Hello, syzbot found the following issue on: HEAD commit: 4af7b32f Merge git://git.kernel.org/pub/scm/linux/kernel/g.. git tree: bpf console output: https://syzkaller.appspot.com/x/log.txt?x=1425b649900000 kernel config: https://syzkaller.appspot.com/x/.config?x=3d400a47d1416652 dashboard link: https://syzkaller.appspot.com/bug?extid=9e6957d9489b099e95bf compiler: gcc (GCC) 10.1.0-syz 20200507 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+9e6957d9489b099e95bf@xxxxxxxxxxxxxxxxxxxxxxxxx ------------[ cut here ]------------ kernel BUG at fs/ext4/page-io.c:126! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 25034 Comm: syz-executor.2 Not tainted 5.9.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:ext4_finish_bio+0x6a0/0x820 fs/ext4/page-io.c:126 Code: 10 4c 8b 60 28 48 89 44 24 50 e9 2b fb ff ff e8 c6 65 68 ff 48 c7 c6 60 b8 5d 88 4c 89 e7 e8 a7 c8 96 ff 0f 0b e8 b0 65 68 ff <0f> 0b e8 a9 65 68 ff 48 c7 c6 60 b7 5d 88 4c 89 e7 e8 8a c8 96 ff RSP: 0018:ffffc90000da8b28 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000001000 RCX: ffffffff820bd8f6 RDX: ffff88809a8e4380 RSI: ffffffff820bdbd0 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000000 R09: ffff8880857a8ddf R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880857a8dd8 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000 FS: 00007fb6570cf700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcfa3e6800 CR3: 00000000a3c6b000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> ext4_end_bio+0x179/0x5e0 fs/ext4/page-io.c:368 bio_endio+0x3cf/0x7f0 block/bio.c:1447 req_bio_endio block/blk-core.c:259 [inline] blk_update_request+0x68c/0x1230 block/blk-core.c:1576 scsi_end_request+0x7e/0x8f0 drivers/scsi/scsi_lib.c:566 scsi_io_completion+0x1df/0x1310 drivers/scsi/scsi_lib.c:938 scsi_softirq_done+0x327/0x3c0 drivers/scsi/scsi_lib.c:1464 blk_done_softirq+0x2db/0x430 block/blk-mq.c:586 __do_softirq+0x2de/0xa24 kernel/softirq.c:298 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 </IRQ> __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0x9d/0xd0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0x1f3/0x230 kernel/softirq.c:435 common_interrupt+0xa3/0x1f0 arch/x86/kernel/irq.c:239 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:572 RIP: 0010:partial_name_hash include/linux/stringhash.h:45 [inline] RIP: 0010:kernfs_name_hash+0x93/0x120 fs/kernfs/dir.c:304 Code: 48 c1 e8 03 83 e2 07 42 0f b6 04 20 38 d0 7f 08 84 c0 0f 85 8f 00 00 00 49 0f be 77 ff 31 ff 48 89 f0 48 c1 ee 04 48 c1 e0 04 <48> 01 c6 4c 01 f6 48 8d 04 b6 4c 8d 34 46 89 ee e8 98 97 8b ff 49 RSP: 0018:ffffc9000659f950 EFLAGS: 00000202 RAX: 0000000000000620 RBX: ffffffff89007753 RCX: ffffc9000ce73000 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000000 RBP: 000000000000000a R08: 000000000000000a R09: ffff88808acdfbcf R10: 0000000000000000 R11: 0000000000000001 R12: dffffc0000000000 R13: 000000008900773f R14: 000000666c06666f R15: ffffffff89007749 kernfs_add_one+0x1e6/0x4c0 fs/kernfs/dir.c:785 __kernfs_create_file+0x299/0x350 fs/kernfs/file.c:1031 sysfs_add_file_mode_ns+0x226/0x540 fs/sysfs/file.c:305 create_files fs/sysfs/group.c:64 [inline] internal_create_group+0x328/0xb20 fs/sysfs/group.c:149 internal_create_groups.part.0+0x90/0x140 fs/sysfs/group.c:189 internal_create_groups fs/sysfs/group.c:185 [inline] sysfs_create_groups+0x25/0x50 fs/sysfs/group.c:215 device_add_groups drivers/base/core.c:2024 [inline] device_add_attrs drivers/base/core.c:2183 [inline] device_add+0x12fc/0x1c40 drivers/base/core.c:2881 netdev_register_kobject+0x17d/0x3b0 net/core/net-sysfs.c:1898 register_netdevice+0xd29/0x1540 net/core/dev.c:9829 __tun_chr_ioctl.isra.0+0x2c09/0x41b0 drivers/net/tun.c:2804 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d4d9 Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fb6570cec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000019e00 RCX: 000000000045d4d9 RDX: 00000000200000c0 RSI: 00000000400454ca RDI: 0000000000000006 RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 00007ffdc2238a7f R14: 00007fb6570cf9c0 R15: 000000000118cf4c Modules linked in: ---[ end trace 59bc8db21b5f0a1a ]--- RIP: 0010:ext4_finish_bio+0x6a0/0x820 fs/ext4/page-io.c:126 Code: 10 4c 8b 60 28 48 89 44 24 50 e9 2b fb ff ff e8 c6 65 68 ff 48 c7 c6 60 b8 5d 88 4c 89 e7 e8 a7 c8 96 ff 0f 0b e8 b0 65 68 ff <0f> 0b e8 a9 65 68 ff 48 c7 c6 60 b7 5d 88 4c 89 e7 e8 8a c8 96 ff RSP: 0018:ffffc90000da8b28 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000001000 RCX: ffffffff820bd8f6 RDX: ffff88809a8e4380 RSI: ffffffff820bdbd0 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000000 R09: ffff8880857a8ddf R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880857a8dd8 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000 FS: 00007fb6570cf700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcfa3e6800 CR3: 00000000a3c6b000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 --- This report is generated by a bot. 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