Re: [syzbot] [afs?] BUG: sleeping function called from invalid context in __alloc_frozen_pages_noprof

[syzbot <syzbot+3b6c5c6a1d0119b687a1@syzkaller.appspotmail.com>]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
WARNING in inode_set_cached_link

------------[ cut here ]------------
bad length passed for symlink [/tmp/syz-imagegen2884317625/\b] (got 39, expected 29)
WARNING: CPU: 0 PID: 6579 at ./include/linux/fs.h:803 inode_set_cached_link+0xd0/0x110 include/linux/fs.h:802
Modules linked in:
CPU: 0 UID: 0 PID: 6579 Comm: syz-executor Not tainted 6.14.0-rc4-syzkaller-00172-g1d0b929fc070-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:inode_set_cached_link+0xd0/0x110 include/linux/fs.h:802
Code: 41 5f 5d c3 cc cc cc cc e8 3d ef 44 ff c6 05 e0 41 a8 0d 01 90 48 c7 c7 e0 23 3e 8c 4c 89 f6 44 89 fa 89 e9 e8 21 79 03 ff 90 <0f> 0b 90 90 e9 6a ff ff ff 89 f9 80 e1 07 80 c1 03 38 c1 7c a1 e8
RSP: 0018:ffffc90003667698 EFLAGS: 00010246
RAX: 720c93d201fc4800 RBX: ffff888063c302b0 RCX: ffff88807b148000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 000000000000001d R08: ffffffff81819472 R09: 1ffff110170c519a
R10: dffffc0000000000 R11: ffffed10170c519b R12: ffff888063c302b0
R13: dffffc0000000000 R14: ffff888063c30000 R15: 0000000000000027
FS:  000055558945a500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe2a3a0da8 CR3: 0000000033d6c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __ext4_iget+0x2ea4/0x3f30 fs/ext4/inode.c:5012
 ext4_lookup+0x3e3/0x750 fs/ext4/namei.c:1813
 __lookup_slow+0x296/0x400 fs/namei.c:1793
 lookup_slow+0x53/0x70 fs/namei.c:1810
 walk_component+0x2ea/0x410 fs/namei.c:2114
 lookup_last fs/namei.c:2612 [inline]
 path_lookupat+0x16f/0x450 fs/namei.c:2636
 filename_lookup+0x2a3/0x670 fs/namei.c:2665
 user_path_at+0x3a/0x60 fs/namei.c:3072
 ksys_umount fs/namespace.c:2071 [inline]
 __do_sys_umount fs/namespace.c:2079 [inline]
 __se_sys_umount fs/namespace.c:2077 [inline]
 __x64_sys_umount+0xf1/0x170 fs/namespace.c:2077
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdcbc38e497
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffe2a3a1558 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 00007fdcbc40e08c RCX: 00007fdcbc38e497
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe2a3a1610
RBP: 00007ffe2a3a1610 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe2a3a2700
R13: 00007fdcbc40e08c R14: 000000000001bcfe R15: 00007ffe2a3a48c0
 </TASK>


Tested on:

commit:         1d0b929f afs: Change dynroot to create contents on dem..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=17fb7804580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b1debf8c2c3d28b1
dashboard link: https://syzkaller.appspot.com/bug?extid=3b6c5c6a1d0119b687a1
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1514864c580000