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exFAT-fs (loop5): failed to load upcase table (idx : 0x00010000, chksum : 0x206f3c15, utbl_chksum : 0xe619d30d)
======================================================
WARNING: possible circular locking dependency detected
6.1.44-syzkaller #0 Not tainted
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syz-executor.5/16511 is trying to acquire lock:
ffff0000c3d50148 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0x9c/0x124 mm/memory.c:5800

but task is already holding lock:
ffff00010f0060e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_iterate+0x144/0x2734 fs/exfat/dir.c:228

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&sbi->s_lock#2){+.+.}-{3:3}:
       __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
       exfat_get_block+0x164/0x17ec fs/exfat/inode.c:281
       do_mpage_readpage+0x5d8/0x1748 fs/mpage.c:208
       mpage_readahead+0x360/0x644 fs/mpage.c:361
       exfat_readahead+0x28/0x38 fs/exfat/inode.c:344
       read_pages+0x168/0x6a0 mm/readahead.c:161
       page_cache_ra_unbounded+0x46c/0x58c mm/readahead.c:270
       do_page_cache_ra mm/readahead.c:300 [inline]
       page_cache_ra_order+0x7fc/0x994 mm/readahead.c:560
       ondemand_readahead+0x5f8/0xb04 mm/readahead.c:682
       page_cache_sync_ra+0x350/0x3d0 mm/readahead.c:709
       page_cache_sync_readahead include/linux/pagemap.h:1213 [inline]
       filemap_get_pages mm/filemap.c:2582 [inline]
       filemap_read+0x598/0x2260 mm/filemap.c:2676
       generic_file_read_iter+0xa0/0x450 mm/filemap.c:2822
       __kernel_read+0x30c/0x6b4 fs/read_write.c:428
       kernel_read+0xd8/0x1d4 fs/read_write.c:446
       prepare_binprm fs/exec.c:1663 [inline]
       search_binary_handler fs/exec.c:1717 [inline]
       exec_binprm fs/exec.c:1774 [inline]
       bprm_execve+0x764/0x162c fs/exec.c:1843
       do_execveat_common+0x668/0x814 fs/exec.c:1948
       do_execveat fs/exec.c:2033 [inline]
       __do_sys_execveat fs/exec.c:2107 [inline]
       __se_sys_execveat fs/exec.c:2101 [inline]
       __arm64_sys_execveat+0xd0/0xec fs/exec.c:2101
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
       el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

-> #1 (mapping.invalidate_lock#3){.+.+}-{3:3}:
       down_read+0x64/0x308 kernel/locking/rwsem.c:1520
       filemap_invalidate_lock_shared include/linux/fs.h:811 [inline]
       filemap_fault+0x58c/0xf7c mm/filemap.c:3128
       __do_fault+0x11c/0x3d8 mm/memory.c:4231
       do_read_fault mm/memory.c:4582 [inline]
       do_fault mm/memory.c:4711 [inline]
       handle_pte_fault mm/memory.c:4983 [inline]
       __handle_mm_fault mm/memory.c:5125 [inline]
       handle_mm_fault+0x1f68/0x3e9c mm/memory.c:5246
       __do_page_fault arch/arm64/mm/fault.c:499 [inline]
       do_page_fault+0x330/0x890 arch/arm64/mm/fault.c:583
       do_translation_fault+0x94/0xc8 arch/arm64/mm/fault.c:667
       do_mem_abort+0x74/0x200 arch/arm64/mm/fault.c:803
       el1_abort+0x3c/0x5c arch/arm64/kernel/entry-common.c:367
       el1h_64_sync_handler+0x60/0xac arch/arm64/kernel/entry-common.c:427
       el1h_64_sync+0x64/0x68 arch/arm64/kernel/entry.S:576
       do_strncpy_from_user lib/strncpy_from_user.c:41 [inline]
       strncpy_from_user+0x224/0x54c lib/strncpy_from_user.c:139
       getname_flags+0x104/0x480 fs/namei.c:150
       getname+0x28/0x38 fs/namei.c:218
       do_sys_openat2+0xd4/0x3d8 fs/open.c:1312
       do_sys_open fs/open.c:1334 [inline]
       __do_sys_openat fs/open.c:1350 [inline]
       __se_sys_openat fs/open.c:1345 [inline]
       __arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
       el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

-> #0 (&mm->mmap_lock){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3098 [inline]
       check_prevs_add kernel/locking/lockdep.c:3217 [inline]
       validate_chain kernel/locking/lockdep.c:3832 [inline]
       __lock_acquire+0x3338/0x764c kernel/locking/lockdep.c:5056
       lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5669
       __might_fault+0xc4/0x124 mm/memory.c:5801
       filldir64+0x2d4/0x948 fs/readdir.c:335
       dir_emit_dot include/linux/fs.h:3583 [inline]
       dir_emit_dots include/linux/fs.h:3594 [inline]
       exfat_iterate+0x23c/0x2734 fs/exfat/dir.c:231
       iterate_dir+0x1f4/0x4e4
       __do_sys_getdents64 fs/readdir.c:369 [inline]
       __se_sys_getdents64 fs/readdir.c:354 [inline]
       __arm64_sys_getdents64+0x1c4/0x4a0 fs/readdir.c:354
       __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
       invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
       el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
       do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
       el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
       el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
       el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

other info that might help us debug this:

Chain exists of:
  &mm->mmap_lock --> mapping.invalidate_lock#3 --> &sbi->s_lock#2

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sbi->s_lock#2);
                               lock(mapping.invalidate_lock#3);
                               lock(&sbi->s_lock#2);
  lock(&mm->mmap_lock);

 *** DEADLOCK ***

3 locks held by syz-executor.5/16511:
 #0: ffff0000c312c5e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x9c/0xc8 fs/file.c:1046
 #1: ffff0000e26bbd30 (&sb->s_type->i_mutex_key#21){++++}-{3:3}, at: iterate_dir+0x124/0x4e4 fs/readdir.c:57
 #2: ffff00010f0060e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_iterate+0x144/0x2734 fs/exfat/dir.c:228

stack backtrace:
CPU: 0 PID: 16511 Comm: syz-executor.5 Not tainted 6.1.44-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106
 dump_stack+0x1c/0x58 lib/dump_stack.c:113
 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2056
 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2178
 check_prev_add kernel/locking/lockdep.c:3098 [inline]
 check_prevs_add kernel/locking/lockdep.c:3217 [inline]
 validate_chain kernel/locking/lockdep.c:3832 [inline]
 __lock_acquire+0x3338/0x764c kernel/locking/lockdep.c:5056
 lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5669
 __might_fault+0xc4/0x124 mm/memory.c:5801
 filldir64+0x2d4/0x948 fs/readdir.c:335
 dir_emit_dot include/linux/fs.h:3583 [inline]
 dir_emit_dots include/linux/fs.h:3594 [inline]
 exfat_iterate+0x23c/0x2734 fs/exfat/dir.c:231
 iterate_dir+0x1f4/0x4e4
 __do_sys_getdents64 fs/readdir.c:369 [inline]
 __se_sys_getdents64 fs/readdir.c:354 [inline]
 __arm64_sys_getdents64+0x1c4/0x4a0 fs/readdir.c:354
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581