====================================================== WARNING: possible circular locking dependency detected 6.12.0-rc5-next-20241031-syzkaller #0 Not tainted ------------------------------------------------------ syz.7.491/8125 is trying to acquire lock: ffff88805fcbb120 (&ocfs2_file_ip_alloc_sem_key){++++}-{4:4}, at: ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142 but task is already holding lock: ffff88807ef6a518 (sb_pagefaults#6){.+.+}-{0:0}, at: do_page_mkwrite+0x198/0x480 mm/memory.c:3176 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (sb_pagefaults#6){.+.+}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1724 [inline] sb_start_pagefault include/linux/fs.h:1889 [inline] ocfs2_page_mkwrite+0x222/0xed0 fs/ocfs2/mmap.c:122 do_page_mkwrite+0x198/0x480 mm/memory.c:3176 do_shared_fault mm/memory.c:5398 [inline] do_fault mm/memory.c:5460 [inline] do_pte_missing mm/memory.c:3979 [inline] handle_pte_fault+0x122e/0x66b0 mm/memory.c:5801 __handle_mm_fault mm/memory.c:5944 [inline] handle_mm_fault+0x1106/0x1bb0 mm/memory.c:6112 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #1 (&mm->mmap_lock){++++}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __might_fault+0xc6/0x120 mm/memory.c:6751 _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+0x235/0x410 fs/ioctl.c:145 ocfs2_fiemap+0x9f1/0xf80 fs/ocfs2/extent_map.c:796 ioctl_fiemap fs/ioctl.c:220 [inline] do_vfs_ioctl+0x1bf8/0x2e40 fs/ioctl.c:841 __do_sys_ioctl fs/ioctl.c:905 [inline] __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893 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 -> #0 (&ocfs2_file_ip_alloc_sem_key){++++}-{4:4}: 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+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 down_write+0x99/0x220 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x198/0x480 mm/memory.c:3176 do_shared_fault mm/memory.c:5398 [inline] do_fault mm/memory.c:5460 [inline] do_pte_missing mm/memory.c:3979 [inline] handle_pte_fault+0x122e/0x66b0 mm/memory.c:5801 __handle_mm_fault mm/memory.c:5944 [inline] handle_mm_fault+0x1106/0x1bb0 mm/memory.c:6112 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 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 *** 2 locks held by syz.7.491/8125: #0: ffff888034b5e5e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:208 [inline] #0: ffff888034b5e5e0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/memory.c:6149 [inline] #0: ffff888034b5e5e0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:6209 #1: ffff88807ef6a518 (sb_pagefaults#6){.+.+}-{0:0}, at: do_page_mkwrite+0x198/0x480 mm/memory.c:3176 stack backtrace: CPU: 1 UID: 0 PID: 8125 Comm: syz.7.491 Not tainted 6.12.0-rc5-next-20241031-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __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+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 down_write+0x99/0x220 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x198/0x480 mm/memory.c:3176 do_shared_fault mm/memory.c:5398 [inline] do_fault mm/memory.c:5460 [inline] do_pte_missing mm/memory.c:3979 [inline] handle_pte_fault+0x122e/0x66b0 mm/memory.c:5801 __handle_mm_fault mm/memory.c:5944 [inline] handle_mm_fault+0x1106/0x1bb0 mm/memory.c:6112 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f4ae55461ab Code: fa 10 73 2d 83 fa 08 73 46 83 fa 04 73 16 83 fa 01 7c 10 8a 0e 74 0a 0f b7 74 16 fe 66 89 74 17 fe 88 0f c3 8b 4c 16 fc 8b 36 <89> 4c 17 fc 89 37 c3 c5 fa 6f 06 c5 fa 6f 4c 16 f0 c5 fa 7f 07 c5 RSP: 002b:00007ffc6bb5e068 EFLAGS: 00010202 RAX: 0000000020000000 RBX: 0000000000000004 RCX: 0000000000737562 RDX: 0000000000000006 RSI: 0000000075622f2e RDI: 0000000020000000 RBP: 00007f4ae5737a80 R08: 00007f4ae5400000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000009 R12: 00000000000288f4 R13: 00007ffc6bb5e170 R14: 0000000000000032 R15: fffffffffffffffe