============================================ WARNING: possible recursive locking detected 6.1.92-syzkaller #0 Not tainted -------------------------------------------- syz-executor.3/4721 is trying to acquire lock: ffff8880b9835e90 (lock#10){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ffff8880b9835e90 (lock#10){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x84/0x670 mm/mmap_lock.c:237 but task is already holding lock: ffff8880b9835e90 (lock#10){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ffff8880b9835e90 (lock#10){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x84/0x670 mm/mmap_lock.c:237 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(lock#10); lock(lock#10); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by syz-executor.3/4721: #0: ffff8880228e9f58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff8880228e9f58 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5304 [inline] #0: ffff8880228e9f58 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2e0 mm/memory.c:5366 #1: ffff8880b9835e90 (lock#10){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] #1: ffff8880b9835e90 (lock#10){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x84/0x670 mm/mmap_lock.c:237 #2: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #2: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #2: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: get_memcg_path_buf mm/mmap_lock.c:139 [inline] #2: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: get_mm_memcg_path+0xb1/0x600 mm/mmap_lock.c:209 #3: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #3: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #3: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2272 [inline] #3: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x16a/0x470 kernel/trace/bpf_trace.c:2314 #4: ffff8880228e9f58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #4: ffff8880228e9f58 (&mm->mmap_lock){++++}-{3:3}, at: stack_map_get_build_id_offset+0x232/0x9c0 kernel/bpf/stackmap.c:144 stack backtrace: CPU: 0 PID: 4721 Comm: syz-executor.3 Not tainted 6.1.92-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2983 [inline] check_deadlock kernel/locking/lockdep.c:3026 [inline] validate_chain+0x4711/0x5950 kernel/locking/lockdep.c:3812 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] __mmap_lock_do_trace_acquire_returned+0x9d/0x670 mm/mmap_lock.c:237 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:137 [inline] stack_map_get_build_id_offset+0x99e/0x9c0 kernel/bpf/stackmap.c:144 __bpf_get_stack+0x495/0x570 kernel/bpf/stackmap.c:452 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1877 [inline] bpf_get_stack_raw_tp+0x1b2/0x220 kernel/trace/bpf_trace.c:1867 bpf_prog_e6cf5f9c69743609+0x3a/0x3e bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline] __bpf_prog_run include/linux/filter.h:603 [inline] bpf_prog_run include/linux/filter.h:610 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2273 [inline] bpf_trace_run4+0x253/0x470 kernel/trace/bpf_trace.c:2314 trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:52 [inline] __mmap_lock_do_trace_acquire_returned+0x5e3/0x670 mm/mmap_lock.c:237 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:137 [inline] get_mmap_lock_carefully mm/memory.c:5304 [inline] lock_mm_and_find_vma+0x219/0x2e0 mm/memory.c:5366 do_user_addr_fault arch/x86/mm/fault.c:1343 [inline] handle_page_fault arch/x86/mm/fault.c:1462 [inline] exc_page_fault+0x169/0x660 arch/x86/mm/fault.c:1518 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0010:do_strncpy_from_user lib/strncpy_from_user.c:41 [inline] RIP: 0010:strncpy_from_user+0x159/0x360 lib/strncpy_from_user.c:139 Code: 27 fd 48 83 fd 07 0f 86 af 00 00 00 4c 89 64 24 08 4c 89 7c 24 10 48 c7 44 24 18 f8 ff ff ff 45 31 ed 4d 89 f4 48 8b 44 24 08 <4e> 8b 3c 28 48 b8 ff fe fe fe fe fe fe fe 49 8d 1c 07 4d 89 fe 49 RSP: 0018:ffffc9000324fb48 EFLAGS: 00050246 RAX: 0000000000000000 RBX: 00007fffffffef81 RCX: ffff8880222c3b80 RDX: ffffc90005602000 RSI: 000000000000007f RDI: 0000000000000007 RBP: 000000000000007f R08: ffffffff84630b11 R09: ffffffff81eeb403 R10: 0000000000000003 R11: ffff8880222c3b80 R12: ffffc9000324fc70 R13: 0000000000000000 R14: ffffc9000324fc70 R15: 000000000000007f strncpy_from_bpfptr include/linux/bpfptr.h:85 [inline] bpf_prog_load+0x188/0x1bb0 kernel/bpf/syscall.c:2515 __sys_bpf+0x382/0x6c0 kernel/bpf/syscall.c:5005 __do_sys_bpf kernel/bpf/syscall.c:5109 [inline] __se_sys_bpf kernel/bpf/syscall.c:5107 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5107 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f848907cee9 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:00007f8489eb30c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f84891b3fa0 RCX: 00007f848907cee9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00007f84890c947f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f84891b3fa0 R15: 00007ffeba03be08 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: fd std 1: 48 83 fd 07 cmp $0x7,%rbp 5: 0f 86 af 00 00 00 jbe 0xba b: 4c 89 64 24 08 mov %r12,0x8(%rsp) 10: 4c 89 7c 24 10 mov %r15,0x10(%rsp) 15: 48 c7 44 24 18 f8 ff movq $0xfffffffffffffff8,0x18(%rsp) 1c: ff ff 1e: 45 31 ed xor %r13d,%r13d 21: 4d 89 f4 mov %r14,%r12 24: 48 8b 44 24 08 mov 0x8(%rsp),%rax * 29: 4e 8b 3c 28 mov (%rax,%r13,1),%r15 <-- trapping instruction 2d: 48 b8 ff fe fe fe fe movabs $0xfefefefefefefeff,%rax 34: fe fe fe 37: 49 8d 1c 07 lea (%r15,%rax,1),%rbx 3b: 4d 89 fe mov %r15,%r14 3e: 49 rex.WB