====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc2-syzkaller-00048-g42dc814987c1 #0 Not tainted ------------------------------------------------------ syz-executor.2/17019 is trying to acquire lock: ffff88801b2ca410 (sb_writers#4){.+.+}-{0:0}, at: ovl_maybe_copy_up+0x121/0x180 fs/overlayfs/copy_up.c:1176 but task is already holding lock: ffff8880241095e0 (&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x893/0x1cc0 security/integrity/ima/ima_main.c:266 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&iint->mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 process_measurement+0x893/0x1cc0 security/integrity/ima/ima_main.c:266 ima_file_check+0xc2/0x110 security/integrity/ima/ima_main.c:543 do_open fs/namei.c:3641 [inline] path_openat+0x17a1/0x29c0 fs/namei.c:3796 do_filp_open+0x1de/0x430 fs/namei.c:3823 do_sys_openat2+0x176/0x1e0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_compat_sys_openat fs/open.c:1497 [inline] __se_compat_sys_openat fs/open.c:1495 [inline] __ia32_compat_sys_openat+0x16e/0x200 fs/open.c:1495 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 -> #0 (sb_writers#4){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1600 [inline] sb_start_write include/linux/fs.h:1675 [inline] mnt_want_write+0x6f/0x440 fs/namespace.c:403 ovl_maybe_copy_up+0x121/0x180 fs/overlayfs/copy_up.c:1176 ovl_open+0x16f/0x330 fs/overlayfs/file.c:166 do_dentry_open+0x88b/0x1730 fs/open.c:929 vfs_open fs/open.c:1063 [inline] dentry_open+0x13f/0x1d0 fs/open.c:1079 ima_calc_file_hash+0x2c4/0x4a0 security/integrity/ima/ima_crypto.c:558 ima_collect_measurement+0x5e2/0x6f0 security/integrity/ima/ima_api.c:289 process_measurement+0xc87/0x1cc0 security/integrity/ima/ima_main.c:345 ima_file_check+0xc2/0x110 security/integrity/ima/ima_main.c:543 do_open fs/namei.c:3641 [inline] path_openat+0x17a1/0x29c0 fs/namei.c:3796 do_filp_open+0x1de/0x430 fs/namei.c:3823 do_sys_openat2+0x176/0x1e0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_compat_sys_open fs/open.c:1488 [inline] __se_compat_sys_open fs/open.c:1486 [inline] __ia32_compat_sys_open+0x147/0x1d0 fs/open.c:1486 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&iint->mutex); lock(sb_writers#4); lock(&iint->mutex); rlock(sb_writers#4); *** DEADLOCK *** 1 lock held by syz-executor.2/17019: #0: ffff8880241095e0 (&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x893/0x1cc0 security/integrity/ima/ima_main.c:266 stack backtrace: CPU: 2 PID: 17019 Comm: syz-executor.2 Not tainted 6.6.0-rc2-syzkaller-00048-g42dc814987c1 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_noncircular+0x311/0x3f0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1600 [inline] sb_start_write include/linux/fs.h:1675 [inline] mnt_want_write+0x6f/0x440 fs/namespace.c:403 ovl_maybe_copy_up+0x121/0x180 fs/overlayfs/copy_up.c:1176 ovl_open+0x16f/0x330 fs/overlayfs/file.c:166 do_dentry_open+0x88b/0x1730 fs/open.c:929 vfs_open fs/open.c:1063 [inline] dentry_open+0x13f/0x1d0 fs/open.c:1079 ima_calc_file_hash+0x2c4/0x4a0 security/integrity/ima/ima_crypto.c:558 ima_collect_measurement+0x5e2/0x6f0 security/integrity/ima/ima_api.c:289 process_measurement+0xc87/0x1cc0 security/integrity/ima/ima_main.c:345 ima_file_check+0xc2/0x110 security/integrity/ima/ima_main.c:543 do_open fs/namei.c:3641 [inline] path_openat+0x17a1/0x29c0 fs/namei.c:3796 do_filp_open+0x1de/0x430 fs/namei.c:3823 do_sys_openat2+0x176/0x1e0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_compat_sys_open fs/open.c:1488 [inline] __se_compat_sys_open fs/open.c:1486 [inline] __ia32_compat_sys_open+0x147/0x1d0 fs/open.c:1486 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7f1a579 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:00000000f7f155ac EFLAGS: 00000292 ORIG_RAX: 0000000000000005 RAX: ffffffffffffffda RBX: 00000000200000c0 RCX: 0000000000000003 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi