syzbot


general protection fault in ext4_xattr_set_entry

Status: closed as invalid on 2022/09/26 18:30
Reported-by: syzbot+70627ce76b4994c2e0b4@syzkaller.appspotmail.com
First crash: 90d, last: 76d

Cause bisection: failed (bisect log)
similar bugs (6):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 general protection fault in ext4_xattr_set_entry (2) C error 74 20h16m 53d 0/2 upstream: reported C repro on 2022/10/15 11:08
linux-4.19 KASAN: use-after-free Read in ext4_xattr_set_entry (2) C done 7 451d 909d 1/1 fixed on 2021/10/13 07:23
upstream KASAN: use-after-free Read in ext4_xattr_set_entry (5) 2 135d 193d 0/24 auto-obsoleted due to no activity on 2022/11/22 17:19
android-54 KASAN: out-of-bounds Read in ext4_xattr_set_entry C 1 625d 625d 0/2 upstream: reported C repro on 2021/03/21 22:06
upstream KASAN: use-after-free Read in ext4_xattr_set_entry (4) C error done 21 289d 676d 22/24 fixed on 2022/03/28 10:17
linux-4.14 KASAN: out-of-bounds Read in ext4_xattr_set_entry C error 2 90d 604d 0/1 upstream: reported C repro on 2021/04/12 14:20
Patch testing requests:
Created Duration User Patch Repo Result
2022/09/24 13:14 12m tadeusz.struk@linaro.org git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git linux-5.13.y report log
2022/09/24 02:12 8m tadeusz.struk@linaro.org git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git linux-5.14.y report log
2022/09/23 21:11 9m tadeusz.struk@linaro.org patch android12-5.10-lts report log
2022/09/23 20:13 8m tadeusz.struk@linaro.org patch android12-5.10-lts report log
2022/09/23 17:49 16m tadeusz.struk@linaro.org git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git linux-5.15.y OK log
2022/09/22 23:27 8m tadeusz.struk@linaro.org patch android12-5.10-lts report log
2022/09/22 22:13 8m tadeusz.struk@linaro.org patch android12-5.10-lts report log
2022/09/22 21:47 9m tadeusz.struk@linaro.org patch android12-5.10-lts report log
2022/09/22 21:28 9m tadeusz.struk@linaro.org patch android12-5.10-lts report log
2022/09/22 17:59 8m tadeusz.struk@linaro.org android12-5.10-lts report log
2022/09/15 21:18 8m tadeusz.struk@linaro.org patch android12-5.10-lts report log
2022/09/15 20:34 8m tadeusz.struk@linaro.org patch android12-5.10-lts report log
2022/09/09 00:55 7m tadeusz.struk@linaro.org https://android.googlesource.com/kernel/common android12-5.10 report log
2022/09/08 23:55 7m tadeusz.struk@linaro.org https://android.googlesource.com/kernel/common android12-5.10 report log
2022/09/08 17:55 17m tadeusz.struk@linaro.org git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master OK log
2022/09/08 17:54 7m tadeusz.struk@linaro.org android12-5.10-lts report log

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 PID: 371 Comm: syz-executor144 Not tainted 5.10.140-syzkaller-00825-g59390358870a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
RIP: 0010:ext4_xattr_set_entry+0x4ad/0x37e0 fs/ext4/xattr.c:1586
Code: 00 00 48 89 d8 48 c1 e8 03 48 89 84 24 28 01 00 00 42 80 3c 20 00 74 08 48 89 df e8 1d 97 ba ff 4c 8b 33 4c 89 f0 48 c1 e8 03 <42> 8a 04 20 84 c0 0f 85 46 2d 00 00 4c 89 f8 48 2b 44 24 18 48 89
RSP: 0018:ffffc90000b873c0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffc90000b877c0 RCX: ffff8881067a8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000001c
RBP: ffffc90000b87658 R08: ffffffff81ec6059 R09: ffffed1021d6c76d
R10: ffffed1021d6c76d R11: 1ffff11021d6c76c R12: dffffc0000000000
R13: 1ffff92000170ef2 R14: 0000000000000000 R15: 0000000000000000
FS:  0000555555deb3c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555555dfc728 CR3: 000000011e012000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ext4_xattr_ibody_set+0x7c/0x2a0 fs/ext4/xattr.c:2227
 ext4_xattr_set_handle+0xc5d/0x15a0 fs/ext4/xattr.c:2384
 ext4_initxattrs+0xb2/0x120 fs/ext4/xattr_security.c:43
 security_inode_init_security+0x26c/0x3c0 security/security.c:1033
 ext4_init_security+0x34/0x40 fs/ext4/xattr_security.c:57
 __ext4_new_inode+0x3648/0x4530 fs/ext4/ialloc.c:1322
 ext4_mkdir+0x3b3/0xbb0 fs/ext4/namei.c:2947
 vfs_mkdir+0x435/0x610 fs/namei.c:3729
 do_mkdirat+0x1b6/0x2d0 fs/namei.c:3752
 __do_sys_mkdir fs/namei.c:3768 [inline]
 __se_sys_mkdir fs/namei.c:3766 [inline]
 __x64_sys_mkdir+0x60/0x70 fs/namei.c:3766
 do_syscall_64+0x34/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xc6
RIP: 0033:0x7fb59be693d7
Code: 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 53 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:00007ffc053936d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 0000000000004e46 RCX: 00007fb59be693d7
RDX: 0000000000000000 RSI: 00000000000001ff RDI: 00007ffc05393710
RBP: 0000000000000175 R08: 0000000000000000 R09: 0000000000000003
R10: 00007ffc05393477 R11: 0000000000000206 R12: 00007ffc053936fc
R13: 00007ffc05393730 R14: 00007ffc05393710 R15: 0000000000000001
Modules linked in:
---[ end trace 58fa3ede2a53b241 ]---
RIP: 0010:ext4_xattr_set_entry+0x4ad/0x37e0 fs/ext4/xattr.c:1586
Code: 00 00 48 89 d8 48 c1 e8 03 48 89 84 24 28 01 00 00 42 80 3c 20 00 74 08 48 89 df e8 1d 97 ba ff 4c 8b 33 4c 89 f0 48 c1 e8 03 <42> 8a 04 20 84 c0 0f 85 46 2d 00 00 4c 89 f8 48 2b 44 24 18 48 89
RSP: 0018:ffffc90000b873c0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffc90000b877c0 RCX: ffff8881067a8000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000001c
RBP: ffffc90000b87658 R08: ffffffff81ec6059 R09: ffffed1021d6c76d
R10: ffffed1021d6c76d R11: 1ffff11021d6c76c R12: dffffc0000000000
R13: 1ffff92000170ef2 R14: 0000000000000000 R15: 0000000000000000
FS:  0000555555deb3c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555555dfc728 CR3: 000000011e012000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	48 89 d8             	mov    %rbx,%rax
   5:	48 c1 e8 03          	shr    $0x3,%rax
   9:	48 89 84 24 28 01 00 	mov    %rax,0x128(%rsp)
  10:	00
  11:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1)
  16:	74 08                	je     0x20
  18:	48 89 df             	mov    %rbx,%rdi
  1b:	e8 1d 97 ba ff       	callq  0xffba973d
  20:	4c 8b 33             	mov    (%rbx),%r14
  23:	4c 89 f0             	mov    %r14,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 8a 04 20          	mov    (%rax,%r12,1),%al <-- trapping instruction
  2e:	84 c0                	test   %al,%al
  30:	0f 85 46 2d 00 00    	jne    0x2d7c
  36:	4c 89 f8             	mov    %r15,%rax
  39:	48 2b 44 24 18       	sub    0x18(%rsp),%rax
  3e:	48                   	rex.W
  3f:	89                   	.byte 0x89

Crashes (2):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-android-5-10 2022/09/08 14:44 android12-5.10-lts 59390358870a f3027468 .config log report syz C general protection fault in ext4_xattr_set_entry
ci2-android-5-10 2022/09/08 14:26 android12-5.10-lts 59390358870a f3027468 .config log report info general protection fault in ext4_xattr_set_entry
* Struck through repros no longer work on HEAD.