[<prev] [next>] [day] [month] [year] [list]
Message-ID: <67126fa4.050a0220.10f4f4.0015.GAE@google.com>
Date: Fri, 18 Oct 2024 07:24:36 -0700
From: syzbot <syzbot+b12149f7ab5a8751740f@...kaller.appspotmail.com>
To: andrii@...nel.org, ast@...nel.org, bpf@...r.kernel.org,
daniel@...earbox.net, eddyz87@...il.com, haoluo@...gle.com,
john.fastabend@...il.com, jolsa@...nel.org, kpsingh@...nel.org,
linux-kernel@...r.kernel.org, martin.lau@...ux.dev, netdev@...r.kernel.org,
sdf@...ichev.me, song@...nel.org, syzkaller-bugs@...glegroups.com,
yonghong.song@...ux.dev
Subject: [syzbot] [bpf?] possible deadlock in debug_check_no_obj_freed
Hello,
syzbot found the following issue on:
HEAD commit: 989a29cfed9b libbpf: Fix possible compiler warnings in has..
git tree: bpf-next
console output: https://syzkaller.appspot.com/x/log.txt?x=116c5440580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f95955e3f7b5790c
dashboard link: https://syzkaller.appspot.com/bug?extid=b12149f7ab5a8751740f
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/628a969b8618/disk-989a29cf.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/20c58ef873dc/vmlinux-989a29cf.xz
kernel image: https://storage.googleapis.com/syzbot-assets/cda8b348a2ce/bzImage-989a29cf.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b12149f7ab5a8751740f@...kaller.appspotmail.com
======================================================
WARNING: possible circular locking dependency detected
6.12.0-rc1-syzkaller-00176-g989a29cfed9b #0 Not tainted
------------------------------------------------------
syz.1.55/5474 is trying to acquire lock:
ffffffff9a614a58 (&obj_hash[i].lock){-.-.}-{2:2}, at: __debug_check_no_obj_freed lib/debugobjects.c:978 [inline]
ffffffff9a614a58 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_check_no_obj_freed+0x234/0x580 lib/debugobjects.c:1019
but task is already holding lock:
ffff88805c781a00 (&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:5825
__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
0xffffffffa000492e
bpf_dispatcher_nop_func include/linux/bpf.h:1257 [inline]
__bpf_prog_run include/linux/filter.h:701 [inline]
bpf_prog_run include/linux/filter.h:708 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2318 [inline]
bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2359
trace_contention_end+0x114/0x140 include/trace/events/lock.h:122
__pv_queued_spin_lock_slowpath+0xb7e/0xdb0 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
debug_object_active_state+0x15d/0x360 lib/debugobjects.c:936
debug_rcu_head_unqueue kernel/rcu/rcu.h:233 [inline]
rcu_do_batch kernel/rcu/tree.c:2559 [inline]
rcu_core+0xa21/0x17a0 kernel/rcu/tree.c:2823
handle_softirqs+0x2c5/0x980 kernel/softirq.c:554
run_ksoftirqd+0xca/0x130 kernel/softirq.c:927
smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
-> #0 (&obj_hash[i].lock){-.-.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
__lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
__debug_check_no_obj_freed lib/debugobjects.c:978 [inline]
debug_check_no_obj_freed+0x234/0x580 lib/debugobjects.c:1019
free_pages_prepare mm/page_alloc.c:1115 [inline]
free_unref_page+0x41b/0xf20 mm/page_alloc.c:2638
stack_depot_save_flags+0x6f6/0x830 lib/stackdepot.c:666
kasan_save_stack mm/kasan/common.c:48 [inline]
kasan_save_track+0x51/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:257 [inline]
__do_kmalloc_node mm/slub.c:4265 [inline]
__kmalloc_node_noprof+0x22a/0x440 mm/slub.c:4271
kmalloc_array_node_noprof include/linux/slab.h:995 [inline]
alloc_slab_obj_exts mm/slub.c:1969 [inline]
account_slab mm/slub.c:2542 [inline]
allocate_slab+0xb6/0x2f0 mm/slub.c:2597
new_slab mm/slub.c:2632 [inline]
___slab_alloc+0xcd1/0x14b0 mm/slub.c:3819
__slab_alloc+0x58/0xa0 mm/slub.c:3909
__slab_alloc_node mm/slub.c:3962 [inline]
slab_alloc_node mm/slub.c:4123 [inline]
__do_kmalloc_node mm/slub.c:4264 [inline]
__kmalloc_node_noprof+0x286/0x440 mm/slub.c:4271
kmalloc_node_noprof include/linux/slab.h:905 [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+0x51a/0x6f0 kernel/bpf/syscall.c:1626
__sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5622
__do_sys_bpf kernel/bpf/syscall.c:5741 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5739 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5739
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(&obj_hash[i].lock);
lock(&trie->lock);
lock(&obj_hash[i].lock);
*** DEADLOCK ***
2 locks held by syz.1.55/5474:
#0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: bpf_map_update_value+0x3c4/0x540 kernel/bpf/syscall.c:202
#1: ffff88805c781a00 (&trie->lock){-.-.}-{2:2}, at: trie_update_elem+0xc8/0xc00 kernel/bpf/lpm_trie.c:333
stack backtrace:
CPU: 1 UID: 0 PID: 5474 Comm: syz.1.55 Not tainted 6.12.0-rc1-syzkaller-00176-g989a29cfed9b #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_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074
check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206
check_prev_add kernel/locking/lockdep.c:3161 [inline]
check_prevs_add kernel/locking/lockdep.c:3280 [inline]
validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904
__lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162
__debug_check_no_obj_freed lib/debugobjects.c:978 [inline]
debug_check_no_obj_freed+0x234/0x580 lib/debugobjects.c:1019
free_pages_prepare mm/page_alloc.c:1115 [inline]
free_unref_page+0x41b/0xf20 mm/page_alloc.c:2638
stack_depot_save_flags+0x6f6/0x830 lib/stackdepot.c:666
kasan_save_stack mm/kasan/common.c:48 [inline]
kasan_save_track+0x51/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:257 [inline]
__do_kmalloc_node mm/slub.c:4265 [inline]
__kmalloc_node_noprof+0x22a/0x440 mm/slub.c:4271
kmalloc_array_node_noprof include/linux/slab.h:995 [inline]
alloc_slab_obj_exts mm/slub.c:1969 [inline]
account_slab mm/slub.c:2542 [inline]
allocate_slab+0xb6/0x2f0 mm/slub.c:2597
new_slab mm/slub.c:2632 [inline]
___slab_alloc+0xcd1/0x14b0 mm/slub.c:3819
__slab_alloc+0x58/0xa0 mm/slub.c:3909
__slab_alloc_node mm/slub.c:3962 [inline]
slab_alloc_node mm/slub.c:4123 [inline]
__do_kmalloc_node mm/slub.c:4264 [inline]
__kmalloc_node_noprof+0x286/0x440 mm/slub.c:4271
kmalloc_node_noprof include/linux/slab.h:905 [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+0x51a/0x6f0 kernel/bpf/syscall.c:1626
__sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5622
__do_sys_bpf kernel/bpf/syscall.c:5741 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5739 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5739
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: 0033:0x7f93def7dff9
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:00007f93dfe48038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f93df135f80 RCX: 00007f93def7dff9
RDX: 0000000000000020 RSI: 00000000200004c0 RDI: 0000000000000002
RBP: 00007f93deff0296 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f93df135f80 R15: 00007fff24bc8458
</TASK>
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@...glegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
Powered by blists - more mailing lists