On Thursday, October 31st, 2024 at 10:09 PM, Piotr Zalewski <[email protected]> wrote:
> It reads garbage error options from superblock. Proper way to handle this > seems to be checking if read option value is valid (within range, error > options are represented on 4 bits but <= 3 values are used) and if it's not > - set/leave the default. Found that options are already validated in bch2_sb_validate but max is wrong for option type OPT_STR. Will send a patch. > > On Sunday, October 27th, 2024 at 4:54 AM, syzbot > [email protected] wrote: > > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit: c2ee9f594da8 KVM: selftests: Fix build on on non-x86 archi.. > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=14202a5f980000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=fc6f8ce8c5369043 > > dashboard link: https://syzkaller.appspot.com/bug?extid=bee87a0c3291c06aa8c6 > > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11468c30580000 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=166fa640580000 > > > > Downloadable assets: > > disk image (non-bootable): > > https://storage.googleapis.com/syzbot-assets/7feb34a89c2a/non_bootable_disk-c2ee9f59.raw.xz > > vmlinux: > > https://storage.googleapis.com/syzbot-assets/8a3541902b13/vmlinux-c2ee9f59.xz > > kernel image: > > https://storage.googleapis.com/syzbot-assets/a00efacc2604/bzImage-c2ee9f59.xz > > mounted in repro: > > https://storage.googleapis.com/syzbot-assets/7da30fa86689/mount_0.gz > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > Reported-by: [email protected] > > > > ------------[ cut here ]------------ > > kernel BUG at fs/bcachefs/error.c:29! > > Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI > > CPU: 0 UID: 0 PID: 5094 Comm: syz-executor353 Not tainted > > 6.12.0-rc4-syzkaller-00047-gc2ee9f594da8 #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:bch2_inconsistent_error+0x14c/0x150 fs/bcachefs/error.c:29 > > Code: fb 02 75 20 e8 f5 53 67 fd 49 81 c7 cc 01 00 00 e8 09 0c d1 fd 48 c7 > > c7 20 74 53 8c 4c 89 fe e8 2a cb 95 07 e8 d5 53 67 fd 90 <0f> 0b 66 90 90 > > 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f > > > > RSP: 0018:ffffc9000b0965f8 EFLAGS: 00010293 > > RAX: ffffffff842d840b RBX: 0000000000000004 RCX: ffff8880359c8000 > > RDX: 0000000000000000 RSI: ffffffff8ef57290 RDI: 0000000000000004 > > RBP: ffffc9000b0967a8 R08: 0000000000000001 R09: ffffffff842d8324 > > R10: 0000000000000004 R11: ffff8880359c8000 R12: dffffc0000000000 > > R13: ffffc9000b0966c0 R14: ffff888044c00000 R15: ffff888044c00000 > > FS: 00005555742e5380(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000 > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > CR2: 00007ffe064e9e68 CR3: 000000003df88000 CR4: 0000000000352ef0 > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > Call Trace: > > <TASK> > > > > bch2_topology_error+0x83/0xc0 fs/bcachefs/error.c:37 > > __btree_err+0x610/0x760 fs/bcachefs/btree_io.c:597 > > validate_bset+0x157b/0x2640 fs/bcachefs/btree_io.c:807 > > bch2_btree_node_read_done+0x2108/0x5e90 fs/bcachefs/btree_io.c:1126 > > btree_node_read_work+0x68b/0x1260 fs/bcachefs/btree_io.c:1327 > > bch2_btree_node_read+0x2433/0x2a10 > > __bch2_btree_root_read fs/bcachefs/btree_io.c:1753 [inline] > > bch2_btree_root_read+0x617/0x7a0 fs/bcachefs/btree_io.c:1775 > > read_btree_roots+0x296/0x840 fs/bcachefs/recovery.c:524 > > bch2_fs_recovery+0x2585/0x39c0 fs/bcachefs/recovery.c:854 > > bch2_fs_start+0x356/0x5b0 fs/bcachefs/super.c:1036 > > bch2_fs_get_tree+0xd68/0x1710 fs/bcachefs/fs.c:2174 > > vfs_get_tree+0x90/0x2b0 fs/super.c:1800 > > do_new_mount+0x2be/0xb40 fs/namespace.c:3507 > > do_mount fs/namespace.c:3847 [inline] > > __do_sys_mount fs/namespace.c:4057 [inline] > > __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034 > > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > > do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 > > entry_SYSCALL_64_after_hwframe+0x77/0x7f > > RIP: 0033:0x7f1aa39038fa > > Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 5e 04 00 00 66 2e 0f 1f 84 > > 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff > > ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 > > > > RSP: 002b:00007ffddefb1b08 EFLAGS: 00000282 ORIG_RAX: 00000000000000a5 > > RAX: ffffffffffffffda RBX: 00007ffddefb1b20 RCX: 00007f1aa39038fa > > RDX: 0000000020000300 RSI: 0000000020005900 RDI: 00007ffddefb1b20 > > RBP: 0000000000000004 R08: 00007ffddefb1b60 R09: 00000000000058c4 > > R10: 0000000000000000 R11: 0000000000000282 R12: 0000000000000000 > > R13: 00007ffddefb1b60 R14: 0000000000000003 R15: 0000000001000000 > > </TASK> > > > > Modules linked in: > > ---[ end trace 0000000000000000 ]--- > > RIP: 0010:bch2_inconsistent_error+0x14c/0x150 fs/bcachefs/error.c:29 > > Code: fb 02 75 20 e8 f5 53 67 fd 49 81 c7 cc 01 00 00 e8 09 0c d1 fd 48 c7 > > c7 20 74 53 8c 4c 89 fe e8 2a cb 95 07 e8 d5 53 67 fd 90 <0f> 0b 66 90 90 > > 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f > > > > RSP: 0018:ffffc9000b0965f8 EFLAGS: 00010293 > > RAX: ffffffff842d840b RBX: 0000000000000004 RCX: ffff8880359c8000 > > RDX: 0000000000000000 RSI: ffffffff8ef57290 RDI: 0000000000000004 > > RBP: ffffc9000b0967a8 R08: 0000000000000001 R09: ffffffff842d8324 > > R10: 0000000000000004 R11: ffff8880359c8000 R12: dffffc0000000000 > > R13: ffffc9000b0966c0 R14: ffff888044c00000 R15: ffff888044c00000 > > FS: 00005555742e5380(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000 > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > CR2: 00007ffe064e9e68 CR3: 000000003df88000 CR4: 0000000000352ef0 > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > > > --- > > 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 [email protected]. > > > > 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 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 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
