Hello, syzbot found the following issue on: HEAD commit: 626932085009 Add linux-next specific files for 20230825 git tree: linux-next console+strace: https://syzkaller.appspot.com/x/log.txt?x=129f740ba80000 kernel config: https://syzkaller.appspot.com/x/.config?x=8a8c992a790e5073 dashboard link: https://syzkaller.appspot.com/bug?extid=dd327730db1381d8d2a2 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15cbe42fa80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17eab870680000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/46ec18b3c2fb/disk-62693208.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/b4ea0cb78498/vmlinux-62693208.xz kernel image: https://storage.googleapis.com/syzbot-assets/5fb3938c7272/bzImage-62693208.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/f4d93eaec6e2/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+dd327730db1381d8d2a2@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task kworker/u4:13:2908 blocked for more than 143 seconds. Not tainted 6.5.0-rc7-next-20230825-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:13 state:D stack:25664 pid:2908 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: <TASK> context_switch kernel/sched/core.c:5382 [inline] __schedule+0xee1/0x59f0 kernel/sched/core.c:6695 schedule+0xe7/0x1b0 kernel/sched/core.c:6771 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6830 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x967/0x1340 kernel/locking/mutex.c:747 hfs_find_init+0x17f/0x220 fs/hfs/bfind.c:33 hfs_ext_write_extent+0x18e/0x1f0 fs/hfs/extent.c:141 hfs_write_inode+0xc4/0x9f0 fs/hfs/inode.c:431 write_inode fs/fs-writeback.c:1456 [inline] __writeback_single_inode+0xa81/0xe70 fs/fs-writeback.c:1668 writeback_sb_inodes+0x599/0x1010 fs/fs-writeback.c:1894 __writeback_inodes_wb+0xff/0x2d0 fs/fs-writeback.c:1965 wb_writeback+0x7f8/0xa90 fs/fs-writeback.c:2072 wb_check_background_flush fs/fs-writeback.c:2142 [inline] wb_do_writeback fs/fs-writeback.c:2230 [inline] wb_workfn+0x874/0xfd0 fs/fs-writeback.c:2257 process_one_work+0x887/0x15d0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8bb/0x1290 kernel/workqueue.c:2784 kthread+0x33a/0x430 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 </TASK> INFO: task syz-executor624:5050 blocked for more than 143 seconds. Not tainted 6.5.0-rc7-next-20230825-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor624 state:D stack:26944 pid:5050 ppid:5049 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5382 [inline] __schedule+0xee1/0x59f0 kernel/sched/core.c:6695 schedule+0xe7/0x1b0 kernel/sched/core.c:6771 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6830 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x967/0x1340 kernel/locking/mutex.c:747 hfs_find_init+0x17f/0x220 fs/hfs/bfind.c:33 hfs_ext_read_extent+0x19c/0x9d0 fs/hfs/extent.c:200 hfs_extend_file+0x4e0/0xb10 fs/hfs/extent.c:401 hfs_bmap_reserve+0x29c/0x370 fs/hfs/btree.c:234 __hfs_ext_write_extent+0x3cb/0x520 fs/hfs/extent.c:121 __hfs_ext_cache_extent fs/hfs/extent.c:174 [inline] hfs_ext_read_extent+0x805/0x9d0 fs/hfs/extent.c:202 hfs_extend_file+0x4e0/0xb10 fs/hfs/extent.c:401 hfs_get_block+0x17f/0x820 fs/hfs/extent.c:353 __block_write_begin_int+0x3c0/0x1470 fs/buffer.c:2107 __block_write_begin fs/buffer.c:2157 [inline] block_write_begin+0xb1/0x490 fs/buffer.c:2216 cont_write_begin+0x52f/0x730 fs/buffer.c:2573 hfs_write_begin+0x87/0x140 fs/hfs/inode.c:58 generic_perform_write+0x278/0x600 mm/filemap.c:3945 __generic_file_write_iter+0x1f9/0x240 mm/filemap.c:4040 generic_file_write_iter+0xe3/0x350 mm/filemap.c:4066 call_write_iter include/linux/fs.h:1985 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x650/0xe40 fs/read_write.c:584 ksys_write+0x12f/0x250 fs/read_write.c:637 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 RIP: 0033:0x7f7094b1ea59 RSP: 002b:00007ffe889a4368 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7094b1ea59 RDX: 000000000208e24b RSI: 0000000020000180 RDI: 0000000000000004 RBP: 00007f7094b925f0 R08: 00005555570c84c0 R09: 00005555570c84c0 R10: 00000000000002ba R11: 0000000000000246 R12: 00007ffe889a4390 R13: 00007ffe889a45b8 R14: 431bde82d7b634db R15: 00007f7094b6703b </TASK> INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.5.0-rc7-next-20230825-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+0xd9/0x1b0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x299/0x300 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+0xfac/0x1230 kernel/hung_task.c:379 kthread+0x33a/0x430 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 </TASK> Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4486 Comm: klogd Not tainted 6.5.0-rc7-next-20230825-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x8/0x20 kernel/kcov.c:290 Code: 00 00 f3 0f 1e fa 48 8b 0c 24 48 89 f2 48 89 fe bf 06 00 00 00 e9 f8 fe ff ff 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 48 8b 0c 24 <40> 0f b6 d6 40 0f b6 f7 bf 01 00 00 00 e9 d6 fe ff ff 66 0f 1f 44 RSP: 0018:ffffc9000316f4a0 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffffc9000316f528 RCX: ffffffff813a6214 RDX: ffff88807d690000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffc9000316fca8 R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000001 FS: 00007faa97852380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056143bacf680 CR3: 000000007d4dd000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <TASK> deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] unwind_next_frame+0x1aa4/0x2390 arch/x86/kernel/unwind_orc.c:648 arch_stack_walk+0xfa/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x96/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:328 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+0x185/0x3f0 mm/slub.c:3523 __alloc_skb+0x287/0x330 net/core/skbuff.c:634 alloc_skb include/linux/skbuff.h:1286 [inline] alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6299 sock_alloc_send_pskb+0x7c8/0x950 net/core/sock.c:2794 unix_dgram_sendmsg+0x455/0x1c30 net/unix/af_unix.c:1953 sock_sendmsg_nosec net/socket.c:730 [inline] sock_sendmsg+0xd9/0x180 net/socket.c:753 __sys_sendto+0x255/0x340 net/socket.c:2176 __do_sys_sendto net/socket.c:2188 [inline] __se_sys_sendto net/socket.c:2184 [inline] __x64_sys_sendto+0xe0/0x1b0 net/socket.c:2184 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 RIP: 0033:0x7faa979b49b5 Code: 8b 44 24 08 48 83 c4 28 48 98 c3 48 98 c3 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 26 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 7a 48 8b 15 44 c4 0c 00 f7 d8 64 89 02 48 83 RSP: 002b:00007fffe91a6858 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007faa979b49b5 RDX: 000000000000008b RSI: 000055f315610e90 RDI: 0000000000000003 RBP: 000055f31560c910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000013 R13: 00007faa97b42212 R14: 00007fffe91a6958 R15: 0000000000000000 </TASK> INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.859 msecs --- 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
