====================================================== WARNING: possible circular locking dependency detected 6.12.0-rc5-syzkaller-00005-ge42b1a9a2557 #0 Not tainted ------------------------------------------------------ syz.0.250/6921 is trying to acquire lock: ffff88804c593a98 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock_killable include/linux/mmap_lock.h:153 [inline] ffff88804c593a98 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:6112 [inline] ffff88804c593a98 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x3a9/0x6a0 mm/memory.c:6163 but task is already holding lock: ffff8880123771d0 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] ffff8880123771d0 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: shmem_file_write_iter+0x86/0x140 mm/shmem.c:3206 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}: down_write+0x93/0x200 kernel/locking/rwsem.c:1577 inode_lock include/linux/fs.h:815 [inline] process_measurement+0x39c/0x2370 security/integrity/ima/ima_main.c:250 ima_file_mmap+0x146/0x1d0 security/integrity/ima/ima_main.c:455 security_mmap_file+0x8bd/0x990 security/security.c:2979 __do_sys_remap_file_pages+0x526/0x900 mm/mmap.c:1702 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #0 (&mm->mmap_lock){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain kernel/locking/lockdep.c:3904 [inline] __lock_acquire+0x250b/0x3ce0 kernel/locking/lockdep.c:5202 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5825 down_read_killable+0x9d/0x380 kernel/locking/rwsem.c:1547 mmap_read_lock_killable include/linux/mmap_lock.h:153 [inline] get_mmap_lock_carefully mm/memory.c:6112 [inline] lock_mm_and_find_vma+0x3a9/0x6a0 mm/memory.c:6163 do_user_addr_fault+0x2b5/0x13f0 arch/x86/mm/fault.c:1361 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 fault_in_readable+0x160/0x200 mm/gup.c:2235 fault_in_iov_iter_readable+0x101/0x2c0 lib/iov_iter.c:94 generic_perform_write+0x21b/0x920 mm/filemap.c:4044 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3216 new_sync_write fs/read_write.c:590 [inline] vfs_write+0x5ae/0x1150 fs/read_write.c:683 ksys_write+0x12f/0x260 fs/read_write.c:736 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#12); lock(&mm->mmap_lock); lock(&sb->s_type->i_mutex_key#12); rlock(&mm->mmap_lock); *** DEADLOCK *** 3 locks held by syz.0.250/6921: #0: ffff888026b7d7b8 (&f->f_pos_lock){+.+.}-{3:3}, at: fdget_pos+0x24c/0x360 fs/file.c:1160 #1: ffff88802244e420 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x12f/0x260 fs/read_write.c:736 #2: ffff8880123771d0 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:815 [inline] #2: ffff8880123771d0 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: shmem_file_write_iter+0x86/0x140 mm/shmem.c:3206 stack backtrace: CPU: 3 UID: 0 PID: 6921 Comm: syz.0.250 Not tainted 6.12.0-rc5-syzkaller-00005-ge42b1a9a2557 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x419/0x5d0 kernel/locking/lockdep.c:2074 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain kernel/locking/lockdep.c:3904 [inline] __lock_acquire+0x250b/0x3ce0 kernel/locking/lockdep.c:5202 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5825 down_read_killable+0x9d/0x380 kernel/locking/rwsem.c:1547 mmap_read_lock_killable include/linux/mmap_lock.h:153 [inline] get_mmap_lock_carefully mm/memory.c:6112 [inline] lock_mm_and_find_vma+0x3a9/0x6a0 mm/memory.c:6163 do_user_addr_fault+0x2b5/0x13f0 arch/x86/mm/fault.c:1361 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:fault_in_readable+0x160/0x200 mm/gup.c:2235 Code: 42 e8 45 31 f6 e8 70 36 ba ff 48 39 eb 75 13 eb 2e e8 64 36 ba ff 48 81 c3 00 10 00 00 48 39 eb 74 1d e8 53 36 ba ff 45 89 f7 <8a> 03 31 ff 44 89 fe 88 44 24 28 e8 80 38 ba ff 45 85 ff 74 d2 e8 RSP: 0018:ffffc9000e9c7b08 EFLAGS: 00050246 RAX: 0000000000040000 RBX: 00000000205c9000 RCX: ffffc9000c202000 RDX: 0000000000040000 RSI: ffffffff81d26f9d RDI: 0000000000000007 RBP: 0000000020600000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000037000 R13: 00000000205c9000 R14: 0000000000000000 R15: 0000000000000000 fault_in_iov_iter_readable+0x101/0x2c0 lib/iov_iter.c:94 generic_perform_write+0x21b/0x920 mm/filemap.c:4044 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3216 new_sync_write fs/read_write.c:590 [inline] vfs_write+0x5ae/0x1150 fs/read_write.c:683 ksys_write+0x12f/0x260 fs/read_write.c:736 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7f00579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f568655c EFLAGS: 00000296 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000000 RDX: 000000000208e24b RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess): 0: 42 e8 45 31 f6 e8 rex.X call 0xe8f6314b 6: 70 36 jo 0x3e 8: ba ff 48 39 eb mov $0xeb3948ff,%edx d: 75 13 jne 0x22 f: eb 2e jmp 0x3f 11: e8 64 36 ba ff call 0xffba367a 16: 48 81 c3 00 10 00 00 add $0x1000,%rbx 1d: 48 39 eb cmp %rbp,%rbx 20: 74 1d je 0x3f 22: e8 53 36 ba ff call 0xffba367a 27: 45 89 f7 mov %r14d,%r15d * 2a: 8a 03 mov (%rbx),%al <-- trapping instruction 2c: 31 ff xor %edi,%edi 2e: 44 89 fe mov %r15d,%esi 31: 88 44 24 28 mov %al,0x28(%rsp) 35: e8 80 38 ba ff call 0xffba38ba 3a: 45 85 ff test %r15d,%r15d 3d: 74 d2 je 0x11 3f: e8 .byte 0xe8