On Fri, Sep 29, 2023 at 6:06 AM syzbot <syzbot+e8628856801e9809216f@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit: 940fcc189c51 Add linux-next specific files for 20230921 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=12dea70e680000 > kernel config: https://syzkaller.appspot.com/x/.config?x=1f140ae6e669ac24 > dashboard link: https://syzkaller.appspot.com/bug?extid=e8628856801e9809216f > compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 > > Unfortunately, I don't have any reproducer for this issue yet. > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/b8921b235c24/disk-940fcc18.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/c80a9f6bcdd4/vmlinux-940fcc18.xz > kernel image: https://storage.googleapis.com/syzbot-assets/ed10a4df6950/bzImage-940fcc18.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+e8628856801e9809216f@xxxxxxxxxxxxxxxxxxxxxxxxx > > ====================================================== > WARNING: possible circular locking dependency detected > 6.6.0-rc2-next-20230921-syzkaller #0 Not tainted > ------------------------------------------------------ > syz-executor.3/15498 is trying to acquire lock: > ffff88808e717968 (&ovl_i_lock_key[depth]#2){+.+.}-{3:3}, at: ovl_inode_lock_interruptible fs/overlayfs/overlayfs.h:630 [inline] > ffff88808e717968 (&ovl_i_lock_key[depth]#2){+.+.}-{3:3}, at: ovl_copy_up_start+0x4d/0x290 fs/overlayfs/util.c:692 > > but task is already holding lock: > ffff88801d8b13e0 (&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: > > -> #2 (&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:3622 [inline] > path_openat+0x17a1/0x29c0 fs/namei.c:3777 > do_filp_open+0x1de/0x430 fs/namei.c:3804 > do_sys_openat2+0x176/0x1e0 fs/open.c:1422 > do_sys_open fs/open.c:1437 [inline] > __do_sys_open fs/open.c:1445 [inline] > __se_sys_open fs/open.c:1441 [inline] > __x64_sys_open+0x154/0x1e0 fs/open.c:1441 > do_syscall_x64 arch/x86/entry/common.c:51 [inline] > do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81 > entry_SYSCALL_64_after_hwframe+0x63/0xcd > > -> #1 (sb_writers#4){.+.+}-{0:0}: > percpu_down_read include/linux/percpu-rwsem.h:51 [inline] > __sb_start_write include/linux/fs.h:1572 [inline] > sb_start_write include/linux/fs.h:1647 [inline] > ovl_start_write+0xfe/0x2d0 fs/overlayfs/util.c:31 > ovl_copy_up_tmpfile fs/overlayfs/copy_up.c:830 [inline] > ovl_do_copy_up fs/overlayfs/copy_up.c:945 [inline] > ovl_copy_up_one+0x16a5/0x3250 fs/overlayfs/copy_up.c:1137 > ovl_copy_up_flags+0x189/0x200 fs/overlayfs/copy_up.c:1192 > ovl_xattr_set+0x387/0x4e0 fs/overlayfs/xattrs.c:56 > __vfs_setxattr+0x173/0x1d0 fs/xattr.c:201 > __vfs_setxattr_noperm+0x127/0x5e0 fs/xattr.c:235 > __vfs_setxattr_locked+0x17e/0x250 fs/xattr.c:296 > vfs_setxattr+0x146/0x350 fs/xattr.c:322 > do_setxattr+0x142/0x170 fs/xattr.c:630 > setxattr+0x159/0x170 fs/xattr.c:653 > path_setxattr+0x1a3/0x1d0 fs/xattr.c:672 > __do_sys_setxattr fs/xattr.c:688 [inline] > __se_sys_setxattr fs/xattr.c:684 [inline] > __x64_sys_setxattr+0xc4/0x160 fs/xattr.c:684 > do_syscall_x64 arch/x86/entry/common.c:51 [inline] > do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81 > entry_SYSCALL_64_after_hwframe+0x63/0xcd > > -> #0 (&ovl_i_lock_key[depth]#2){+.+.}-{3:3}: > 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 > __mutex_lock_common kernel/locking/mutex.c:603 [inline] > __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 > ovl_inode_lock_interruptible fs/overlayfs/overlayfs.h:630 [inline] > ovl_copy_up_start+0x4d/0x290 fs/overlayfs/util.c:692 > ovl_copy_up_one+0x598/0x3250 fs/overlayfs/copy_up.c:1130 > ovl_copy_up_flags+0x189/0x200 fs/overlayfs/copy_up.c:1192 > ovl_maybe_copy_up+0x124/0x160 fs/overlayfs/copy_up.c:1222 > 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:3622 [inline] > path_openat+0x17a1/0x29c0 fs/namei.c:3777 > do_filp_open+0x1de/0x430 fs/namei.c:3804 > do_sys_openat2+0x176/0x1e0 fs/open.c:1422 > do_sys_open fs/open.c:1437 [inline] > __do_sys_openat fs/open.c:1453 [inline] > __se_sys_openat fs/open.c:1448 [inline] > __x64_sys_openat+0x175/0x210 fs/open.c:1448 > do_syscall_x64 arch/x86/entry/common.c:51 [inline] > do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81 > entry_SYSCALL_64_after_hwframe+0x63/0xcd > > other info that might help us debug this: > > Chain exists of: > &ovl_i_lock_key[depth]#2 --> sb_writers#4 --> &iint->mutex > > Possible unsafe locking scenario: > > CPU0 CPU1 > ---- ---- > lock(&iint->mutex); > lock(sb_writers#4); > lock(&iint->mutex); > lock(&ovl_i_lock_key[depth]#2); > > *** DEADLOCK *** > > 1 lock held by syz-executor.3/15498: > #0: ffff88801d8b13e0 (&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x893/0x1cc0 security/integrity/ima/ima_main.c:266 > > stack backtrace: > CPU: 0 PID: 15498 Comm: syz-executor.3 Not tainted 6.6.0-rc2-next-20230921-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 > Call Trace: > <TASK> > __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 > __mutex_lock_common kernel/locking/mutex.c:603 [inline] > __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 > ovl_inode_lock_interruptible fs/overlayfs/overlayfs.h:630 [inline] > ovl_copy_up_start+0x4d/0x290 fs/overlayfs/util.c:692 > ovl_copy_up_one+0x598/0x3250 fs/overlayfs/copy_up.c:1130 > ovl_copy_up_flags+0x189/0x200 fs/overlayfs/copy_up.c:1192 > ovl_maybe_copy_up+0x124/0x160 fs/overlayfs/copy_up.c:1222 > 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:3622 [inline] > path_openat+0x17a1/0x29c0 fs/namei.c:3777 > do_filp_open+0x1de/0x430 fs/namei.c:3804 > do_sys_openat2+0x176/0x1e0 fs/open.c:1422 > do_sys_open fs/open.c:1437 [inline] > __do_sys_openat fs/open.c:1453 [inline] > __se_sys_openat fs/open.c:1448 [inline] > __x64_sys_openat+0x175/0x210 fs/open.c:1448 > do_syscall_x64 arch/x86/entry/common.c:51 [inline] > do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81 > entry_SYSCALL_64_after_hwframe+0x63/0xcd > RIP: 0033:0x7f30bf67cae9 > Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48 > RSP: 002b:00007f30c03990c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 > RAX: ffffffffffffffda RBX: 00007f30bf79c050 RCX: 00007f30bf67cae9 > RDX: 0000000000008443 RSI: 0000000020004280 RDI: ffffffffffffff9c > RBP: 00007f30bf6c847a R08: 0000000000000000 R09: 0000000000000000 > R10: 00000000000000cc R11: 0000000000000246 R12: 0000000000000000 > R13: 000000000000006e R14: 00007f30bf79c050 R15: 00007ffce77ebe68 > </TASK> > > This looks like a new report that started after: 346f114cc506 ovl: reorder ovl_want_write() after ovl_inode_lock() but the root cause looks like the same old false positive #syz dup: possible deadlock in mnt_want_write (2)