syzbot


possible deadlock in get_partial_node

Status: upstream: reported on 2024/05/22 07:35
Subsystems: bpf
[Documentation on labels]
Reported-by: syzbot+9045c0a3d5a7f1b119f7@syzkaller.appspotmail.com
First crash: 27d, last: 3d12h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [bpf?] possible deadlock in get_partial_node 0 (1) 2024/05/22 07:35

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
6.10.0-rc3-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.1/8026 is trying to acquire lock:
ffff8880150403d8 (&n->list_lock){-.-.}-{2:2}, at: get_partial_node+0x36/0x280 mm/slub.c:2676

but task is already holding lock:
ffff888011f561f8 (&trie->lock){....}-{2:2}, at: trie_update_elem+0xc8/0xc00 kernel/bpf/lpm_trie.c:333

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&trie->lock){....}-{2:2}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
       trie_delete_elem+0x96/0x6a0 kernel/bpf/lpm_trie.c:462
       0xffffffffa0001fce
       bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
       __bpf_prog_run include/linux/filter.h:691 [inline]
       bpf_prog_run include/linux/filter.h:698 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:2403 [inline]
       bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2444
       trace_contention_end+0x114/0x140 include/trace/events/lock.h:122
       __pv_queued_spin_lock_slowpath+0xb81/0xdc0 kernel/locking/qspinlock.c:557
       pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline]
       queued_spin_lock_slowpath+0x42/0x50 arch/x86/include/asm/qspinlock.h:51
       queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
       do_raw_spin_lock+0x272/0x370 kernel/locking/spinlock_debug.c:116
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
       _raw_spin_lock_irqsave+0xe1/0x120 kernel/locking/spinlock.c:162
       __slab_free+0xec/0x3d0 mm/slub.c:4283
       qlink_free mm/kasan/quarantine.c:163 [inline]
       qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179
       kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
       __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322
       kasan_slab_alloc include/linux/kasan.h:201 [inline]
       slab_post_alloc_hook mm/slub.c:3941 [inline]
       slab_alloc_node mm/slub.c:4001 [inline]
       kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4008
       getname_flags+0xbd/0x4f0 fs/namei.c:139
       getname fs/namei.c:218 [inline]
       __do_sys_mkdirat fs/namei.c:4169 [inline]
       __se_sys_mkdirat fs/namei.c:4167 [inline]
       __x64_sys_mkdirat+0x7c/0xa0 fs/namei.c:4167
       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

-> #0 (&n->list_lock){-.-.}-{2:2}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869
       __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
       get_partial_node+0x36/0x280 mm/slub.c:2676
       get_partial mm/slub.c:2790 [inline]
       ___slab_alloc+0xc17/0x14b0 mm/slub.c:3647
       __slab_alloc+0x58/0xa0 mm/slub.c:3757
       __slab_alloc_node mm/slub.c:3810 [inline]
       slab_alloc_node mm/slub.c:3989 [inline]
       kmalloc_trace_noprof+0x1d5/0x2c0 mm/slub.c:4148
       kmalloc_noprof include/linux/slab.h:660 [inline]
       add_stack_record_to_list mm/page_owner.c:172 [inline]
       inc_stack_record_count mm/page_owner.c:214 [inline]
       __set_page_owner+0x55f/0x800 mm/page_owner.c:329
       set_page_owner include/linux/page_owner.h:32 [inline]
       post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1468
       prep_new_page mm/page_alloc.c:1476 [inline]
       get_page_from_freelist+0x2e43/0x2f00 mm/page_alloc.c:3420
       __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4678
       __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
       alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
       __kmalloc_large_node+0x8b/0x1d0 mm/slub.c:4067
       __do_kmalloc_node mm/slub.c:4110 [inline]
       __kmalloc_node_noprof+0x2d2/0x440 mm/slub.c:4129
       kmalloc_node_noprof include/linux/slab.h:681 [inline]
       bpf_map_kmalloc_node+0xd3/0x1c0 kernel/bpf/syscall.c:422
       lpm_trie_node_alloc kernel/bpf/lpm_trie.c:299 [inline]
       trie_update_elem+0x1cd/0xc00 kernel/bpf/lpm_trie.c:342
       bpf_map_update_value+0x4d3/0x540 kernel/bpf/syscall.c:203
       map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1654
       __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5676
       __do_sys_bpf kernel/bpf/syscall.c:5795 [inline]
       __se_sys_bpf kernel/bpf/syscall.c:5793 [inline]
       __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5793
       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

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&trie->lock);
                               lock(&n->list_lock);
                               lock(&trie->lock);
  lock(&n->list_lock);

 *** DEADLOCK ***

2 locks held by syz-executor.1/8026:
 #0: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
 #0: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
 #0: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: bpf_map_update_value+0x3c4/0x540 kernel/bpf/syscall.c:202
 #1: ffff888011f561f8 (&trie->lock){....}-{2:2}, at: trie_update_elem+0xc8/0xc00 kernel/bpf/lpm_trie.c:333

stack backtrace:
CPU: 1 PID: 8026 Comm: syz-executor.1 Not tainted 6.10.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869
 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
 get_partial_node+0x36/0x280 mm/slub.c:2676
 get_partial mm/slub.c:2790 [inline]
 ___slab_alloc+0xc17/0x14b0 mm/slub.c:3647
 __slab_alloc+0x58/0xa0 mm/slub.c:3757
 __slab_alloc_node mm/slub.c:3810 [inline]
 slab_alloc_node mm/slub.c:3989 [inline]
 kmalloc_trace_noprof+0x1d5/0x2c0 mm/slub.c:4148
 kmalloc_noprof include/linux/slab.h:660 [inline]
 add_stack_record_to_list mm/page_owner.c:172 [inline]
 inc_stack_record_count mm/page_owner.c:214 [inline]
 __set_page_owner+0x55f/0x800 mm/page_owner.c:329
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1468
 prep_new_page mm/page_alloc.c:1476 [inline]
 get_page_from_freelist+0x2e43/0x2f00 mm/page_alloc.c:3420
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4678
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 __kmalloc_large_node+0x8b/0x1d0 mm/slub.c:4067
 __do_kmalloc_node mm/slub.c:4110 [inline]
 __kmalloc_node_noprof+0x2d2/0x440 mm/slub.c:4129
 kmalloc_node_noprof include/linux/slab.h:681 [inline]
 bpf_map_kmalloc_node+0xd3/0x1c0 kernel/bpf/syscall.c:422
 lpm_trie_node_alloc kernel/bpf/lpm_trie.c:299 [inline]
 trie_update_elem+0x1cd/0xc00 kernel/bpf/lpm_trie.c:342
 bpf_map_update_value+0x4d3/0x540 kernel/bpf/syscall.c:203
 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1654
 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5676
 __do_sys_bpf kernel/bpf/syscall.c:5795 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5793 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5793
 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: 0033:0x7f1b7567cea9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1b763a00c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f1b757b4120 RCX: 00007f1b7567cea9
RDX: 0000000000000020 RSI: 0000000020000380 RDI: 0000000000000002
RBP: 00007f1b756ebff4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f1b757b4120 R15: 00007ffc6c620bd8
 </TASK>

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/11 16:14 upstream 83a7eefedc9b c7d7d815 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in get_partial_node
2024/06/03 13:02 upstream c3f38fa61af7 0aba2352 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root possible deadlock in get_partial_node
2024/06/02 02:48 upstream cc8ed4d0a848 3113787f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in get_partial_node
2024/05/29 21:34 upstream 4a4be1ad3a6e 34889ee3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in get_partial_node
2024/05/29 20:20 upstream 4a4be1ad3a6e c2e07261 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 possible deadlock in get_partial_node
2024/05/31 08:02 net 068648aab72c 34889ee3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce possible deadlock in get_partial_node
2024/05/18 15:34 net-next 4b377b4868ef c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in get_partial_node
2024/05/18 09:31 net-next 4b377b4868ef c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in get_partial_node
2024/05/18 07:31 net-next 4b377b4868ef c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in get_partial_node
* Struck through repros no longer work on HEAD.