====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc4-syzkaller-00308-ga79a588fc176 #0 Not tainted ------------------------------------------------------ syz.3.624/10831 is trying to acquire lock: ffff888050d2bf60 (&ocfs2_file_ip_alloc_sem_key){++++}-{4:4}, at: ocfs2_page_mkwrite+0x2ff/0xc40 fs/ocfs2/mmap.c:142 but task is already holding lock: ffff88803462c520 (sb_pagefaults#6){.+.+}-{0:0}, at: do_page_mkwrite+0x14d/0x310 mm/memory.c:3378 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (sb_pagefaults#6){.+.+}-{0:0}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs.h:1795 [inline] sb_start_pagefault include/linux/fs.h:1960 [inline] ocfs2_page_mkwrite+0x1da/0xc40 fs/ocfs2/mmap.c:122 do_page_mkwrite+0x14d/0x310 mm/memory.c:3378 do_shared_fault mm/memory.c:5666 [inline] do_fault mm/memory.c:5728 [inline] do_pte_missing mm/memory.c:4251 [inline] handle_pte_fault mm/memory.c:6069 [inline] __handle_mm_fault+0x1a60/0x5620 mm/memory.c:6212 handle_mm_fault+0x2d5/0x7f0 mm/memory.c:6381 do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1387 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #1 (&mm->mmap_lock){++++}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __might_fault+0xcc/0x130 mm/memory.c:6971 _inline_copy_to_user include/linux/uaccess.h:192 [inline] _copy_to_user+0x2c/0xb0 lib/usercopy.c:26 copy_to_user include/linux/uaccess.h:225 [inline] fiemap_fill_next_extent+0x1c0/0x390 fs/ioctl.c:145 ocfs2_fiemap_inline fs/ocfs2/extent_map.c:735 [inline] ocfs2_fiemap+0x9dc/0xc90 fs/ocfs2/extent_map.c:772 ioctl_fiemap fs/ioctl.c:220 [inline] do_vfs_ioctl+0x16d0/0x1990 fs/ioctl.c:841 __do_sys_ioctl fs/ioctl.c:905 [inline] __se_sys_ioctl+0x82/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&ocfs2_file_ip_alloc_sem_key){++++}-{4:4}: check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x2ff/0xc40 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x14d/0x310 mm/memory.c:3378 do_shared_fault mm/memory.c:5666 [inline] do_fault mm/memory.c:5728 [inline] do_pte_missing mm/memory.c:4251 [inline] handle_pte_fault mm/memory.c:6069 [inline] __handle_mm_fault+0x1a60/0x5620 mm/memory.c:6212 handle_mm_fault+0x2d5/0x7f0 mm/memory.c:6381 do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1387 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 user_access_begin arch/x86/include/asm/uaccess.h:-1 [inline] filldir64+0x2a3/0x690 fs/readdir.c:373 dir_emit_dot include/linux/fs.h:3925 [inline] dir_emit_dots include/linux/fs.h:3936 [inline] offset_readdir+0x1e6/0x560 fs/libfs.c:572 iterate_dir+0x5ac/0x770 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:410 [inline] __se_sys_getdents64+0xe4/0x260 fs/readdir.c:396 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: &ocfs2_file_ip_alloc_sem_key --> &mm->mmap_lock --> sb_pagefaults#6 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(sb_pagefaults#6); lock(&mm->mmap_lock); lock(sb_pagefaults#6); lock(&ocfs2_file_ip_alloc_sem_key); *** DEADLOCK *** 4 locks held by syz.3.624/10831: #0: ffff88802fb84478 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1217 #1: ffff888024c8d7b0 (&type->i_mutex_dir_key#5){++++}-{4:4}, at: iterate_dir+0x49f/0x770 fs/readdir.c:101 #2: ffff888034836ae0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:431 [inline] #2: ffff888034836ae0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:188 [inline] #2: ffff888034836ae0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x32/0x300 mm/mmap_lock.c:248 #3: ffff88803462c520 (sb_pagefaults#6){.+.+}-{0:0}, at: do_page_mkwrite+0x14d/0x310 mm/memory.c:3378 stack backtrace: CPU: 0 UID: 0 PID: 10831 Comm: syz.3.624 Not tainted 6.16.0-rc4-syzkaller-00308-ga79a588fc176 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2046 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x2ff/0xc40 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x14d/0x310 mm/memory.c:3378 do_shared_fault mm/memory.c:5666 [inline] do_fault mm/memory.c:5728 [inline] do_pte_missing mm/memory.c:4251 [inline] handle_pte_fault mm/memory.c:6069 [inline] __handle_mm_fault+0x1a60/0x5620 mm/memory.c:6212 handle_mm_fault+0x2d5/0x7f0 mm/memory.c:6381 do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1387 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:filldir64+0x2a3/0x690 fs/readdir.c:377 Code: 88 ff 4c 89 ff 4c 89 e6 e8 ea 9a 88 ff 4d 39 e7 0f 82 5b 02 00 00 49 39 ef 0f 87 52 02 00 00 0f 01 cb 0f ae e8 48 8b 44 24 50 <49> 89 44 24 08 48 8b 4c 24 08 48 8b 44 24 58 48 89 01 48 8b 04 24 RSP: 0018:ffffc90004007c88 EFLAGS: 00050283 RAX: 0000000000000000 RBX: ffffc90004007e38 RCX: ffff88801eb19e00 RDX: 0000000000000002 RSI: 0000200000000f80 RDI: 0000200000000f98 RBP: 00007ffffffff000 R08: 0000000000000381 R09: 0000000000000004 R10: 000000007fffffff R11: ffffffff8237c270 R12: 0000200000000f80 R13: ffffffff8b998be0 R14: 0000000000000001 R15: 0000200000000f98 dir_emit_dot include/linux/fs.h:3925 [inline] dir_emit_dots include/linux/fs.h:3936 [inline] offset_readdir+0x1e6/0x560 fs/libfs.c:572 iterate_dir+0x5ac/0x770 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:410 [inline] __se_sys_getdents64+0xe4/0x260 fs/readdir.c:396 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f97c6b8e929 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:00007f97c79a0038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007f97c6db5fa0 RCX: 00007f97c6b8e929 RDX: 0000000000001000 RSI: 0000200000000f80 RDI: 0000000000000003 RBP: 00007f97c6c10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f97c6db5fa0 R15: 00007fff79551ba8 ---------------- Code disassembly (best guess): 0: 88 ff mov %bh,%bh 2: 4c 89 ff mov %r15,%rdi 5: 4c 89 e6 mov %r12,%rsi 8: e8 ea 9a 88 ff call 0xff889af7 d: 4d 39 e7 cmp %r12,%r15 10: 0f 82 5b 02 00 00 jb 0x271 16: 49 39 ef cmp %rbp,%r15 19: 0f 87 52 02 00 00 ja 0x271 1f: 0f 01 cb stac 22: 0f ae e8 lfence 25: 48 8b 44 24 50 mov 0x50(%rsp),%rax * 2a: 49 89 44 24 08 mov %rax,0x8(%r12) <-- trapping instruction 2f: 48 8b 4c 24 08 mov 0x8(%rsp),%rcx 34: 48 8b 44 24 58 mov 0x58(%rsp),%rax 39: 48 89 01 mov %rax,(%rcx) 3c: 48 8b 04 24 mov (%rsp),%rax