Hello, syzbot found the following issue on: HEAD commit: d93a0d43 Merge tag 'block-5.12-2021-04-02' of git://git.ke.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16519431d00000 kernel config: https://syzkaller.appspot.com/x/.config?x=71a75beb62b62a34 dashboard link: https://syzkaller.appspot.com/bug?extid=11c49ce9d4e7896f3406 compiler: Debian clang version 11.0.1-2 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+11c49ce9d4e7896f3406@xxxxxxxxxxxxxxxxxxxxxxxxx REISERFS (device loop4): Using r5 hash to sort names BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 6bb82067 P4D 6bb82067 PUD 6bb81067 PMD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 0 PID: 11072 Comm: syz-executor.4 Not tainted 5.12.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:0x0 Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. RSP: 0018:ffffc90008f8fa20 EFLAGS: 00010246 RAX: 1ffffffff13872e8 RBX: dffffc0000000000 RCX: 0000000000040000 RDX: 0000000000000000 RSI: ffff88802e9d9490 RDI: ffff88807f140190 RBP: ffffffff89c39740 R08: ffffffff81c9d4de R09: fffffbfff200a946 R10: fffffbfff200a946 R11: 0000000000000000 R12: 0000000000000000 R13: ffff88807f140190 R14: 1ffff11005d3b292 R15: ffff88802e9d9490 FS: 00007f894af88700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000006bb83000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lookup_slow+0x240/0x370 fs/namei.c:1626 lookup_one_len+0x10e/0x200 fs/namei.c:2649 reiserfs_lookup_privroot+0x85/0x1e0 fs/reiserfs/xattr.c:980 reiserfs_fill_super+0x2a69/0x3160 fs/reiserfs/super.c:2176 mount_bdev+0x26c/0x3a0 fs/super.c:1367 legacy_get_tree+0xea/0x180 fs/fs_context.c:592 vfs_get_tree+0x86/0x270 fs/super.c:1497 do_new_mount fs/namespace.c:2903 [inline] path_mount+0x188a/0x29a0 fs/namespace.c:3233 do_mount fs/namespace.c:3246 [inline] __do_sys_mount fs/namespace.c:3454 [inline] __se_sys_mount+0x28c/0x320 fs/namespace.c:3431 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x46797a Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f894af87fa8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 000000000046797a RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f894af88000 RBP: 00007f894af88040 R08: 00007f894af88040 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000 R13: 0000000020000100 R14: 00007f894af88000 R15: 0000000020011500 Modules linked in: CR2: 0000000000000000 ---[ end trace a1b8dbb111baf993 ]--- RIP: 0010:0x0 Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. RSP: 0018:ffffc90008f8fa20 EFLAGS: 00010246 RAX: 1ffffffff13872e8 RBX: dffffc0000000000 RCX: 0000000000040000 RDX: 0000000000000000 RSI: ffff88802e9d9490 RDI: ffff88807f140190 RBP: ffffffff89c39740 R08: ffffffff81c9d4de R09: fffffbfff200a946 R10: fffffbfff200a946 R11: 0000000000000000 R12: 0000000000000000 R13: ffff88807f140190 R14: 1ffff11005d3b292 R15: ffff88802e9d9490 FS: 00007f894af88700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 000000006bb83000 CR4: 00000000001506f0 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 syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
