syzbot


kernel BUG at mm/hugetlb.c:LINE!

Status: upstream: reported C repro on 2020/03/19 05:51
Reported-by: syzbot+e23d250c20e196754357@syzkaller.appspotmail.com
First crash: 929d, last: 752d

Fix bisection: failed (bisect log)
similar bugs (1):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream kernel BUG at mm/hugetlb.c:LINE! C done error 10 798d 911d 17/24 fixed on 2020/09/16 22:51
Patch testing requests:
Created Duration User Patch Repo Result
2022/08/29 13:27 16m (2) linux-4.19.y error
2022/08/29 01:27 13m linux-4.19.y error
2022/08/29 00:27 16m linux-4.19.y error

Sample crash report:
audit: type=1400 audit(1599876358.660:8): avc:  denied  { execmem } for  pid=6460 comm="syz-executor147" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1
overlayfs: upper fs does not support tmpfile.
overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off.
------------[ cut here ]------------
kernel BUG at mm/hugetlb.c:3385!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 6460 Comm: syz-executor147 Not tainted 4.19.144-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__unmap_hugepage_range+0x945/0xb10 mm/hugetlb.c:3385
Code: 4c 89 e2 e8 9d e4 91 ff 66 90 4c 89 f7 e8 c3 19 a2 05 e9 bc fa ff ff e8 d9 fd cc ff 0f 0b e8 d2 fd cc ff 0f 0b e8 cb fd cc ff <0f> 0b e8 c4 fd cc ff 48 8b 54 24 50 b9 01 00 00 00 48 89 ef 48 8b
RSP: 0018:ffff888089227a70 EFLAGS: 00010293
RAX: ffff888088c30400 RBX: ffffffff8b929c30 RCX: ffffffff819cad04
RDX: 0000000000000000 RSI: ffffffff819cb405 RDI: 0000000000000007
RBP: ffff8880a8f8f580 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000000 R12: 0000000020000000
R13: 0000000000001000 R14: ffff88809ab39260 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561416e1c210 CR3: 000000008e95e000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __unmap_hugepage_range_final+0x30/0x70 mm/hugetlb.c:3474
 unmap_single_vma+0x23a/0x300 mm/memory.c:1552
 unmap_vmas+0xa9/0x180 mm/memory.c:1586
 exit_mmap+0x2b9/0x530 mm/mmap.c:3091
 __mmput kernel/fork.c:1015 [inline]
 mmput+0x14e/0x4a0 kernel/fork.c:1036
 exit_mm kernel/exit.c:546 [inline]
 do_exit+0xab5/0x2b70 kernel/exit.c:874
 do_group_exit+0x125/0x310 kernel/exit.c:990
 __do_sys_exit_group kernel/exit.c:1001 [inline]
 __se_sys_exit_group kernel/exit.c:999 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:999
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x43f088
Code: Bad RIP value.
RSP: 002b:00007ffd385a3638 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043f088
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004be888 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 0000000000010012 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d0180 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace aaf6f66c29746148 ]---
RIP: 0010:__unmap_hugepage_range+0x945/0xb10 mm/hugetlb.c:3385
Code: 4c 89 e2 e8 9d e4 91 ff 66 90 4c 89 f7 e8 c3 19 a2 05 e9 bc fa ff ff e8 d9 fd cc ff 0f 0b e8 d2 fd cc ff 0f 0b e8 cb fd cc ff <0f> 0b e8 c4 fd cc ff 48 8b 54 24 50 b9 01 00 00 00 48 89 ef 48 8b
RSP: 0018:ffff888089227a70 EFLAGS: 00010293
RAX: ffff888088c30400 RBX: ffffffff8b929c30 RCX: ffffffff819cad04
RDX: 0000000000000000 RSI: ffffffff819cb405 RDI: 0000000000000007
RBP: ffff8880a8f8f580 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000000 R12: 0000000020000000
R13: 0000000000001000 R14: ffff88809ab39260 R15: 0000000000000000
FS:  00000000020d9880(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000043f05e CR3: 000000008e95e000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (3):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-19 2020/09/12 02:07 linux-4.19.y 67957f12548c 79fb24e2 .config log report syz C
ci2-linux-4-19 2020/03/23 22:02 linux-4.19.y 14cfdbd39e31 84f999d6 .config log report syz C
ci2-linux-4-19 2020/03/19 05:50 linux-4.19.y 93556fb211fa 2c31c529 .config log report syz C
* Struck through repros no longer work on HEAD.