syzbot


possible deadlock in get_page_from_freelist

Status: upstream: reported on 2024/04/15 02:28
Subsystems: bpf
[Documentation on labels]
Reported-by: syzbot+a7f061d2d16154538c58@syzkaller.appspotmail.com
First crash: 40d, last: 2d22h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [bpf?] possible deadlock in get_page_from_freelist 5 (6) 2024/05/20 11:44
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 possible deadlock in get_page_from_freelist 1 47d 47d 0/3 upstream: reported on 2024/04/04 02:53

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
6.9.0-rc7-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.1/5201 is trying to acquire lock:
ffff88813fffad58 (&zone->lock){-.-.}-{2:2}, at: rmqueue_buddy mm/page_alloc.c:2730 [inline]
ffff88813fffad58 (&zone->lock){-.-.}-{2:2}, at: rmqueue mm/page_alloc.c:2911 [inline]
ffff88813fffad58 (&zone->lock){-.-.}-{2:2}, at: get_page_from_freelist+0xb08/0x35b0 mm/page_alloc.c:3314

but task is already holding lock:
ffff88807cba71f8 (&trie->lock){-.-.}-{2:2}, at: trie_update_elem+0xcb/0xc10 kernel/bpf/lpm_trie.c:324

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:451
       0xffffffffa0002061
       bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
       __bpf_prog_run include/linux/filter.h:657 [inline]
       bpf_prog_run include/linux/filter.h:664 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
       bpf_trace_run2+0x204/0x420 kernel/trace/bpf_trace.c:2420
       trace_contention_end+0x114/0x140 include/trace/events/lock.h:122
       __pv_queued_spin_lock_slowpath+0x939/0xc60 kernel/locking/qspinlock.c:560
       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
       rmqueue_bulk mm/page_alloc.c:2131 [inline]
       __rmqueue_pcplist+0x520/0x2620 mm/page_alloc.c:2826
       rmqueue_pcplist mm/page_alloc.c:2868 [inline]
       rmqueue mm/page_alloc.c:2905 [inline]
       get_page_from_freelist+0x856/0x35b0 mm/page_alloc.c:3314
       __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575
       alloc_pages_mpol+0x3e8/0x680 mm/mempolicy.c:2264
       alloc_pages mm/mempolicy.c:2335 [inline]
       folio_alloc+0x128/0x180 mm/mempolicy.c:2342
       filemap_alloc_folio+0xdf/0x500 mm/filemap.c:984
       __filemap_get_folio+0x41a/0xbb0 mm/filemap.c:1926
       grow_dev_folio fs/buffer.c:1042 [inline]
       grow_buffers fs/buffer.c:1108 [inline]
       __getblk_slow fs/buffer.c:1134 [inline]
       bdev_getblk+0x234/0x610 fs/buffer.c:1429
       __getblk include/linux/buffer_head.h:355 [inline]
       jbd2_journal_get_descriptor_buffer+0x1e6/0x4e0 fs/jbd2/journal.c:1010
       jbd2_journal_commit_transaction+0x1724/0x6760 fs/jbd2/commit.c:611
       kjournald2+0x463/0x850 fs/jbd2/journal.c:201
       kthread+0x2f0/0x390 kernel/kthread.c:388
       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 (&zone->lock){-.-.}-{2:2}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain+0x18cb/0x58e0 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
       rmqueue_buddy mm/page_alloc.c:2730 [inline]
       rmqueue mm/page_alloc.c:2911 [inline]
       get_page_from_freelist+0xb08/0x35b0 mm/page_alloc.c:3314
       __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575
       __alloc_pages_node include/linux/gfp.h:238 [inline]
       alloc_pages_node include/linux/gfp.h:261 [inline]
       __kmalloc_large_node+0x91/0x1f0 mm/slub.c:3911
       __do_kmalloc_node mm/slub.c:3954 [inline]
       __kmalloc_node+0x33e/0x4e0 mm/slub.c:3973
       kmalloc_node include/linux/slab.h:648 [inline]
       bpf_map_kmalloc_node+0xd3/0x1c0 kernel/bpf/syscall.c:422
       lpm_trie_node_alloc kernel/bpf/lpm_trie.c:291 [inline]
       trie_update_elem+0x1d3/0xc10 kernel/bpf/lpm_trie.c:333
       bpf_map_update_value+0x4d3/0x540 kernel/bpf/syscall.c:203
       map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641
       __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5648
       __do_sys_bpf kernel/bpf/syscall.c:5767 [inline]
       __se_sys_bpf kernel/bpf/syscall.c:5765 [inline]
       __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5765
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf5/0x240 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(&zone->lock);
                               lock(&trie->lock);
  lock(&zone->lock);

 *** DEADLOCK ***

2 locks held by syz-executor.1/5201:
 #0: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
 #0: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
 #0: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: bpf_map_update_value+0x3c4/0x540 kernel/bpf/syscall.c:202
 #1: ffff88807cba71f8 (&trie->lock){-.-.}-{2:2}, at: trie_update_elem+0xcb/0xc10 kernel/bpf/lpm_trie.c:324

stack backtrace:
CPU: 0 PID: 5201 Comm: syz-executor.1 Not tainted 6.9.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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+0x18cb/0x58e0 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
 rmqueue_buddy mm/page_alloc.c:2730 [inline]
 rmqueue mm/page_alloc.c:2911 [inline]
 get_page_from_freelist+0xb08/0x35b0 mm/page_alloc.c:3314
 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 __kmalloc_large_node+0x91/0x1f0 mm/slub.c:3911
 __do_kmalloc_node mm/slub.c:3954 [inline]
 __kmalloc_node+0x33e/0x4e0 mm/slub.c:3973
 kmalloc_node include/linux/slab.h:648 [inline]
 bpf_map_kmalloc_node+0xd3/0x1c0 kernel/bpf/syscall.c:422
 lpm_trie_node_alloc kernel/bpf/lpm_trie.c:291 [inline]
 trie_update_elem+0x1d3/0xc10 kernel/bpf/lpm_trie.c:333
 bpf_map_update_value+0x4d3/0x540 kernel/bpf/syscall.c:203
 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641
 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5648
 __do_sys_bpf kernel/bpf/syscall.c:5767 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5765 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5765
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc8c487dca9
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:00007fc8c56a60c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fc8c49abf80 RCX: 00007fc8c487dca9
RDX: 0000000000000020 RSI: 0000000020000080 RDI: 0000000000000002
RBP: 00007fc8c48c947e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fc8c49abf80 R15: 00007fff9aa816b8
 </TASK>

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/06 18:37 upstream dd5a440a31fa c035c6de .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root possible deadlock in get_page_from_freelist
2024/04/15 10:18 upstream 0bbac3facb5d 459f4b00 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream possible deadlock in get_page_from_freelist
2024/04/14 18:24 upstream 7efd0a74039f c8349e48 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream possible deadlock in get_page_from_freelist
2024/05/18 20:12 net-next 4b377b4868ef c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in get_page_from_freelist
2024/05/18 14:13 net-next 4b377b4868ef c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in get_page_from_freelist
2024/04/11 02:21 linux-next 6ebf211bb11d 56086b24 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root possible deadlock in get_page_from_freelist
* Struck through repros no longer work on HEAD.