Re: [syzbot] [bpf?] WARNING: locking bug in bpf_map_put

[syzbot <syzbot+d2adb332fe371b0595e3@syzkaller.appspotmail.com>]

Hello,

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

=============================
[ BUG: Invalid wait context ]
6.12.0-rc5-syzkaller-00299-g11066801dd4b-dirty #0 Not tainted
-----------------------------
syz.0.15/6617 is trying to lock:
ffff8880b8643cc0 (&c->lock){-.-.}-{3:3}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
ffff8880b8643cc0 (&c->lock){-.-.}-{3:3}, at: ___slab_alloc+0x265/0x14b0 mm/slub.c:3695
other info that might help us debug this:
context-{5:5}
2 locks held by syz.0.15/6617:
 #0: ffff8880b863d678 (lock){+.+.}-{3:3}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
 #0: ffff8880b863d678 (lock){+.+.}-{3:3}, at: __radix_tree_preload+0x80/0x860 lib/radix-tree.c:334
 #1: ffffffff8e9b57d8 (map_idr_lock){+...}-{2:2}, at: bpf_map_alloc_id+0x21/0xe0 kernel/bpf/syscall.c:355
stack backtrace:
CPU: 0 UID: 0 PID: 6617 Comm: syz.0.15 Not tainted 6.12.0-rc5-syzkaller-00299-g11066801dd4b-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_lock_invalid_wait_context kernel/locking/lockdep.c:4802 [inline]
 check_wait_context kernel/locking/lockdep.c:4874 [inline]
 __lock_acquire+0x15a8/0x2100 kernel/locking/lockdep.c:5152
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
 local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
 ___slab_alloc+0x27e/0x14b0 mm/slub.c:3695
 __slab_alloc+0x58/0xa0 mm/slub.c:3908
 __slab_alloc_node mm/slub.c:3961 [inline]
 slab_alloc_node mm/slub.c:4122 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x2a0 mm/slub.c:4141
 radix_tree_node_alloc+0x8b/0x3c0 lib/radix-tree.c:276
 idr_get_free+0x296/0xab0 lib/radix-tree.c:1506
 idr_alloc_u32+0x195/0x330 lib/idr.c:46
 idr_alloc_cyclic+0x106/0x300 lib/idr.c:125
 bpf_map_alloc_id+0x40/0xe0 kernel/bpf/syscall.c:356
 map_create+0xdc3/0x11c0 kernel/bpf/syscall.c:1398
 __sys_bpf+0x6c8/0x810 kernel/bpf/syscall.c:5661
 __do_sys_bpf kernel/bpf/syscall.c:5786 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5784 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5784
 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: 0033:0x7fe23117e719
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:00007fe231ee3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fe231335f80 RCX: 00007fe23117e719
RDX: 0000000000000048 RSI: 00000000200004c0 RDI: 0000000000000000
RBP: 00007fe2311f132e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fe231335f80 R15: 00007fff2658b528
 </TASK>


Tested on:

commit:         11066801 Merge tag 'linux_kselftest-fixes-6.12-rc6' of..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=143a5630580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a6b0d046ffd0e9c1
dashboard link: https://syzkaller.appspot.com/bug?extid=d2adb332fe371b0595e3
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=12ce3340580000