syzbot


general protection fault in current_umask

Status: upstream: reported C repro on 2024/09/17 07:03
Reported-by: syzbot+2c4104481f4e884738e7@syzkaller.appspotmail.com
First crash: 11d, last: 11d

Sample crash report:
fscrypt: AES-256-CTS-CBC using implementation "cts(cbc-aes-aesni)"
fscrypt: AES-256-XTS using implementation "xts-aes-aesni"
incfs: Can't find or create .index dir in ./file0
incfs: mount failed -22
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 PID: 288 Comm: syz-executor296 Not tainted 5.10.225-syzkaller-00513-g8d23314f588a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:current_umask+0x49/0x70 fs/fs_struct.c:158
Code: 81 c3 c0 07 00 00 48 89 d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 b5 a2 e9 ff 48 8b 1b 48 83 c3 0c 48 89 d8 48 c1 e8 03 <42> 0f b6 04 30 84 c0 75 07 8b 03 5b 41 5e 5d c3 89 d9 80 e1 07 80
RSP: 0018:ffffc90000b374b8 EFLAGS: 00010203
RAX: 0000000000000001 RBX: 000000000000000c RCX: ffff888120a20000
RDX: 0000000000000000 RSI: ffffffff8686a330 RDI: 0000000000000000
RBP: ffffc90000b374c8 R08: 0000000000000007 R09: ffffffff81cb18f5
R10: 0000000000000002 R11: ffff888120a20000 R12: dffffc0000000000
R13: 1ffff92000166eb4 R14: dffffc0000000000 R15: ffff88810fdbce60
FS:  0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056157b3a0048 CR3: 000000010c9eb000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 posix_acl_create+0x169/0x400 fs/posix_acl.c:597
 ext4_init_acl+0xf3/0x400 fs/ext4/acl.c:279
 __ext4_new_inode+0x2f6f/0x3ee0 fs/ext4/ialloc.c:1319
 ext4_mknod+0x267/0x530 fs/ext4/namei.c:2856
 vfs_mknod+0x53f/0x610 fs/namei.c:3693
 vfs_whiteout include/linux/fs.h:1835 [inline]
 ovl_do_whiteout fs/overlayfs/overlayfs.h:229 [inline]
 ovl_whiteout fs/overlayfs/dir.c:77 [inline]
 ovl_cleanup_and_whiteout+0x1b1/0x580 fs/overlayfs/dir.c:117
 ovl_remove_and_whiteout fs/overlayfs/dir.c:795 [inline]
 ovl_do_remove+0x72a/0xc90 fs/overlayfs/dir.c:922
 ovl_rmdir+0x1a/0x20 fs/overlayfs/dir.c:956
 vfs_rmdir+0x2b7/0x3f0 fs/namei.c:3852
 incfs_kill_sb+0x108/0x220 fs/incfs/vfs.c:1973
 deactivate_locked_super+0xad/0x110 fs/super.c:335
 deactivate_super+0xbe/0xf0 fs/super.c:366
 cleanup_mnt+0x45c/0x510 fs/namespace.c:1118
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1125
 task_work_run+0x129/0x190 kernel/task_work.c:189
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0xc83/0x2a50 kernel/exit.c:863
 do_group_exit+0x141/0x310 kernel/exit.c:985
 __do_sys_exit_group kernel/exit.c:996 [inline]
 __se_sys_exit_group kernel/exit.c:994 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:994
 do_syscall_64+0x34/0x70
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7efd57875809
Code: Unable to access opcode bytes at RIP 0x7efd578757df.
RSP: 002b:00007ffc09bc6ac8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007efd57875809
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001
RBP: 00007efd578f12b0 R08: ffffffffffffffb8 R09: 00007efd578c583c
R10: 0000000000000000 R11: 0000000000000246 R12: 00007efd578f12b0
R13: 0000000000000000 R14: 00007efd578f2020 R15: 00007efd57843b40
Modules linked in:
---[ end trace 8ec9e32bf0e3dd86 ]---
RIP: 0010:current_umask+0x49/0x70 fs/fs_struct.c:158
Code: 81 c3 c0 07 00 00 48 89 d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 b5 a2 e9 ff 48 8b 1b 48 83 c3 0c 48 89 d8 48 c1 e8 03 <42> 0f b6 04 30 84 c0 75 07 8b 03 5b 41 5e 5d c3 89 d9 80 e1 07 80
RSP: 0018:ffffc90000b374b8 EFLAGS: 00010203
RAX: 0000000000000001 RBX: 000000000000000c RCX: ffff888120a20000
RDX: 0000000000000000 RSI: ffffffff8686a330 RDI: 0000000000000000
RBP: ffffc90000b374c8 R08: 0000000000000007 R09: ffffffff81cb18f5
R10: 0000000000000002 R11: ffff888120a20000 R12: dffffc0000000000
R13: 1ffff92000166eb4 R14: dffffc0000000000 R15: ffff88810fdbce60
FS:  0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056157b3a0048 CR3: 000000000660f000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	81 c3 c0 07 00 00    	add    $0x7c0,%ebx
   6:	48 89 d8             	mov    %rbx,%rax
   9:	48 c1 e8 03          	shr    $0x3,%rax
   d:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1)
  12:	74 08                	je     0x1c
  14:	48 89 df             	mov    %rbx,%rdi
  17:	e8 b5 a2 e9 ff       	call   0xffe9a2d1
  1c:	48 8b 1b             	mov    (%rbx),%rbx
  1f:	48 83 c3 0c          	add    $0xc,%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 30       	movzbl (%rax,%r14,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	75 07                	jne    0x3a
  33:	8b 03                	mov    (%rbx),%eax
  35:	5b                   	pop    %rbx
  36:	41 5e                	pop    %r14
  38:	5d                   	pop    %rbp
  39:	c3                   	ret
  3a:	89 d9                	mov    %ebx,%ecx
  3c:	80 e1 07             	and    $0x7,%cl
  3f:	80                   	.byte 0x80

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/17 09:58 android13-5.10-lts 8d23314f588a c673ca06 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-10 general protection fault in current_umask
2024/09/17 08:58 android13-5.10-lts 8d23314f588a c673ca06 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-10 general protection fault in current_umask
2024/09/17 07:59 android13-5.10-lts 8d23314f588a c673ca06 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-10 general protection fault in current_umask
2024/09/17 06:59 android13-5.10-lts 8d23314f588a c673ca06 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-android-5-10 general protection fault in current_umask
2024/09/17 05:58 android13-5.10-lts 8d23314f588a c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 general protection fault in current_umask
* Struck through repros no longer work on HEAD.