====================================================== WARNING: possible circular locking dependency detected 6.8.0-rc7-syzkaller-g707081b61156 #0 Not tainted ------------------------------------------------------ syz-executor.1/8594 is trying to acquire lock: ffff0000d877b190 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0x9c/0x124 mm/memory.c:6079 but task is already holding lock: ffff0000eef08068 (&f->sem){+.+.}-{3:3}, at: jffs2_readdir+0x230/0x42c fs/jffs2/dir.c:135 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&f->sem){+.+.}-{3:3}: __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:608 __mutex_lock kernel/locking/mutex.c:752 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:804 jffs2_read_folio+0x6c/0xd0 fs/jffs2/file.c:125 filemap_read_folio+0x14c/0x39c mm/filemap.c:2324 filemap_fault+0xa9c/0xff4 mm/filemap.c:3337 __do_fault+0x11c/0x374 mm/memory.c:4396 do_read_fault mm/memory.c:4758 [inline] do_fault mm/memory.c:4888 [inline] do_pte_missing mm/memory.c:3745 [inline] handle_pte_fault mm/memory.c:5164 [inline] __handle_mm_fault mm/memory.c:5305 [inline] handle_mm_fault+0x3a80/0x546c mm/memory.c:5470 do_page_fault+0x32c/0xa64 arch/arm64/mm/fault.c:593 do_translation_fault+0x94/0xc8 arch/arm64/mm/fault.c:704 do_mem_abort+0x74/0x200 arch/arm64/mm/fault.c:840 el0_da+0x60/0x178 arch/arm64/kernel/entry-common.c:580 el0t_64_sync_handler+0xcc/0xfc arch/arm64/kernel/entry-common.c:733 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 -> #2 (mapping.invalidate_lock#8){.+.+}-{3:3}: down_read+0x58/0x2fc kernel/locking/rwsem.c:1526 filemap_invalidate_lock_shared include/linux/fs.h:859 [inline] filemap_fault+0x698/0xff4 mm/filemap.c:3252 __do_fault+0x11c/0x374 mm/memory.c:4396 do_read_fault mm/memory.c:4758 [inline] do_fault mm/memory.c:4888 [inline] do_pte_missing mm/memory.c:3745 [inline] handle_pte_fault mm/memory.c:5164 [inline] __handle_mm_fault mm/memory.c:5305 [inline] handle_mm_fault+0x3a80/0x546c mm/memory.c:5470 do_page_fault+0x32c/0xa64 arch/arm64/mm/fault.c:593 do_translation_fault+0x94/0xc8 arch/arm64/mm/fault.c:704 do_mem_abort+0x74/0x200 arch/arm64/mm/fault.c:840 el0_da+0x60/0x178 arch/arm64/kernel/entry-common.c:580 el0t_64_sync_handler+0xcc/0xfc arch/arm64/kernel/entry-common.c:733 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 -> #1 (&vma->vm_lock->lock){++++}-{3:3}: down_write+0x50/0xc0 kernel/locking/rwsem.c:1579 vma_start_write include/linux/mm.h:716 [inline] vma_link+0x268/0x4bc mm/mmap.c:404 insert_vm_struct+0x2bc/0x3c0 mm/mmap.c:3354 __bprm_mm_init fs/exec.c:282 [inline] bprm_mm_init fs/exec.c:384 [inline] alloc_bprm+0x488/0x934 fs/exec.c:1580 kernel_execve+0xa4/0x7e8 fs/exec.c:2009 run_init_process+0x1bc/0x1ec init/main.c:1357 try_to_run_init_process init/main.c:1364 [inline] kernel_init+0xd8/0x29c init/main.c:1497 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 -> #0 (&mm->mmap_lock){++++}-{3:3}: 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+0x3384/0x763c kernel/locking/lockdep.c:5137 lock_acquire+0x23c/0x71c kernel/locking/lockdep.c:5754 __might_fault+0xc4/0x124 mm/memory.c:6080 filldir64+0x2d4/0x948 fs/readdir.c:375 dir_emit include/linux/fs.h:3479 [inline] jffs2_readdir+0x314/0x42c fs/jffs2/dir.c:152 iterate_dir+0x3f8/0x580 fs/readdir.c:110 __do_sys_getdents64 fs/readdir.c:409 [inline] __se_sys_getdents64 fs/readdir.c:394 [inline] __arm64_sys_getdents64+0x1c4/0x4a0 fs/readdir.c:394 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:133 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:152 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 other info that might help us debug this: Chain exists of: &mm->mmap_lock --> mapping.invalidate_lock#8 --> &f->sem Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&f->sem); lock(mapping.invalidate_lock#8); lock(&f->sem); rlock(&mm->mmap_lock); *** DEADLOCK *** 3 locks held by syz-executor.1/8594: #0: ffff0000cdf06348 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x218/0x2a4 fs/file.c:1191 #1: ffff0000eef08218 (&type->i_mutex_dir_key#21){++++}-{3:3}, at: iterate_dir+0x340/0x580 fs/readdir.c:103 #2: ffff0000eef08068 (&f->sem){+.+.}-{3:3}, at: jffs2_readdir+0x230/0x42c fs/jffs2/dir.c:135 stack backtrace: CPU: 0 PID: 8594 Comm: syz-executor.1 Not tainted 6.8.0-rc7-syzkaller-g707081b61156 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:291 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:298 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 dump_stack+0x1c/0x28 lib/dump_stack.c:113 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2060 check_noncircular+0x310/0x404 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+0x3384/0x763c kernel/locking/lockdep.c:5137 lock_acquire+0x23c/0x71c kernel/locking/lockdep.c:5754 __might_fault+0xc4/0x124 mm/memory.c:6080 filldir64+0x2d4/0x948 fs/readdir.c:375 dir_emit include/linux/fs.h:3479 [inline] jffs2_readdir+0x314/0x42c fs/jffs2/dir.c:152 iterate_dir+0x3f8/0x580 fs/readdir.c:110 __do_sys_getdents64 fs/readdir.c:409 [inline] __se_sys_getdents64 fs/readdir.c:394 [inline] __arm64_sys_getdents64+0x1c4/0x4a0 fs/readdir.c:394 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:133 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:152 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598