====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.3.3685/26423 is trying to acquire lock: ffff88802894c128 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline] ffff88802894c128 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_read_iter+0x2b6/0x4f0 block/fops.c:855 but task is already holding lock: ffff8880275e6448 (vm_lock){++++}-{0:0}, at: lock_next_vma+0x10a/0xf40 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+0x23a/0x770 mm/mmap_lock.c:72 __vma_start_write+0x21/0x170 mm/mmap_lock.c:104 vma_start_write include/linux/mmap_lock.h:213 [inline] mprotect_fixup+0x345/0xb40 mm/mprotect.c:768 setup_arg_pages+0x4b6/0xb60 fs/exec.c:670 load_elf_binary+0xb75/0x5110 fs/binfmt_elf.c:1028 search_binary_handler fs/exec.c:1669 [inline] exec_binprm fs/exec.c:1701 [inline] bprm_execve fs/exec.c:1753 [inline] bprm_execve+0x8fb/0x1620 fs/exec.c:1729 kernel_execve+0x32b/0x3d0 fs/exec.c:1919 try_to_run_init_process+0x14/0x60 init/main.c:1506 kernel_init+0x14b/0x1e0 init/main.c:1634 ret_from_fork+0x754/0xaf0 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+0xde/0x140 mm/memory.c:7177 _copy_to_iter+0x117/0x1720 lib/iov_iter.c:196 copy_page_to_iter lib/iov_iter.c:374 [inline] copy_page_to_iter+0x12a/0x1e0 lib/iov_iter.c:361 copy_folio_to_iter include/linux/uio.h:204 [inline] filemap_read+0x7a9/0x10a0 mm/filemap.c:2851 blkdev_read_iter+0x2c4/0x4f0 block/fops.c:856 new_sync_read fs/read_write.c:491 [inline] vfs_read+0x825/0xb30 fs/read_write.c:572 ksys_read+0x12a/0x250 fs/read_write.c:715 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&sb->s_type->i_mutex_key#8){++++}-{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+0x14b8/0x2630 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x17c/0x330 kernel/locking/lockdep.c:5825 down_read+0x99/0x460 kernel/locking/rwsem.c:1537 inode_lock_shared include/linux/fs.h:1042 [inline] blkdev_read_iter+0x2b6/0x4f0 block/fops.c:855 __kernel_read+0x397/0xac0 fs/read_write.c:530 freader_fetch+0x1d3/0xa70 lib/buildid.c:100 __build_id_parse.isra.0+0xe4/0x6c0 lib/buildid.c:297 do_procmap_query+0xaf6/0x1050 fs/proc/task_mmu.c:733 procfs_procmap_ioctl+0x9d/0xe0 fs/proc/task_mmu.c:813 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 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#8 --> &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#8); *** DEADLOCK *** 1 lock held by syz.3.3685/26423: #0: ffff8880275e6448 (vm_lock){++++}-{0:0}, at: lock_next_vma+0x10a/0xf40 mm/mmap_lock.c:334 stack backtrace: CPU: 2 UID: 0 PID: 26423 Comm: syz.3.3685 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_circular_bug.cold+0x178/0x1c7 kernel/locking/lockdep.c:2043 check_noncircular+0x146/0x160 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+0x14b8/0x2630 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x17c/0x330 kernel/locking/lockdep.c:5825 down_read+0x99/0x460 kernel/locking/rwsem.c:1537 inode_lock_shared include/linux/fs.h:1042 [inline] blkdev_read_iter+0x2b6/0x4f0 block/fops.c:855 __kernel_read+0x397/0xac0 fs/read_write.c:530 freader_fetch+0x1d3/0xa70 lib/buildid.c:100 __build_id_parse.isra.0+0xe4/0x6c0 lib/buildid.c:297 do_procmap_query+0xaf6/0x1050 fs/proc/task_mmu.c:733 procfs_procmap_ioctl+0x9d/0xe0 fs/proc/task_mmu.c:813 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f70e699aeb9 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:00007f70e7825028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f70e6c15fa0 RCX: 00007f70e699aeb9 RDX: 0000200000000180 RSI: 00000000c0686611 RDI: 0000000000000003 RBP: 00007f70e6a08c1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f70e6c16038 R14: 00007f70e6c15fa0 R15: 00007ffea0051188