Hello, syzbot found the following issue on: HEAD commit: eb88e6bfbc0a Merge tag 'fsnotify_for_v6.14-rc7' of git://g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=11e6c83f980000 kernel config: https://syzkaller.appspot.com/x/.config?x=77423669c2b8fa9 dashboard link: https://syzkaller.appspot.com/bug?extid=20ed41006cf9d842c2b5 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: i386 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-eb88e6bf.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/ded0ce69669f/vmlinux-eb88e6bf.xz kernel image: https://storage.googleapis.com/syzbot-assets/6e6fa3c719e7/bzImage-eb88e6bf.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+20ed41006cf9d842c2b5@xxxxxxxxxxxxxxxxxxxxxxxxx RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> BUG: unable to handle page fault for address: fffffffffffffff4 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD df84067 P4D df84067 PUD df86067 PMD 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 1 UID: 0 PID: 17805 Comm: syz.8.3237 Not tainted 6.14.0-rc6-syzkaller-00212-geb88e6bfbc0a #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:vma_merge_existing_range+0x266/0x2070 mm/vma.c:734 Code: e8 5f 25 ad ff 48 8b 14 24 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 1c 19 00 00 48 8b 04 24 48 8b 74 24 08 <4c> 8b 38 4c 89 ff e8 9f 1f ad ff 48 8b 44 24 08 49 39 c7 0f 83 db RSP: 0000:ffffc9000319f988 EFLAGS: 00010246 RAX: fffffffffffffff4 RBX: ffffc9000319fae8 RCX: ffffffff820cd3e5 RDX: 1ffffffffffffffe RSI: 0000000080c2a000 RDI: 0000000000000005 RBP: 0000000080ce2000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000001 R13: ffffc9000319fb08 R14: ffff888025eddc98 R15: ffff88804eec0a00 FS: 0000000000000000(0000) GS:ffff88802b500000(0063) knlGS:00000000f5106b40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: fffffffffffffff4 CR3: 00000000614d6000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> vma_modify.constprop.0+0x87/0x410 mm/vma.c:1517 vma_modify_flags_uffd+0x241/0x2e0 mm/vma.c:1598 userfaultfd_clear_vma+0x91/0x130 mm/userfaultfd.c:1906 userfaultfd_release_all+0x2ae/0x4c0 mm/userfaultfd.c:2024 userfaultfd_release+0xf4/0x1c0 fs/userfaultfd.c:865 __fput+0x3ff/0xb70 fs/file_table.c:464 task_work_run+0x14e/0x250 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218 __do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:390 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:412 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7fe6579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f510655c EFLAGS: 00000296 ORIG_RAX: 0000000000000135 RAX: 0000000000000001 RBX: 0000000080000180 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> Modules linked in: CR2: fffffffffffffff4 ---[ end trace 0000000000000000 ]--- RIP: 0010:vma_merge_existing_range+0x266/0x2070 mm/vma.c:734 Code: e8 5f 25 ad ff 48 8b 14 24 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 1c 19 00 00 48 8b 04 24 48 8b 74 24 08 <4c> 8b 38 4c 89 ff e8 9f 1f ad ff 48 8b 44 24 08 49 39 c7 0f 83 db RSP: 0000:ffffc9000319f988 EFLAGS: 00010246 RAX: fffffffffffffff4 RBX: ffffc9000319fae8 RCX: ffffffff820cd3e5 RDX: 1ffffffffffffffe RSI: 0000000080c2a000 RDI: 0000000000000005 RBP: 0000000080ce2000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000001 R13: ffffc9000319fb08 R14: ffff888025eddc98 R15: ffff88804eec0a00 FS: 0000000000000000(0000) GS:ffff88802b500000(0063) knlGS:00000000f5106b40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: fffffffffffffff4 CR3: 00000000614d6000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: e8 5f 25 ad ff call 0xffad2564 5: 48 8b 14 24 mov (%rsp),%rdx 9: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 10: fc ff df 13: 48 c1 ea 03 shr $0x3,%rdx 17: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 1b: 0f 85 1c 19 00 00 jne 0x193d 21: 48 8b 04 24 mov (%rsp),%rax 25: 48 8b 74 24 08 mov 0x8(%rsp),%rsi * 2a: 4c 8b 38 mov (%rax),%r15 <-- trapping instruction 2d: 4c 89 ff mov %r15,%rdi 30: e8 9f 1f ad ff call 0xffad1fd4 35: 48 8b 44 24 08 mov 0x8(%rsp),%rax 3a: 49 39 c7 cmp %rax,%r15 3d: 0f .byte 0xf 3e: 83 .byte 0x83 3f: db .byte 0xdb --- 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
