ci2 starts bisection 2023-05-25 15:16:23.32119361 +0000 UTC m=+17757.717404127 bisecting fixing commit since 8020ae3c051d1c9ec7b7a872e226f9720547649b building syzkaller on 7939252e4ddf50bbb9912069a40d32f6c83c4f8e ensuring issue is reproducible on original commit 8020ae3c051d1c9ec7b7a872e226f9720547649b testing commit 8020ae3c051d1c9ec7b7a872e226f9720547649b gcc compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 4191e3d3e9f94ff1fd364fd4063d58bd5463a0c2beb6a1dd239874382cb1ee53 all runs: crashed: possible deadlock in mnt_want_write testing current HEAD 1fe619a7d25218e9b9fdcce9fcac6a05cd62abed testing commit 1fe619a7d25218e9b9fdcce9fcac6a05cd62abed gcc compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 09bf0f6ad364c4cae922430514b60426bbdd68d1dbb52e05e6b1a7a1e65d5a64 all runs: crashed: possible deadlock in mnt_want_write crash still not fixed/happens on the oldest tested release revisions tested: 2, total time: 34m40.235575434s (build: 27m49.192058212s, test: 6m15.339151412s) crash still not fixed on HEAD or HEAD had kernel test errors commit msg: Linux 5.15.113 crash: possible deadlock in mnt_want_write ====================================================== WARNING: possible circular locking dependency detected 5.15.113-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/3952 is trying to acquire lock: ffff888020c58460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x36/0x70 fs/namespace.c:377 but task is already holding lock: ffff8880183e9e00 (&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x61b/0x1510 security/integrity/ima/ima_main.c:260 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&iint->mutex){+.+.}-{3:3}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622 __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 process_measurement+0x61b/0x1510 security/integrity/ima/ima_main.c:260 ima_file_check+0xeb/0x170 security/integrity/ima/ima_main.c:519 do_open fs/namei.c:3540 [inline] path_openat+0x2336/0x28d0 fs/namei.c:3672 do_filp_open+0x208/0x400 fs/namei.c:3699 do_sys_openat2+0x10b/0x430 fs/open.c:1211 do_sys_open fs/open.c:1227 [inline] __do_sys_openat fs/open.c:1243 [inline] __se_sys_openat fs/open.c:1238 [inline] __x64_sys_openat+0x209/0x250 fs/open.c:1238 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb -> #0 (sb_writers#5){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain+0x1646/0x58b0 kernel/locking/lockdep.c:3787 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1742 [inline] sb_start_write+0x49/0x140 include/linux/fs.h:1812 mnt_want_write+0x36/0x70 fs/namespace.c:377 ovl_maybe_copy_up+0xb1/0x100 fs/overlayfs/copy_up.c:1074 ovl_open+0x86/0x1f0 fs/overlayfs/file.c:150 do_dentry_open+0x60a/0xcc0 fs/open.c:826 vfs_open fs/open.c:956 [inline] dentry_open+0xb5/0xf0 fs/open.c:972 ima_calc_file_hash+0x133/0x1680 security/integrity/ima/ima_crypto.c:558 ima_collect_measurement+0x21a/0x460 security/integrity/ima/ima_api.c:254 process_measurement+0xb72/0x1510 security/integrity/ima/ima_main.c:337 ima_file_check+0xeb/0x170 security/integrity/ima/ima_main.c:519 do_open fs/namei.c:3540 [inline] path_openat+0x2336/0x28d0 fs/namei.c:3672 do_filp_open+0x208/0x400 fs/namei.c:3699 do_sys_openat2+0x10b/0x430 fs/open.c:1211 do_sys_open fs/open.c:1227 [inline] __do_sys_openat fs/open.c:1243 [inline] __se_sys_openat fs/open.c:1238 [inline] __x64_sys_openat+0x209/0x250 fs/open.c:1238 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&iint->mutex); lock(sb_writers#5); lock(&iint->mutex); lock(sb_writers#5); *** DEADLOCK *** 1 lock held by syz-executor.0/3952: #0: ffff8880183e9e00 (&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x61b/0x1510 security/integrity/ima/ima_main.c:260 stack backtrace: CPU: 1 PID: 3952 Comm: syz-executor.0 Not tainted 5.15.113-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/16/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x163/0x213 lib/dump_stack.c:106 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain+0x1646/0x58b0 kernel/locking/lockdep.c:3787 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1742 [inline] sb_start_write+0x49/0x140 include/linux/fs.h:1812 mnt_want_write+0x36/0x70 fs/namespace.c:377 ovl_maybe_copy_up+0xb1/0x100 fs/overlayfs/copy_up.c:1074 ovl_open+0x86/0x1f0 fs/overlayfs/file.c:150 do_dentry_open+0x60a/0xcc0 fs/open.c:826 vfs_open fs/open.c:956 [inline] dentry_open+0xb5/0xf0 fs/open.c:972 ima_calc_file_hash+0x133/0x1680 security/integrity/ima/ima_crypto.c:558 ima_collect_measurement+0x21a/0x460 security/integrity/ima/ima_api.c:254 process_measurement+0xb72/0x1510 security/integrity/ima/ima_main.c:337 ima_file_check+0xeb/0x170 security/integrity/ima/ima_main.c:519 do_open fs/namei.c:3540 [inline] path_openat+0x2336/0x28d0 fs/namei.c:3672 do_filp_open+0x208/0x400 fs/namei.c:3699 do_sys_openat2+0x10b/0x430 fs/open.c:1211 do_sys_open fs/open.c:1227 [inline] __do_sys_openat fs/open.c:1243 [inline] __se_sys_openat fs/open.c:1238 [inline] __x64_sys_openat+0x209/0x250 fs/open.c:1238 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7fbadb2a60f9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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:00007fbada618168 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fbadb3c5f80 RCX: 00007fbadb2a60f9 RDX: 0000000000000003 RSI: 0000000020000340 RDI: 0000000000000006 RBP: 00007fbadb301b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd44c2a91f R14: 00007fbada618300 R15: 0000000000022000