Hello, syzbot found the following issue on: HEAD commit: 2772d7df3c93 Merge tag 'riscv-for-linus-6.5-rc2' of git://.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16849b0aa80000 kernel config: https://syzkaller.appspot.com/x/.config?x=6769a69bd0e144b4 dashboard link: https://syzkaller.appspot.com/bug?extid=39acbe8ff4cab0acdb9d 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/feba8b35b0b4/disk-2772d7df.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/d2300fb3a26e/vmlinux-2772d7df.xz kernel image: https://storage.googleapis.com/syzbot-assets/6e07347f5489/bzImage-2772d7df.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+39acbe8ff4cab0acdb9d@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.5.0-rc1-syzkaller-00201-g2772d7df3c93 #0 Not tainted ------------------------------------------------------ syz-executor.3/28959 is trying to acquire lock: ffff8880340fa450 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:781 [inline] ffff8880340fa450 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}, at: lookup_slow fs/namei.c:1706 [inline] ffff8880340fa450 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}, at: walk_component+0x33b/0x5a0 fs/namei.c:1998 but task is already holding lock: ffff888062425488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x281/0x610 fs/kernfs/file.c:325 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&of->mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 kernfs_seq_start+0x4b/0x460 fs/kernfs/file.c:154 seq_read_iter+0x2ad/0x1280 fs/seq_file.c:225 kernfs_fop_read_iter+0x4c8/0x680 fs/kernfs/file.c:279 call_read_iter include/linux/fs.h:1865 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x4e0/0x930 fs/read_write.c:470 ksys_read+0x12f/0x250 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #2 (&p->lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747 seq_read_iter+0xda/0x1280 fs/seq_file.c:182 proc_reg_read_iter+0x211/0x300 fs/proc/inode.c:305 call_read_iter include/linux/fs.h:1865 [inline] copy_splice_read+0x418/0x8f0 fs/splice.c:367 vfs_splice_read fs/splice.c:994 [inline] vfs_splice_read+0x2c8/0x3b0 fs/splice.c:963 splice_direct_to_actor+0x2a5/0xa30 fs/splice.c:1070 do_splice_direct+0x1af/0x280 fs/splice.c:1195 do_sendfile+0xb88/0x1390 fs/read_write.c:1254 __do_sys_sendfile64 fs/read_write.c:1322 [inline] __se_sys_sendfile64 fs/read_write.c:1308 [inline] __x64_sys_sendfile64+0x1d6/0x220 fs/read_write.c:1308 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 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:1494 [inline] sb_start_write include/linux/fs.h:1569 [inline] mnt_want_write+0x6f/0x440 fs/namespace.c:403 ovl_create_object+0x9e/0x2a0 fs/overlayfs/dir.c:629 lookup_open.isra.0+0x1049/0x1360 fs/namei.c:3492 open_last_lookups fs/namei.c:3560 [inline] path_openat+0x931/0x29c0 fs/namei.c:3790 do_filp_open+0x1de/0x430 fs/namei.c:3820 do_sys_openat2+0x176/0x1e0 fs/open.c:1407 do_sys_open fs/open.c:1422 [inline] __do_sys_openat fs/open.c:1438 [inline] __se_sys_openat fs/open.c:1433 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1433 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&ovl_i_mutex_dir_key[depth]){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3142 [inline] check_prevs_add kernel/locking/lockdep.c:3261 [inline] validate_chain kernel/locking/lockdep.c:3876 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5144 lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 down_read+0x9c/0x470 kernel/locking/rwsem.c:1520 inode_lock_shared include/linux/fs.h:781 [inline] lookup_slow fs/namei.c:1706 [inline] walk_component+0x33b/0x5a0 fs/namei.c:1998 lookup_last fs/namei.c:2455 [inline] path_lookupat+0x17f/0x770 fs/namei.c:2479 filename_lookup+0x1e7/0x5b0 fs/namei.c:2508 kern_path+0x35/0x50 fs/namei.c:2606 lookup_bdev+0xd9/0x280 block/bdev.c:943 resume_store+0x1d4/0x460 kernel/power/hibernate.c:1177 kobj_attr_store+0x55/0x80 lib/kobject.c:833 sysfs_kf_write+0x117/0x170 fs/sysfs/file.c:136 kernfs_fop_write_iter+0x3ff/0x610 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:1871 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x650/0xe40 fs/read_write.c:584 ksys_write+0x12f/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &ovl_i_mutex_dir_key[depth] --> &p->lock --> &of->mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&of->mutex); lock(&p->lock); lock(&of->mutex); rlock(&ovl_i_mutex_dir_key[depth]); *** DEADLOCK *** 4 locks held by syz-executor.3/28959: #0: ffff8880426b2d48 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe3/0x100 fs/file.c:1047 #1: ffff88801bcea410 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12f/0x250 fs/read_write.c:637 #2: ffff888062425488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x281/0x610 fs/kernfs/file.c:325 #3: ffff88801826ce88 (kn->active#68){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2a4/0x610 fs/kernfs/file.c:326 stack backtrace: CPU: 0 PID: 28959 Comm: syz-executor.3 Not tainted 6.5.0-rc1-syzkaller-00201-g2772d7df3c93 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023 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:2195 check_prev_add kernel/locking/lockdep.c:3142 [inline] check_prevs_add kernel/locking/lockdep.c:3261 [inline] validate_chain kernel/locking/lockdep.c:3876 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5144 lock_acquire kernel/locking/lockdep.c:5761 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726 down_read+0x9c/0x470 kernel/locking/rwsem.c:1520 inode_lock_shared include/linux/fs.h:781 [inline] lookup_slow fs/namei.c:1706 [inline] walk_component+0x33b/0x5a0 fs/namei.c:1998 lookup_last fs/namei.c:2455 [inline] path_lookupat+0x17f/0x770 fs/namei.c:2479 filename_lookup+0x1e7/0x5b0 fs/namei.c:2508 kern_path+0x35/0x50 fs/namei.c:2606 lookup_bdev+0xd9/0x280 block/bdev.c:943 resume_store+0x1d4/0x460 kernel/power/hibernate.c:1177 kobj_attr_store+0x55/0x80 lib/kobject.c:833 sysfs_kf_write+0x117/0x170 fs/sysfs/file.c:136 kernfs_fop_write_iter+0x3ff/0x610 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:1871 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x650/0xe40 fs/read_write.c:584 ksys_write+0x12f/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f3db0c7cb29 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:00007f3db1a280c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f3db0d9bf80 RCX: 00007f3db0c7cb29 RDX: 0000000000000012 RSI: 0000000020000080 RDI: 0000000000000004 RBP: 00007f3db0cc847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f3db0d9bf80 R15: 00007ffc4744d038 </TASK> PM: Image not found (code -6) --- This report is generated by a bot. 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