Hello, syzbot found the following issue on: HEAD commit: e32cde8d2bd7 Merge tag 'sched_ext-for-6.12-rc1-fixes-1' of.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=136ae580580000 kernel config: https://syzkaller.appspot.com/x/.config?x=1b5201b91035a876 dashboard link: https://syzkaller.appspot.com/bug?extid=af5c06208fa71bf31b16 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 (non-bootable): https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-e32cde8d.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/b8759dd370e1/vmlinux-e32cde8d.xz kernel image: https://storage.googleapis.com/syzbot-assets/c770fb4b8507/bzImage-e32cde8d.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+af5c06208fa71bf31b16@xxxxxxxxxxxxxxxxxxxxxxxxx Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 0 UID: 0 PID: 1109 Comm: kworker/u32:8 Not tainted 6.12.0-rc1-syzkaller-00031-ge32cde8d2bd7 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: events_unbound netfs_write_collection_worker RIP: 0010:folioq_folio include/linux/folio_queue.h:277 [inline] RIP: 0010:netfs_writeback_unlock_folios fs/netfs/write_collect.c:107 [inline] RIP: 0010:netfs_collect_write_results fs/netfs/write_collect.c:493 [inline] RIP: 0010:netfs_write_collection_worker+0x1c97/0x4780 fs/netfs/write_collect.c:551 Code: 4c 39 fb 0f 83 25 04 00 00 e8 e5 94 54 ff 44 8b 2c 24 41 83 fd 1e 0f 87 77 23 00 00 4a 8d 44 ed 08 48 89 44 24 30 48 c1 e8 03 <42> 80 3c 30 00 0f 85 4f 23 00 00 4a 8b 5c ed 08 48 89 df e8 d1 da RSP: 0018:ffffc90005d6fae8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8238f165 RDX: ffff888026c4a440 RSI: ffffffff8238f40b RDI: 0000000000000005 RBP: 0000000000000000 R08: ffff88805f4fc600 R09: 000000000000001e R10: 0000000000000000 R11: 0000000000000000 R12: 000000000000002c R13: 0000000000000000 R14: dffffc0000000000 R15: ffff88805f4fc5fa FS: 0000000000000000(0000) GS:ffff88806a600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055960e035c38 CR3: 0000000056af8000 CR4: 0000000000352ef0 Call Trace: <TASK> process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:folioq_folio include/linux/folio_queue.h:277 [inline] RIP: 0010:netfs_writeback_unlock_folios fs/netfs/write_collect.c:107 [inline] RIP: 0010:netfs_collect_write_results fs/netfs/write_collect.c:493 [inline] RIP: 0010:netfs_write_collection_worker+0x1c97/0x4780 fs/netfs/write_collect.c:551 Code: 4c 39 fb 0f 83 25 04 00 00 e8 e5 94 54 ff 44 8b 2c 24 41 83 fd 1e 0f 87 77 23 00 00 4a 8d 44 ed 08 48 89 44 24 30 48 c1 e8 03 <42> 80 3c 30 00 0f 85 4f 23 00 00 4a 8b 5c ed 08 48 89 df e8 d1 da RSP: 0018:ffffc90005d6fae8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8238f165 RDX: ffff888026c4a440 RSI: ffffffff8238f40b RDI: 0000000000000005 RBP: 0000000000000000 R08: ffff88805f4fc600 R09: 000000000000001e R10: 0000000000000000 R11: 0000000000000000 R12: 000000000000002c R13: 0000000000000000 R14: dffffc0000000000 R15: ffff88805f4fc5fa FS: 0000000000000000(0000) GS:ffff88806a800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f989f7fd870 CR3: 000000000df7c000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 4c 39 fb cmp %r15,%rbx 3: 0f 83 25 04 00 00 jae 0x42e 9: e8 e5 94 54 ff call 0xff5494f3 e: 44 8b 2c 24 mov (%rsp),%r13d 12: 41 83 fd 1e cmp $0x1e,%r13d 16: 0f 87 77 23 00 00 ja 0x2393 1c: 4a 8d 44 ed 08 lea 0x8(%rbp,%r13,8),%rax 21: 48 89 44 24 30 mov %rax,0x30(%rsp) 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 30 00 cmpb $0x0,(%rax,%r14,1) <-- trapping instruction 2f: 0f 85 4f 23 00 00 jne 0x2384 35: 4a 8b 5c ed 08 mov 0x8(%rbp,%r13,8),%rbx 3a: 48 89 df mov %rbx,%rdi 3d: e8 .byte 0xe8 3e: d1 da rcr %edx --- 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 report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
