Hello, syzbot found the following issue on: HEAD commit: c3f38fa61af7 Linux 6.10-rc2 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=12e9d362980000 kernel config: https://syzkaller.appspot.com/x/.config?x=998c63c06e77f5e7 dashboard link: https://syzkaller.appspot.com/bug?extid=a4acbb99845d381e5e2f compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-c3f38fa6.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/af6a0b581dee/vmlinux-c3f38fa6.xz kernel image: https://storage.googleapis.com/syzbot-assets/47864da8bd74/bzImage-c3f38fa6.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a4acbb99845d381e5e2f@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc2-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.1/23904 is trying to acquire lock: ffff888040002018 (&n->list_lock){-.-.}-{2:2}, at: deactivate_slab+0x2b4/0x4a0 mm/slub.c:2948 but task is already holding lock: ffff88802792d9f8 (&trie->lock){-.-.}-{2:2}, at: trie_update_elem+0xc7/0xdb0 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}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 trie_delete_elem+0xb0/0x820 kernel/bpf/lpm_trie.c:462 0xffffffffa0001fd2 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+0x231/0x590 kernel/trace/bpf_trace.c:2444 trace_contention_end.constprop.0+0xea/0x170 include/trace/events/lock.h:122 __pv_queued_spin_lock_slowpath+0x28e/0xcc0 kernel/locking/qspinlock.c:557 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x210/0x2c0 kernel/locking/spinlock_debug.c:116 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0x42/0x60 kernel/locking/spinlock.c:162 get_partial_node.part.0+0x20/0x350 mm/slub.c:2675 get_partial_node mm/slub.c:2672 [inline] get_any_partial mm/slub.c:2759 [inline] get_partial mm/slub.c:2793 [inline] ___slab_alloc+0xd36/0x1870 mm/slub.c:3646 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3756 __slab_alloc_node mm/slub.c:3809 [inline] slab_alloc_node mm/slub.c:3988 [inline] kmem_cache_alloc_noprof+0x2ae/0x2f0 mm/slub.c:4007 getname_flags.part.0+0x50/0x4f0 fs/namei.c:139 getname_flags include/linux/audit.h:322 [inline] getname+0x8f/0xe0 fs/namei.c:218 do_sys_openat2+0x104/0x1e0 fs/open.c:1399 do_sys_open fs/open.c:1420 [inline] __do_sys_openat fs/open.c:1436 [inline] __se_sys_openat fs/open.c:1431 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1431 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 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 kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 deactivate_slab+0x2b4/0x4a0 mm/slub.c:2948 ___slab_alloc+0xc0b/0x1870 mm/slub.c:3591 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3756 __slab_alloc_node mm/slub.c:3809 [inline] slab_alloc_node mm/slub.c:3988 [inline] __do_kmalloc_node mm/slub.c:4120 [inline] __kmalloc_node_noprof+0x36c/0x450 mm/slub.c:4128 kmalloc_node_noprof include/linux/slab.h:681 [inline] bpf_map_kmalloc_node+0x98/0x4a0 kernel/bpf/syscall.c:422 lpm_trie_node_alloc kernel/bpf/lpm_trie.c:299 [inline] trie_update_elem+0x1ef/0xdb0 kernel/bpf/lpm_trie.c:342 bpf_map_update_value+0x2c1/0x6c0 kernel/bpf/syscall.c:203 generic_map_update_batch+0x454/0x5f0 kernel/bpf/syscall.c:1889 bpf_map_do_batch+0x615/0x6e0 kernel/bpf/syscall.c:5196 __sys_bpf+0x18cb/0x5830 kernel/bpf/syscall.c:5751 __do_sys_bpf kernel/bpf/syscall.c:5794 [inline] __se_sys_bpf kernel/bpf/syscall.c:5792 [inline] __ia32_sys_bpf+0x76/0xe0 kernel/bpf/syscall.c:5792 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e 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.1/23904: #0: ffffffff8dbb5160 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8dbb5160 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8dbb5160 (rcu_read_lock){....}-{1:2}, at: bpf_map_update_value+0x24b/0x6c0 kernel/bpf/syscall.c:202 #1: ffff88802792d9f8 (&trie->lock){-.-.}-{2:2}, at: trie_update_elem+0xc7/0xdb0 kernel/bpf/lpm_trie.c:333 stack backtrace: CPU: 3 PID: 23904 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/0x400 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 kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 deactivate_slab+0x2b4/0x4a0 mm/slub.c:2948 ___slab_alloc+0xc0b/0x1870 mm/slub.c:3591 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3756 __slab_alloc_node mm/slub.c:3809 [inline] slab_alloc_node mm/slub.c:3988 [inline] __do_kmalloc_node mm/slub.c:4120 [inline] __kmalloc_node_noprof+0x36c/0x450 mm/slub.c:4128 kmalloc_node_noprof include/linux/slab.h:681 [inline] bpf_map_kmalloc_node+0x98/0x4a0 kernel/bpf/syscall.c:422 lpm_trie_node_alloc kernel/bpf/lpm_trie.c:299 [inline] trie_update_elem+0x1ef/0xdb0 kernel/bpf/lpm_trie.c:342 bpf_map_update_value+0x2c1/0x6c0 kernel/bpf/syscall.c:203 generic_map_update_batch+0x454/0x5f0 kernel/bpf/syscall.c:1889 bpf_map_do_batch+0x615/0x6e0 kernel/bpf/syscall.c:5196 __sys_bpf+0x18cb/0x5830 kernel/bpf/syscall.c:5751 __do_sys_bpf kernel/bpf/syscall.c:5794 [inline] __se_sys_bpf kernel/bpf/syscall.c:5792 [inline] __ia32_sys_bpf+0x76/0xe0 kernel/bpf/syscall.c:5792 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf731f579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f5f115ac EFLAGS: 00000292 ORIG_RAX: 0000000000000165 RAX: ffffffffffffffda RBX: 000000000000001a RCX: 0000000020000100 RDX: 0000000000000038 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi --- 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@xxxxxxxxxxxxxxxx. 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
