syzbot


general protection fault in dax_alloc_inode

Status: fixed on 2017/12/04 08:08
Subsystems: cxl nvdimm
[Documentation on labels]
Reported-by: syzbot+d681aa1d5b9189045b7015bd620e77f8406b76d2@syzkaller.appspotmail.com
Fix commit: 9f586fff6574 dax: fix general protection fault in dax_alloc_inode
First crash: 2376d, last: 2376d

Sample crash report:
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 31095 Comm: syz-executor3 Not tainted 4.14.0-rc8+ #75
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801cae96000 task.stack: ffff8801d2438000
RIP: 0010:dax_alloc_inode+0x3b/0x70 drivers/dax/super.c:348
RSP: 0018:ffff8801d243f8d0 EFLAGS: 00010203
RAX: 0000000000000010 RBX: 0000000000000000 RCX: 000000000000000b
RDX: dffffc0000000000 RSI: ffffffff85b34340 RDI: 000000000000005c
RBP: ffff8801d243f8e0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff83595ba0
R13: dffffc0000000000 R14: ffff8801cedbc5c0 R15: 0000000064646178
FS:  0000000000000000(0000) GS:ffff8801db300000(0063) knlGS:00000000f7742b40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f778cdb0 CR3: 00000001c5739000 CR4: 00000000001406e0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 alloc_inode+0x65/0x180 fs/inode.c:208
 new_inode_pseudo+0x69/0x190 fs/inode.c:890
 new_inode+0x1c/0x40 fs/inode.c:919
 mount_pseudo_xattr+0x288/0x560 fs/libfs.c:261
 mount_pseudo include/linux/fs.h:2137 [inline]
 dax_mount+0x2e/0x40 drivers/dax/super.c:388
 mount_fs+0x66/0x2d0 fs/super.c:1223
 vfs_kern_mount.part.26+0xc6/0x4a0 fs/namespace.c:1037
 vfs_kern_mount fs/namespace.c:2509 [inline]
 do_new_mount fs/namespace.c:2512 [inline]
 do_mount+0xea1/0x2bb0 fs/namespace.c:2841
 C_SYSC_mount fs/compat.c:195 [inline]
 compat_SyS_mount+0xd0/0x1070 fs/compat.c:160
 do_syscall_32_irqs_on arch/x86/entry/common.c:329 [inline]
 do_fast_syscall_32+0x3f2/0xf05 arch/x86/entry/common.c:391
 entry_SYSENTER_compat+0x51/0x60 arch/x86/entry/entry_64_compat.S:125
RIP: 0023:0xf7f46c79
RSP: 002b:00000000f774201c EFLAGS: 00000296 ORIG_RAX: 0000000000000015
RAX: ffffffffffffffda RBX: 0000000020907ff8 RCX: 0000000020058ffd
RDX: 0000000020c77ffa RSI: 0000000000000000 RDI: 0000000020de9000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Code: 3d eb ad c1 02 be c0 00 40 01 e8 21 d2 48 fe 48 89 c3 48 ba 00 00 00 00 00 fc ff df 48 83 c0 10 48 8d 7b 5c 48 89 f9 48 c1 e9 03 <0f> b6 0c 11 48 89 fa 83 e2 07 83 c2 03 38 ca 7c 04 84 c9 75 0e 
RIP: dax_alloc_inode+0x3b/0x70 drivers/dax/super.c:348 RSP: ffff8801d243f8d0
---[ end trace 543b2dab980d72b6 ]---

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2017/11/07 09:12 upstream e4880bc5dfb1 d49979f7 .config console log report ci-upstream-kasan-gce-386
* Struck through repros no longer work on HEAD.