====================================================== WARNING: possible circular locking dependency detected 5.13.0-rc6-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor890/8445 is trying to acquire lock: ffff88802f1a93e0 (&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x3a8/0x17e0 security/integrity/ima/ima_main.c:253 but task is already holding lock: ffff88802c652460 (sb_writers#5){.+.+}-{0:0}, at: do_open fs/namei.c:3354 [inline] ffff88802c652460 (sb_writers#5){.+.+}-{0:0}, at: path_openat+0x1ad9/0x27e0 fs/namei.c:3494 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (sb_writers#5){.+.+}-{0:0}: percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1763 [inline] sb_start_write include/linux/fs.h:1833 [inline] mnt_want_write+0x6e/0x3e0 fs/namespace.c:375 ovl_maybe_copy_up+0x11f/0x190 fs/overlayfs/copy_up.c:996 ovl_open+0xba/0x270 fs/overlayfs/file.c:149 do_dentry_open+0x4b9/0x11b0 fs/open.c:826 vfs_open fs/open.c:940 [inline] dentry_open+0x132/0x1d0 fs/open.c:956 ima_calc_file_hash+0x2d2/0x4b0 security/integrity/ima/ima_crypto.c:557 ima_collect_measurement+0x4ca/0x570 security/integrity/ima/ima_api.c:252 process_measurement+0xd1c/0x17e0 security/integrity/ima/ima_main.c:330 ima_file_check+0xb9/0x100 security/integrity/ima/ima_main.c:499 do_open fs/namei.c:3363 [inline] path_openat+0x15b5/0x27e0 fs/namei.c:3494 do_filp_open+0x190/0x3d0 fs/namei.c:3521 do_sys_openat2+0x16d/0x420 fs/open.c:1187 do_sys_open fs/open.c:1203 [inline] __do_sys_open fs/open.c:1211 [inline] __se_sys_open fs/open.c:1207 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1207 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #0 (&iint->mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:2938 [inline] check_prevs_add kernel/locking/lockdep.c:3061 [inline] validate_chain kernel/locking/lockdep.c:3676 [inline] __lock_acquire+0x2a17/0x5230 kernel/locking/lockdep.c:4902 lock_acquire kernel/locking/lockdep.c:5512 [inline] lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5477 __mutex_lock_common kernel/locking/mutex.c:959 [inline] __mutex_lock+0x139/0x10c0 kernel/locking/mutex.c:1104 process_measurement+0x3a8/0x17e0 security/integrity/ima/ima_main.c:253 ima_file_check+0xb9/0x100 security/integrity/ima/ima_main.c:499 do_open fs/namei.c:3363 [inline] path_openat+0x15b5/0x27e0 fs/namei.c:3494 do_filp_open+0x190/0x3d0 fs/namei.c:3521 do_sys_openat2+0x16d/0x420 fs/open.c:1187 do_sys_open fs/open.c:1203 [inline] __do_sys_openat fs/open.c:1219 [inline] __se_sys_openat fs/open.c:1214 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1214 entry_SYSCALL_64_after_hwframe+0x44/0xae other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&iint->mutex); lock(&iint->mutex); *** DEADLOCK *** 1 lock held by syz-executor890/8445: stack backtrace: Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2129 lock_acquire kernel/locking/lockdep.c:5512 [inline] lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5477 __mutex_lock_common kernel/locking/mutex.c:959 [inline] __mutex_lock+0x139/0x10c0 kernel/locking/mutex.c:1104 process_measurement+0x3a8/0x17e0 security/integrity/ima/ima_main.c:253 ima_file_check+0xb9/0x100 security/integrity/ima/ima_main.c:499 do_open fs/namei.c:3363 [inline] path_openat+0x15b5/0x27e0 fs/namei.c:3494 do_filp_open+0x190/0x3d0 fs/namei.c:3521 do_sys_openat2+0x16d/0x420 fs/open.c:1187 do_sys_open fs/open.c:1203 [inline] __do_sys_openat fs/open.c:1219 [inline] __se_sys_openat fs/open.c:1214 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1214 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 14 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f785097e2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00000000004ca400 RCX: 0000000000444cf9 RDX: 000000000000275a RSI: 0000000020000080 RDI