======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.0.0/5339 is trying to acquire lock:
ffff888031f69ea8 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline]
ffff888031f69ea8 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: blkdev_read_iter+0x2f8/0x440 block/fops.c:855

but task is already holding lock:
ffff888041cf1588 (vm_lock){++++}-{0:0}, at: lock_next_vma+0x129/0xe60 mm/mmap_lock.c:334

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (vm_lock){++++}-{0:0}:
       __vma_enter_locked+0x243/0x710 mm/mmap_lock.c:72
       __vma_start_write+0x23/0x140 mm/mmap_lock.c:104
       vma_start_write include/linux/mmap_lock.h:213 [inline]
       mprotect_fixup+0x5e1/0xa50 mm/mprotect.c:768
       setup_arg_pages+0x565/0xae0 fs/exec.c:670
       load_elf_binary+0xc5e/0x2980 fs/binfmt_elf.c:1028
       search_binary_handler fs/exec.c:1669 [inline]
       exec_binprm fs/exec.c:1701 [inline]
       bprm_execve+0x93d/0x1410 fs/exec.c:1753
       kernel_execve+0x8ef/0x9e0 fs/exec.c:1919
       try_to_run_init_process+0x13/0x60 init/main.c:1506
       kernel_init+0xad/0x1d0 init/main.c:1634
       ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

-> #1 (&mm->mmap_lock){++++}-{4:4}:
       __might_fault+0xcb/0x130 mm/memory.c:7177
       _copy_to_iter+0xf9/0x17d0 lib/iov_iter.c:196
       copy_page_to_iter+0x10c/0x1c0 lib/iov_iter.c:374
       copy_folio_to_iter include/linux/uio.h:204 [inline]
       filemap_read+0x811/0x1230 mm/filemap.c:2851
       blkdev_read_iter+0x30a/0x440 block/fops.c:856
       new_sync_read fs/read_write.c:491 [inline]
       vfs_read+0x582/0xa70 fs/read_write.c:572
       ksys_read+0x150/0x270 fs/read_write.c:715
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&sb->s_type->i_mutex_key#10){++++}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3165 [inline]
       check_prevs_add kernel/locking/lockdep.c:3284 [inline]
       validate_chain kernel/locking/lockdep.c:3908 [inline]
       __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237
       lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868
       down_read+0x47/0x2e0 kernel/locking/rwsem.c:1537
       inode_lock_shared include/linux/fs.h:1042 [inline]
       blkdev_read_iter+0x2f8/0x440 block/fops.c:855
       __kernel_read+0x504/0x9b0 fs/read_write.c:530
       freader_fetch+0x1cb/0xa00 lib/buildid.c:100
       __build_id_parse+0x168/0x870 lib/buildid.c:297
       do_procmap_query fs/proc/task_mmu.c:733 [inline]
       procfs_procmap_ioctl+0x7ae/0xd50 fs/proc/task_mmu.c:813
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:597 [inline]
       __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xe2/0xf80 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:
  &sb->s_type->i_mutex_key#10 --> &mm->mmap_lock --> vm_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  rlock(vm_lock);
                               lock(&mm->mmap_lock);
                               lock(vm_lock);
  rlock(&sb->s_type->i_mutex_key#10);

 *** DEADLOCK ***

1 lock held by syz.0.0/5339:
 #0: ffff888041cf1588 (vm_lock){++++}-{0:0}, at: lock_next_vma+0x129/0xe60 mm/mmap_lock.c:334

stack backtrace:
CPU: 0 UID: 0 PID: 5339 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:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2043
 check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3165 [inline]
 check_prevs_add kernel/locking/lockdep.c:3284 [inline]
 validate_chain kernel/locking/lockdep.c:3908 [inline]
 __lock_acquire+0x15a5/0x2cf0 kernel/locking/lockdep.c:5237
 lock_acquire+0x106/0x330 kernel/locking/lockdep.c:5868
 down_read+0x47/0x2e0 kernel/locking/rwsem.c:1537
 inode_lock_shared include/linux/fs.h:1042 [inline]
 blkdev_read_iter+0x2f8/0x440 block/fops.c:855
 __kernel_read+0x504/0x9b0 fs/read_write.c:530
 freader_fetch+0x1cb/0xa00 lib/buildid.c:100
 __build_id_parse+0x168/0x870 lib/buildid.c:297
 do_procmap_query fs/proc/task_mmu.c:733 [inline]
 procfs_procmap_ioctl+0x7ae/0xd50 fs/proc/task_mmu.c:813
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5340b9acb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5341a7b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f5340e15fa0 RCX: 00007f5340b9acb9
RDX: 0000200000000180 RSI: 00000000c0686611 RDI: 0000000000000008
RBP: 00007f5340c08bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5340e16038 R14: 00007f5340e15fa0 R15: 00007fff3f2b3da8
 </TASK>