====================================================== WARNING: possible circular locking dependency detected 4.14.307-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.4/10674 is trying to acquire lock: (sb_writers#3){.+.+}, at: [] sb_start_write include/linux/fs.h:1551 [inline] (sb_writers#3){.+.+}, at: [] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 but task is already holding lock: (&iint->mutex){+.+.}, at: [] process_measurement+0x270/0xb20 security/integrity/ima/ima_main.c:225 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&iint->mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 process_measurement+0x270/0xb20 security/integrity/ima/ima_main.c:225 do_last fs/namei.c:3435 [inline] path_openat+0x10ad/0x2970 fs/namei.c:3571 do_filp_open+0x179/0x3c0 fs/namei.c:3605 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 -> #0 (sb_writers#3){.+.+}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x64/0x260 fs/super.c:1342 sb_start_write include/linux/fs.h:1551 [inline] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 ovl_open_maybe_copy_up+0xcf/0x130 fs/overlayfs/inode.c:344 ovl_d_real+0xbc/0x350 fs/overlayfs/super.c:88 d_real include/linux/dcache.h:587 [inline] vfs_open+0x19e/0x220 fs/open.c:882 dentry_open+0xa7/0x210 fs/open.c:905 ima_calc_file_hash+0x51c/0x780 security/integrity/ima/ima_crypto.c:452 ima_collect_measurement+0x39d/0x430 security/integrity/ima/ima_api.c:227 process_measurement+0x78b/0xb20 security/integrity/ima/ima_main.c:264 do_last fs/namei.c:3435 [inline] path_openat+0x10ad/0x2970 fs/namei.c:3571 do_filp_open+0x179/0x3c0 fs/namei.c:3605 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&iint->mutex); lock(sb_writers#3); lock(&iint->mutex); lock(sb_writers#3); *** DEADLOCK *** 1 lock held by syz-executor.4/10674: #0: (&iint->mutex){+.+.}, at: [] process_measurement+0x270/0xb20 security/integrity/ima/ima_main.c:225 stack backtrace: CPU: 1 PID: 10674 Comm: syz-executor.4 Not tainted 4.14.307-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1905 [inline] check_prevs_add kernel/locking/lockdep.c:2022 [inline] validate_chain kernel/locking/lockdep.c:2464 [inline] __lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x64/0x260 fs/super.c:1342 sb_start_write include/linux/fs.h:1551 [inline] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 ovl_open_maybe_copy_up+0xcf/0x130 fs/overlayfs/inode.c:344 ovl_d_real+0xbc/0x350 fs/overlayfs/super.c:88 d_real include/linux/dcache.h:587 [inline] vfs_open+0x19e/0x220 fs/open.c:882 dentry_open+0xa7/0x210 fs/open.c:905 ima_calc_file_hash+0x51c/0x780 security/integrity/ima/ima_crypto.c:452 ima_collect_measurement+0x39d/0x430 security/integrity/ima/ima_api.c:227 process_measurement+0x78b/0xb20 security/integrity/ima/ima_main.c:264 do_last fs/namei.c:3435 [inline] path_openat+0x10ad/0x2970 fs/namei.c:3571 do_filp_open+0x179/0x3c0 fs/namei.c:3605 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 RIP: 0033:0x7f3d352e00f9 RSP: 002b:00007f3d33852168 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f3d353fff80 RCX: 00007f3d352e00f9 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000020000180 RBP: 00007f3d3533bae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff7bfa3c9f R14: 00007f3d33852300 R15: 0000000000022000 audit: type=1800 audit(1678121780.875:3): pid=10818 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.1" name="bus" dev="sda1" ino=14067 res=0 kvm: emulating exchange as write audit: type=1800 audit(1678121781.005:4): pid=10855 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.1" name="bus" dev="sda1" ino=14085 res=0 audit: type=1800 audit(1678121781.265:5): pid=10937 uid=0 auid=4294967295 ses=4294967295 op="collect_data" cause="failed(directio)" comm="syz-executor.3" name="file0" dev="sda1" ino=14022 res=0 nla_parse: 8 callbacks suppressed netlink: 168 bytes leftover after parsing attributes in process `syz-executor.2'. unregister_netdevice: waiting for ip6gre0 to become free. Usage count = -1 xt_conntrack: cannot load conntrack support for proto=2 ====================================================== WARNING: the mand mount option is being deprecated and will be removed in v5.15! ====================================================== syz-executor.0 uses obsolete (PF_INET,SOCK_PACKET) netlink: 152 bytes leftover after parsing attributes in process `syz-executor.3'.