syzbot


general protection fault in ext4_write_begin

Status: auto-obsoleted due to no activity on 2023/06/06 13:58
Subsystems: ext4
[Documentation on labels]
Reported-by: syzbot+30250de45664aed70a33@syzkaller.appspotmail.com
First crash: 411d, last: 405d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [ext4?] general protection fault in ext4_write_begin 0 (1) 2023/04/18 05:19

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
CPU: 0 PID: 25545 Comm: syz-executor.5 Not tainted 6.3.0-rc7-next-20230418-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
RIP: 0010:folio_get_private include/linux/mm_types.h:419 [inline]
RIP: 0010:ext4_write_begin+0x2e3/0x1020 fs/ext4/inode.c:1186
Code: f0 00 00 00 e8 6e 9d 83 ff 48 85 c0 49 89 c5 0f 84 36 0b 00 00 e8 fd cf 56 ff 49 8d 45 28 48 89 84 24 80 00 00 00 48 c1 e8 03 <42> 80 3c 30 00 0f 85 eb 0c 00 00 49 83 7d 28 00 0f 84 ba 09 00 00
RSP: 0018:ffffc9001475f5a0 EFLAGS: 00010207
RAX: 0000000000000003 RBX: 0000000000000000 RCX: ffffc9000ba01000
RDX: 0000000000040000 RSI: ffffffff822cb553 RDI: ffffffff8c8eef10
RBP: ffff88802b3f8380 R08: 0000000000000001 R09: ffffffff8c8eef13
R10: fffffbfff191dde2 R11: 0000000000000000 R12: ffff88802b3f8000
R13: fffffffffffffff4 R14: dffffc0000000000 R15: ffff88803d1b66b0
FS:  00007f5897cab700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33328000 CR3: 0000000078549000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ext4_da_write_begin+0x223/0x8b0 fs/ext4/inode.c:2917
 pagecache_write.isra.0+0x244/0x340 fs/ext4/verity.c:83
 ext4_write_verity_descriptor fs/ext4/verity.c:183 [inline]
 ext4_end_enable_verity+0x1e5/0x6d0 fs/ext4/verity.c:208
 enable_verity+0x700/0x9d0 fs/verity/enable.c:284
 fsverity_ioctl_enable+0x404/0x560 fs/verity/enable.c:385
 __ext4_ioctl+0x23c6/0x4b00 fs/ext4/ioctl.c:1574
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x197/0x210 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f5896e8c169
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007f5897cab168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f5896fabf80 RCX: 00007f5896e8c169
RDX: 0000000020000240 RSI: 0000000040806685 RDI: 0000000000000003
RBP: 00007f5897cab1d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ffcbadc1b8f R14: 00007f5897cab300 R15: 0000000000022000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:folio_get_private include/linux/mm_types.h:419 [inline]
RIP: 0010:ext4_write_begin+0x2e3/0x1020 fs/ext4/inode.c:1186
Code: f0 00 00 00 e8 6e 9d 83 ff 48 85 c0 49 89 c5 0f 84 36 0b 00 00 e8 fd cf 56 ff 49 8d 45 28 48 89 84 24 80 00 00 00 48 c1 e8 03 <42> 80 3c 30 00 0f 85 eb 0c 00 00 49 83 7d 28 00 0f 84 ba 09 00 00
RSP: 0018:ffffc9001475f5a0 EFLAGS: 00010207
RAX: 0000000000000003 RBX: 0000000000000000 RCX: ffffc9000ba01000
RDX: 0000000000040000 RSI: ffffffff822cb553 RDI: ffffffff8c8eef10
RBP: ffff88802b3f8380 R08: 0000000000000001 R09: ffffffff8c8eef13
R10: fffffbfff191dde2 R11: 0000000000000000 R12: ffff88802b3f8000
R13: fffffffffffffff4 R14: dffffc0000000000 R15: ffff88803d1b66b0
FS:  00007f5897cab700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3332d000 CR3: 0000000078549000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	f0 00 00             	lock add %al,(%rax)
   3:	00 e8                	add    %ch,%al
   5:	6e                   	outsb  %ds:(%rsi),(%dx)
   6:	9d                   	popfq
   7:	83 ff 48             	cmp    $0x48,%edi
   a:	85 c0                	test   %eax,%eax
   c:	49 89 c5             	mov    %rax,%r13
   f:	0f 84 36 0b 00 00    	je     0xb4b
  15:	e8 fd cf 56 ff       	callq  0xff56d017
  1a:	49 8d 45 28          	lea    0x28(%r13),%rax
  1e:	48 89 84 24 80 00 00 	mov    %rax,0x80(%rsp)
  25:	00
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1) <-- trapping instruction
  2f:	0f 85 eb 0c 00 00    	jne    0xd20
  35:	49 83 7d 28 00       	cmpq   $0x0,0x28(%r13)
  3a:	0f 84 ba 09 00 00    	je     0x9fa

Crashes (12):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/04/19 12:12 linux-next 67d5d9f013d6 94b4184e .config console log report info ci-upstream-linux-next-kasan-gce-root general protection fault in ext4_write_begin
2023/04/19 03:15 linux-next 67d5d9f013d6 d931e9f0 .config console log report info ci-upstream-linux-next-kasan-gce-root general protection fault in ext4_write_begin
2023/04/19 00:49 linux-next 67d5d9f013d6 d931e9f0 .config console log report info ci-upstream-linux-next-kasan-gce-root general protection fault in ext4_write_begin
2023/04/17 17:23 linux-next d3f2cd248191 c6ec7083 .config console log report info ci-upstream-linux-next-kasan-gce-root general protection fault in ext4_write_begin
2023/04/17 04:05 linux-next d3f2cd248191 ec410564 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ext4_write_begin
2023/04/17 01:12 linux-next d3f2cd248191 ec410564 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ext4_write_begin
2023/04/16 12:18 linux-next d3f2cd248191 ec410564 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ext4_write_begin
2023/04/16 11:00 linux-next d3f2cd248191 ec410564 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ext4_write_begin
2023/04/15 20:51 linux-next d3f2cd248191 ec410564 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ext4_write_begin
2023/04/15 16:25 linux-next d3f2cd248191 ec410564 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ext4_write_begin
2023/04/14 16:39 linux-next e3342532ecd3 3cfcaa1b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ext4_write_begin
2023/04/14 05:17 linux-next e3342532ecd3 3cfcaa1b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ext4_write_begin
* Struck through repros no longer work on HEAD.