On Sat, Oct 1, 2022 at 7:27 AM syzbot wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit: aaa11ce2ffc8 Add linux-next specific files for 20220923 > git tree: linux-next > console+strace: https://syzkaller.appspot.com/x/log.txt?x=12904574880000 > kernel config: https://syzkaller.appspot.com/x/.config?x=186d1ff305f10294 > dashboard link: https://syzkaller.appspot.com/bug?extid=76f0ebea6c1e032bbe49 > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1181a5c4880000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12bdc2e0880000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/95c7bf83c07e/disk-aaa11ce2.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/b161cd56a7a3/vmlinux-aaa11ce2.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+76f0ebea6c1e032bbe49@xxxxxxxxxxxxxxxxxxxxxxxxx > > loop0: detected capacity change from 0 to 2048 > general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN > KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] > CPU: 0 PID: 3609 Comm: syz-executor421 Not tainted 6.0.0-rc6-next-20220923-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 > RIP: 0010:nilfs_bmap_lookup_at_level+0xb5/0x3e0 fs/nilfs2/bmap.c:69 > Code: df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 95 02 00 00 48 8b 83 d8 00 00 00 48 ba 00 00 00 00 00 fc ff df 48 89 c1 48 c1 e9 03 <80> 3c 11 00 0f 85 7d 02 00 00 4c 89 e6 48 89 e9 44 89 fa 48 89 df > RSP: 0018:ffffc90003caf6d8 EFLAGS: 00010246 > RAX: 0000000000000000 RBX: ffff8880738da688 RCX: 0000000000000000 > RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff8880738da760 > RBP: ffffc90003caf7b8 R08: 0000000000000001 R09: ffff8880738da6cf > R10: ffffed100e71b4d9 R11: 000000000008c07e R12: 0000000000000002 > R13: 1ffff92000795edc R14: ffff8880738da6c0 R15: 0000000000000001 > FS: 0000555555ac8300(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00000000005d84c8 CR3: 000000005942f000 CR4: 00000000003506f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > <TASK> > nilfs_bmap_lookup fs/nilfs2/bmap.h:170 [inline] > nilfs_mdt_submit_block+0x1a1/0xb40 fs/nilfs2/mdt.c:142 > nilfs_mdt_read_block+0x92/0x3c0 fs/nilfs2/mdt.c:176 > nilfs_mdt_get_block+0xe3/0xe00 fs/nilfs2/mdt.c:251 > nilfs_palloc_get_block+0xc4/0x2b0 fs/nilfs2/alloc.c:216 > nilfs_palloc_get_entry_block+0x167/0x1d0 fs/nilfs2/alloc.c:318 > nilfs_ifile_get_inode_block+0xbf/0x190 fs/nilfs2/ifile.c:143 > __nilfs_read_inode fs/nilfs2/inode.c:477 [inline] > nilfs_iget+0x208/0x870 fs/nilfs2/inode.c:603 > nilfs_get_root_dentry+0x26/0x240 fs/nilfs2/super.c:904 > nilfs_fill_super fs/nilfs2/super.c:1078 [inline] > nilfs_mount+0xbb2/0xfb0 fs/nilfs2/super.c:1317 > legacy_get_tree+0x105/0x220 fs/fs_context.c:610 > vfs_get_tree+0x89/0x2f0 fs/super.c:1530 > do_new_mount fs/namespace.c:3040 [inline] > path_mount+0x1326/0x1e20 fs/namespace.c:3370 > do_mount fs/namespace.c:3383 [inline] > __do_sys_mount fs/namespace.c:3591 [inline] > __se_sys_mount fs/namespace.c:3568 [inline] > __x64_sys_mount+0x27f/0x300 fs/namespace.c:3568 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x63/0xcd > RIP: 0033:0x7fd84078b60a > Code: 83 c4 08 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 > RSP: 002b:00007ffc2a043bd8 EFLAGS: 00000286 ORIG_RAX: 00000000000000a5 > RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fd84078b60a > RDX: 0000000020000000 RSI: 0000000020000080 RDI: 00007ffc2a043bf0 > RBP: 00007ffc2a043bf0 R08: 00007ffc2a043c30 R09: 0000555555ac82c0 > R10: 0000000000000000 R11: 0000000000000286 R12: 0000000000000004 > R13: 00007ffc2a043c30 R14: 000000000000003a R15: 0000000020000770 > </TASK> > Modules linked in: > ---[ end trace 0000000000000000 ]--- > RIP: 0010:nilfs_bmap_lookup_at_level+0xb5/0x3e0 fs/nilfs2/bmap.c:69 > Code: df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 95 02 00 00 48 8b 83 d8 00 00 00 48 ba 00 00 00 00 00 fc ff df 48 89 c1 48 c1 e9 03 <80> 3c 11 00 0f 85 7d 02 00 00 4c 89 e6 48 89 e9 44 89 fa 48 89 df > RSP: 0018:ffffc90003caf6d8 EFLAGS: 00010246 > RAX: 0000000000000000 RBX: ffff8880738da688 RCX: 0000000000000000 > RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff8880738da760 > RBP: ffffc90003caf7b8 R08: 0000000000000001 R09: ffff8880738da6cf > R10: ffffed100e71b4d9 R11: 000000000008c07e R12: 0000000000000002 > R13: 1ffff92000795edc R14: ffff8880738da6c0 R15: 0000000000000001 > FS: 0000555555ac8300(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00000000005d84c8 CR3: 000000005942f000 CR4: 00000000003506f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > ---------------- > Code disassembly (best guess): > 0: df 48 89 fisttps -0x77(%rax) > 3: fa cli > 4: 48 c1 ea 03 shr $0x3,%rdx > 8: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) > c: 0f 85 95 02 00 00 jne 0x2a7 > 12: 48 8b 83 d8 00 00 00 mov 0xd8(%rbx),%rax > 19: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx > 20: fc ff df > 23: 48 89 c1 mov %rax,%rcx > 26: 48 c1 e9 03 shr $0x3,%rcx > * 2a: 80 3c 11 00 cmpb $0x0,(%rcx,%rdx,1) <-- trapping instruction > 2e: 0f 85 7d 02 00 00 jne 0x2b1 > 34: 4c 89 e6 mov %r12,%rsi > 37: 48 89 e9 mov %rbp,%rcx > 3a: 44 89 fa mov %r15d,%edx > 3d: 48 89 df mov %rbx,%rdi > > > --- > 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. > syzbot can test patches for this issue, for details see: > https://goo.gl/tpsmEJ#testing-patches #syz dup: INFO: trying to register non-static key in nilfs_bmap_lookup_at_level I confirmed that the patch titled "nilfs2: fix NULL pointer dereference at nilfs_bmap_lookup_at_level()" which I submitted for the above issue also fixes this oops. Ryusuke Konishi
