[syzbot] [afs?] [ntfs3?] BUG: sleeping function called from invalid context in ovl_cache_entry_new

[syzbot <syzbot+54e6c2176ba76c56217e@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    2df0c02dab82 x86 boot build: make git ignore stale 'tools'..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=138f0a4c580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=5f1762820c18874b
dashboard link: https://syzkaller.appspot.com/bug?extid=54e6c2176ba76c56217e
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=178f0a4c580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14182bb0580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7fe089500003/disk-2df0c02d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d8df5abbd7c5/vmlinux-2df0c02d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/09d23e93d3a8/bzImage-2df0c02d.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/586c05b92249/mount_0.gz

The issue was bisected to:

commit 1d0b929fc070b4115403a0a6206a0c6a62dd61f5
Author: David Howells <dhowells@redhat.com>
Date:   Mon Feb 24 09:52:58 2025 +0000

    afs: Change dynroot to create contents on demand

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=1747aa4c580000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=14c7aa4c580000
console output: https://syzkaller.appspot.com/x/log.txt?x=10c7aa4c580000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+54e6c2176ba76c56217e@syzkaller.appspotmail.com
Fixes: 1d0b929fc070 ("afs: Change dynroot to create contents on demand")

BUG: sleeping function called from invalid context at ./include/linux/sched/mm.h:321
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 5821, name: syz-executor365
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
4 locks held by syz-executor365/5821:
 #0: ffff888032b155f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x310 fs/file.c:1213
 #1: ffff888077c90cf8 (&ovl_i_mutex_dir_key[depth]){++++}-{4:4}, at: wrap_directory_iterator+0x5a/0xd0 fs/readdir.c:54
 #2: ffff88807d2c0148 (&type->i_mutex_dir_key#6){++++}-{4:4}, at: iterate_dir+0x4a6/0x760 fs/readdir.c:101
 #3: ffffffff8eb3a760 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #3: ffffffff8eb3a760 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #3: ffffffff8eb3a760 (rcu_read_lock){....}-{1:3}, at: afs_dynroot_readdir+0x466/0xbe0 fs/afs/dynroot.c:351
CPU: 0 UID: 0 PID: 5821 Comm: syz-executor365 Not tainted 6.14.0-syzkaller-01103-g2df0c02dab82 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 __might_resched+0x558/0x6c0 kernel/sched/core.c:8798
 might_alloc include/linux/sched/mm.h:321 [inline]
 slab_pre_alloc_hook mm/slub.c:4089 [inline]
 slab_alloc_node mm/slub.c:4167 [inline]
 __do_kmalloc_node mm/slub.c:4317 [inline]
 __kmalloc_noprof+0xd0/0x4d0 mm/slub.c:4330
 kmalloc_noprof include/linux/slab.h:906 [inline]
 ovl_cache_entry_new+0x39/0x7b0 fs/overlayfs/readdir.c:152
 ovl_cache_entry_add_rb fs/overlayfs/readdir.c:188 [inline]
 ovl_fill_merge+0x416/0x830 fs/overlayfs/readdir.c:266
 dir_emit include/linux/fs.h:3853 [inline]
 afs_dynroot_readdir_cells fs/afs/dynroot.c:310 [inline]
 afs_dynroot_readdir+0x814/0xbe0 fs/afs/dynroot.c:352
 iterate_dir+0x5a9/0x760 fs/readdir.c:108
 ovl_dir_read+0xfe/0x570 fs/overlayfs/readdir.c:313
 ovl_dir_read_merged+0x315/0x5e0 fs/overlayfs/readdir.c:369
 ovl_cache_get fs/overlayfs/readdir.c:422 [inline]
 ovl_iterate+0x1196/0x21c0 fs/overlayfs/readdir.c:783
 wrap_directory_iterator+0x91/0xd0 fs/readdir.c:65
 iterate_dir+0x5a9/0x760 fs/readdir.c:108
 __do_sys_getdents fs/readdir.c:322 [inline]
 __se_sys_getdents+0x1ff/0x4e0 fs/readdir.c:308
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7c82f020f9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 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:00007fff5a9e9b58 EFLAGS: 00000246 ORIG_RAX: 000000000000004e
RAX: ffffffffffffffda RBX: 00007fff5a9e9c20 RCX: 00007f7c82f020f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000000000


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