Message-ID: <68d26261.a70a0220.4f78.0004.GAE@google.com>
Date: Tue, 23 Sep 2025 02:03:29 -0700
From: syzbot <syzbot+62edf7e27b2e8f754525@...kaller.appspotmail.com>
To: david@...hat.com, linux-fsdevel@...r.kernel.org, 
	linux-kernel@...r.kernel.org, linux-mm@...ck.org, muchun.song@...ux.dev, 
	osalvador@...e.de, syzkaller-bugs@...glegroups.com
Subject: [syzbot] [fs?] [mm?] WARNING: bad unlock balance in hugetlb_vmdelete_list

Hello,

syzbot found the following issue on:

HEAD commit:    846bd2225ec3 Add linux-next specific files for 20250919
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=13263534580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=135377594f35b576
dashboard link: https://syzkaller.appspot.com/bug?extid=62edf7e27b2e8f754525
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14a118e2580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17e204e2580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c53d48022f8a/disk-846bd222.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/483534e784c8/vmlinux-846bd222.xz
kernel image: https://storage.googleapis.com/syzbot-assets/721b36eec9b3/bzImage-846bd222.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+62edf7e27b2e8f754525@...kaller.appspotmail.com

=====================================
WARNING: bad unlock balance detected!
syzkaller #0 Not tainted
-------------------------------------
syz.0.8060/30977 is trying to release lock (&vma_lock->rw_sema) at:
[<ffffffff82903959>] hugetlb_vmdelete_list+0x179/0x1c0 fs/hugetlbfs/inode.c:501
but there are no more locks to release!

other info that might help us debug this:
3 locks held by syz.0.8060/30977:
 #0: ffff88807d8da420 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:508
 #1: ffff888034404648 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: inode_lock_killable include/linux/fs.h:985 [inline]
 #1: ffff888034404648 (&sb->s_type->i_mutex_key#20){+.+.}-{4:4}, at: do_truncate+0x171/0x220 fs/open.c:63
 #2: ffff888034404918 (&hugetlbfs_i_mmap_rwsem_key){+.+.}-{4:4}, at: i_mmap_lock_write include/linux/fs.h:548 [inline]
 #2: ffff888034404918 (&hugetlbfs_i_mmap_rwsem_key){+.+.}-{4:4}, at: hugetlb_vmtruncate fs/hugetlbfs/inode.c:639 [inline]
 #2: ffff888034404918 (&hugetlbfs_i_mmap_rwsem_key){+.+.}-{4:4}, at: hugetlbfs_setattr+0x489/0x6d0 fs/hugetlbfs/inode.c:879

stack backtrace:
CPU: 1 UID: 0 PID: 30977 Comm: syz.0.8060 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_unlock_imbalance_bug+0xdc/0xf0 kernel/locking/lockdep.c:5298
 __lock_release kernel/locking/lockdep.c:5537 [inline]
 lock_release+0x269/0x3e0 kernel/locking/lockdep.c:5889
 up_write+0x2d/0x420 kernel/locking/rwsem.c:1642
 hugetlb_vmdelete_list+0x179/0x1c0 fs/hugetlbfs/inode.c:501
 hugetlb_vmtruncate fs/hugetlbfs/inode.c:641 [inline]
 hugetlbfs_setattr+0x4d1/0x6d0 fs/hugetlbfs/inode.c:879
 notify_change+0xc1a/0xf40 fs/attr.c:546
 do_truncate+0x1a4/0x220 fs/open.c:68
 handle_truncate fs/namei.c:3516 [inline]
 do_open fs/namei.c:3899 [inline]
 path_openat+0x306c/0x3830 fs/namei.c:4054
 do_filp_open+0x1fa/0x410 fs/namei.c:4081
 do_sys_openat2+0x121/0x1c0 fs/open.c:1435
 do_sys_open fs/open.c:1450 [inline]
 __do_sys_open fs/open.c:1458 [inline]
 __se_sys_open fs/open.c:1454 [inline]
 __x64_sys_open+0x11e/0x150 fs/open.c:1454
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdea5b8eec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fdea6945038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fdea5de5fa0 RCX: 00007fdea5b8eec9
RDX: 0000000000000100 RSI: 000000000014927e RDI: 0000200000000340
RBP: 00007fdea5c11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdea5de6038 R14: 00007fdea5de5fa0 R15: 00007ffe42e704f8
 </TASK>
------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON((rwsem_owner(sem) != current) && !rwsem_test_oflags(sem, RWSEM_NONSPINNABLE)): count = 0x0, magic = 0xffff8880295a5408, owner = 0x1, curr 0xffff8880260d9e40, list empty
WARNING: kernel/locking/rwsem.c:1381 at __up_write kernel/locking/rwsem.c:1380 [inline], CPU#1: syz.0.8060/30977
WARNING: kernel/locking/rwsem.c:1381 at up_write+0x3a2/0x420 kernel/locking/rwsem.c:1643, CPU#1: syz.0.8060/30977
Modules linked in:
CPU: 1 UID: 0 PID: 30977 Comm: syz.0.8060 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__up_write kernel/locking/rwsem.c:1380 [inline]
RIP: 0010:up_write+0x3a2/0x420 kernel/locking/rwsem.c:1643
Code: d0 48 c7 c7 00 f0 aa 8b 48 c7 c6 20 f2 aa 8b 48 8b 14 24 4c 89 f1 4d 89 e0 4c 8b 4c 24 08 41 52 e8 b3 39 e6 ff 48 83 c4 08 90 <0f> 0b 90 90 e9 6d fd ff ff 48 c7 c1 74 0b e5 8f 80 e1 07 80 c1 03
RSP: 0018:ffffc900051076c8 EFLAGS: 00010282
RAX: b37f99c54516e500 RBX: ffff8880295a5408 RCX: ffff8880260d9e40
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: dffffc0000000000 R08: ffffc900051073e7 R09: 1ffff92000a20e7c
R10: dffffc0000000000 R11: fffff52000a20e7d R12: 0000000000000001
R13: ffff8880295a5460 R14: ffff8880295a5408 R15: 1ffff110052b4a82
FS:  00007fdea69456c0(0000) GS:ffff8881258a2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdea51fed58 CR3: 00000000779ba000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 hugetlb_vmdelete_list+0x179/0x1c0 fs/hugetlbfs/inode.c:501
 hugetlb_vmtruncate fs/hugetlbfs/inode.c:641 [inline]
 hugetlbfs_setattr+0x4d1/0x6d0 fs/hugetlbfs/inode.c:879
 notify_change+0xc1a/0xf40 fs/attr.c:546
 do_truncate+0x1a4/0x220 fs/open.c:68
 handle_truncate fs/namei.c:3516 [inline]
 do_open fs/namei.c:3899 [inline]
 path_openat+0x306c/0x3830 fs/namei.c:4054
 do_filp_open+0x1fa/0x410 fs/namei.c:4081
 do_sys_openat2+0x121/0x1c0 fs/open.c:1435
 do_sys_open fs/open.c:1450 [inline]
 __do_sys_open fs/open.c:1458 [inline]
 __se_sys_open fs/open.c:1454 [inline]
 __x64_sys_open+0x11e/0x150 fs/open.c:1454
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdea5b8eec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fdea6945038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fdea5de5fa0 RCX: 00007fdea5b8eec9
RDX: 0000000000000100 RSI: 000000000014927e RDI: 0000200000000340
RBP: 00007fdea5c11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdea5de6038 R14: 00007fdea5de5fa0 R15: 00007ffe42e704f8
 </TASK>


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
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If the report is already addressed, let syzbot know by replying with:
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If you want to overwrite report's subsystems, reply with:
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