====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.0.0/5330 is trying to acquire lock: ffff888013a0c740 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x21c/0x1df0 fs/hfsplus/extents.c:457 but task is already holding lock: ffff888013ae40a8 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfsplus_find_init+0x179/0x2e0 fs/hfsplus/bfind.c:29 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&tree->tree_lock/1){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x19d/0x1550 kernel/locking/mutex.c:821 hfsplus_find_init+0x179/0x2e0 fs/hfsplus/bfind.c:29 hfsplus_file_truncate+0x3e0/0xd20 fs/hfsplus/extents.c:585 hfsplus_setattr+0x1b5/0x260 fs/hfsplus/inode.c:328 notify_change+0xbba/0xea0 fs/attr.c:556 do_truncate+0x1c2/0x250 fs/open.c:68 handle_truncate fs/namei.c:4329 [inline] do_open fs/namei.c:4870 [inline] path_openat+0x15b5/0x1d60 fs/namei.c:5029 do_file_open+0x23e/0x4a0 fs/namei.c:5058 do_sys_openat2+0x115/0x200 fs/open.c:1417 do_sys_open fs/open.c:1423 [inline] __do_sys_open fs/open.c:1431 [inline] __se_sys_open fs/open.c:1427 [inline] __x64_sys_open+0x11e/0x150 fs/open.c:1427 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&HFSPLUS_I(inode)->extents_lock){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3209 [inline] check_prevs_add kernel/locking/lockdep.c:3328 [inline] validate_chain kernel/locking/lockdep.c:3952 [inline] __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x19d/0x1550 kernel/locking/mutex.c:821 hfsplus_file_extend+0x21c/0x1df0 fs/hfsplus/extents.c:457 hfsplus_bmap_reserve+0x170/0x590 fs/hfsplus/btree.c:512 __hfsplus_ext_write_extent+0x295/0x690 fs/hfsplus/extents.c:104 __hfsplus_ext_cache_extent+0x81/0xbd0 fs/hfsplus/extents.c:190 hfsplus_ext_read_extent fs/hfsplus/extents.c:222 [inline] hfsplus_file_extend+0x502/0x1df0 fs/hfsplus/extents.c:461 hfsplus_get_block+0x41f/0x1610 fs/hfsplus/extents.c:249 __block_write_begin_int+0x6c2/0x1900 fs/buffer.c:2030 block_write_begin fs/buffer.c:2144 [inline] cont_write_begin+0x71b/0xac0 fs/buffer.c:2506 hfsplus_write_begin+0x126/0x1e0 fs/hfsplus/inode.c:56 generic_perform_write+0x2d5/0x8f0 mm/filemap.c:4374 generic_file_write_iter+0xae/0x330 mm/filemap.c:4517 __kernel_write_iter+0x44a/0x8f0 fs/read_write.c:621 dump_emit_page fs/coredump.c:1293 [inline] dump_user_range+0xc19/0x12c0 fs/coredump.c:1367 elf_core_dump+0x3485/0x3a90 fs/binfmt_elf.c:2106 coredump_write+0x1290/0x1960 fs/coredump.c:1047 do_coredump fs/coredump.c:1126 [inline] vfs_coredump+0x3764/0x4520 fs/coredump.c:1195 get_signal+0x1094/0x12c0 kernel/signal.c:3097 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline] ret_from_fork+0x593/0xb70 arch/x86/kernel/process.c:167 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&tree->tree_lock/1); lock(&HFSPLUS_I(inode)->extents_lock); lock(&tree->tree_lock/1); lock(&HFSPLUS_I(inode)->extents_lock); *** DEADLOCK *** locks held by syz.0.0/5330: 4, last CPU#0: #0: ffff888032f22460 (sb_writers#12){.+.+}-{0:0}, at: do_coredump fs/coredump.c:1126 [inline] #0: ffff888032f22460 (sb_writers#12){.+.+}-{0:0}, at: vfs_coredump+0x3764/0x4520 fs/coredump.c:1195 #1: ffff888013368f18 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline] #1: ffff888013368f18 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: generic_file_write_iter+0x82/0x330 mm/filemap.c:4514 #2: ffff888013368d80 (&hip->extents_lock){+.+.}-{4:4}, at: hfsplus_file_extend+0x21c/0x1df0 fs/hfsplus/extents.c:457 #3: ffff888013ae40a8 (&tree->tree_lock/1){+.+.}-{4:4}, at: hfsplus_find_init+0x179/0x2e0 fs/hfsplus/bfind.c:29 stack backtrace: CPU: 0 UID: 0 PID: 5330 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2087 check_noncircular+0x12f/0x150 kernel/locking/lockdep.c:2219 check_prev_add kernel/locking/lockdep.c:3209 [inline] check_prevs_add kernel/locking/lockdep.c:3328 [inline] validate_chain kernel/locking/lockdep.c:3952 [inline] __lock_acquire+0x164c/0x2de0 kernel/locking/lockdep.c:5288 lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942 __mutex_lock_common kernel/locking/mutex.c:646 [inline] __mutex_lock+0x19d/0x1550 kernel/locking/mutex.c:821 hfsplus_file_extend+0x21c/0x1df0 fs/hfsplus/extents.c:457 hfsplus_bmap_reserve+0x170/0x590 fs/hfsplus/btree.c:512 __hfsplus_ext_write_extent+0x295/0x690 fs/hfsplus/extents.c:104 __hfsplus_ext_cache_extent+0x81/0xbd0 fs/hfsplus/extents.c:190 hfsplus_ext_read_extent fs/hfsplus/extents.c:222 [inline] hfsplus_file_extend+0x502/0x1df0 fs/hfsplus/extents.c:461 hfsplus_get_block+0x41f/0x1610 fs/hfsplus/extents.c:249 __block_write_begin_int+0x6c2/0x1900 fs/buffer.c:2030 block_write_begin fs/buffer.c:2144 [inline] cont_write_begin+0x71b/0xac0 fs/buffer.c:2506 hfsplus_write_begin+0x126/0x1e0 fs/hfsplus/inode.c:56 generic_perform_write+0x2d5/0x8f0 mm/filemap.c:4374 generic_file_write_iter+0xae/0x330 mm/filemap.c:4517 __kernel_write_iter+0x44a/0x8f0 fs/read_write.c:621 dump_emit_page fs/coredump.c:1293 [inline] dump_user_range+0xc19/0x12c0 fs/coredump.c:1367 elf_core_dump+0x3485/0x3a90 fs/binfmt_elf.c:2106 coredump_write+0x1290/0x1960 fs/coredump.c:1047 do_coredump fs/coredump.c:1126 [inline] vfs_coredump+0x3764/0x4520 fs/coredump.c:1195 get_signal+0x1094/0x12c0 kernel/signal.c:3097 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline] ret_from_fork+0x593/0xb70 arch/x86/kernel/process.c:167 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245