eaf4d24 R14: ffffffff8eaf4d0c R15: ffffffff81e45b5e FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a25c82a600 CR3: 000000000d130000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <TASK> arch_stack_walk+0x111/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x117/0x1c0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____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:1792 [inline] slab_free_freelist_hook mm/slub.c:1818 [inline] slab_free mm/slub.c:3801 [inline] __kmem_cache_free+0x25f/0x3b0 mm/slub.c:3814 batadv_mcast_mla_list_free net/batman-adv/multicast.c:638 [inline] __batadv_mcast_mla_update net/batman-adv/multicast.c:893 [inline] batadv_mcast_mla_update+0x380a/0x3bb0 net/batman-adv/multicast.c:915 process_one_work+0x92c/0x12c0 kernel/workqueue.c:2600 worker_thread+0xa63/0x1210 kernel/workqueue.c:2751 kthread+0x2b8/0x350 kernel/kthread.c:389 ret_from_fork+0x2e/0x60 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 </TASK> --- 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 syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. 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