Hello, syzbot found the following issue on: HEAD commit: 2dac75696c6d Add linux-next specific files for 20231018 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=13858275680000 kernel config: https://syzkaller.appspot.com/x/.config?x=6f8545e1ef7a2b66 dashboard link: https://syzkaller.appspot.com/bug?extid=1e2648076cadf48ad9a1 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=17543ee5680000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=101f5fe5680000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/2375f16ed327/disk-2dac7569.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/c80aee6e2e6c/vmlinux-2dac7569.xz kernel image: https://storage.googleapis.com/syzbot-assets/664dc23b738d/bzImage-2dac7569.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+1e2648076cadf48ad9a1@xxxxxxxxxxxxxxxxxxxxxxxxx general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 5710 Comm: syz-executor155 Not tainted 6.6.0-rc6-next-20231018-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 RIP: 0010:PageTail include/linux/page-flags.h:286 [inline] RIP: 0010:folio_flags.constprop.0+0x21/0x150 include/linux/page-flags.h:313 Code: 84 00 00 00 00 00 0f 1f 00 41 54 55 53 48 89 fb e8 14 2f a4 ff 48 8d 7b 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 00 01 00 00 48 8b 6b 08 31 ff 83 e5 01 48 89 ee RSP: 0018:ffffc90004367968 EFLAGS: 00010247 RAX: dffffc0000000000 RBX: fffffffffffffffe RCX: ffffffff81b7e126 RDX: 0000000000000000 RSI: ffffffff81e49d1c RDI: 0000000000000006 RBP: 0000000020200000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 1ffffffff1976fb9 R12: ffff88801675b900 R13: ffff888025f9f680 R14: fffffffffffffffe R15: 1ffff9200086cf3d FS: 00007f2f2a17c6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2f2a17cd58 CR3: 000000001bfa0000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> folio_test_head include/linux/page-flags.h:790 [inline] folio_test_large include/linux/page-flags.h:811 [inline] folio_order include/linux/mm.h:1079 [inline] collapse_pte_mapped_thp+0x42d/0x13b0 mm/khugepaged.c:1512 madvise_collapse+0x875/0xaf0 mm/khugepaged.c:2761 madvise_vma_behavior+0x1fe/0x1d00 mm/madvise.c:1086 madvise_walk_vmas+0x1cf/0x2c0 mm/madvise.c:1260 do_madvise+0x333/0x660 mm/madvise.c:1440 __do_sys_madvise mm/madvise.c:1453 [inline] __se_sys_madvise mm/madvise.c:1451 [inline] __x64_sys_madvise+0xaa/0x110 mm/madvise.c:1451 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f2f2a1dc7a9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 01 1a 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2f2a17c238 EFLAGS: 00000246 ORIG_RAX: 000000000000001c RAX: ffffffffffffffda RBX: 00007f2f2a266318 RCX: 00007f2f2a1dc7a9 RDX: 0000000000000019 RSI: 000000000060005f RDI: 0000000020000000 RBP: 00007f2f2a266310 R08: 00007ffe616d77f7 R09: 00007f2f2a17c6c0 R10: 0000000000000000 R11: 0000000000000246 R12: b635773f07ebbeef R13: 000000000000006e R14: 00007ffe616d7710 R15: 00007ffe616d77f8 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:PageTail include/linux/page-flags.h:286 [inline] RIP: 0010:folio_flags.constprop.0+0x21/0x150 include/linux/page-flags.h:313 Code: 84 00 00 00 00 00 0f 1f 00 41 54 55 53 48 89 fb e8 14 2f a4 ff 48 8d 7b 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 00 01 00 00 48 8b 6b 08 31 ff 83 e5 01 48 89 ee RSP: 0018:ffffc90004367968 EFLAGS: 00010247 RAX: dffffc0000000000 RBX: fffffffffffffffe RCX: ffffffff81b7e126 RDX: 0000000000000000 RSI: ffffffff81e49d1c RDI: 0000000000000006 RBP: 0000000020200000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 1ffffffff1976fb9 R12: ffff88801675b900 R13: ffff888025f9f680 R14: fffffffffffffffe R15: 1ffff9200086cf3d FS: 00007f2f2a17c6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2f2a17cd58 CR3: 000000001bfa0000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 84 00 test %al,(%rax) 2: 00 00 add %al,(%rax) 4: 00 00 add %al,(%rax) 6: 0f 1f 00 nopl (%rax) 9: 41 54 push %r12 b: 55 push %rbp c: 53 push %rbx d: 48 89 fb mov %rdi,%rbx 10: e8 14 2f a4 ff call 0xffa42f29 15: 48 8d 7b 08 lea 0x8(%rbx),%rdi 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 20: fc ff df 23: 48 89 fa mov %rdi,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 0f 85 00 01 00 00 jne 0x134 34: 48 8b 6b 08 mov 0x8(%rbx),%rbp 38: 31 ff xor %edi,%edi 3a: 83 e5 01 and $0x1,%ebp 3d: 48 89 ee mov %rbp,%rsi --- 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
