DUID 00:04:03:bf:74:c9:6b:3e:f6:9c:c6:06:b2:63:41:89:5e:a1 forked to background, child pid 5499 [ 41.486981][ T5500] 8021q: adding VLAN 0 to HW filter on device bond0 [ 41.497267][ T5500] eql: remember to turn off Van-Jacobson compression on your slave devices Starting sshd: OK syzkaller Warning: Permanently added '10.128.0.236' (ED25519) to the list of known hosts. executing program syzkaller login: [ 66.213625][ T29] audit: type=1800 audit(1734514480.577:2): pid=5824 uid=0 auid=4294967295 ses=4294967295 subj=unconfined op=collect_data cause=failed comm="syz-executor134" name="features" dev="configfs" ino=5189 res=0 errno=0 [ 66.215784][ T5824] [ 66.234216][ T29] audit: type=1800 audit(1734514480.587:3): pid=5824 uid=0 auid=4294967295 ses=4294967295 subj=unconfined op=collect_data cause=failed comm="syz-executor134" name="dbroot" dev="configfs" ino=5190 res=0 errno=0 [ 66.236468][ T5824] ============================================ [ 66.236476][ T5824] WARNING: possible recursive locking detected [ 66.269033][ T5824] 6.13.0-rc3-syzkaller-00044-gaef25be35d23 #0 Not tainted [ 66.276124][ T5824] -------------------------------------------- [ 66.282249][ T5824] syz-executor134/5824 is trying to acquire lock: [ 66.288639][ T5824] ffff888025bfa478 (&p->frag_sem){.+.+}-{4:4}, at: __configfs_open_file+0xe8/0x9c0 [ 66.298036][ T5824] [ 66.298036][ T5824] but task is already holding lock: [ 66.305377][ T5824] ffff888141f09178 (&p->frag_sem){.+.+}-{4:4}, at: configfs_write_iter+0x216/0x4b0 [ 66.314666][ T5824] [ 66.314666][ T5824] other info that might help us debug this: [ 66.322701][ T5824] Possible unsafe locking scenario: [ 66.322701][ T5824] [ 66.330132][ T5824] CPU0 [ 66.333399][ T5824] ---- [ 66.336660][ T5824] lock(&p->frag_sem); [ 66.340799][ T5824] lock(&p->frag_sem); [ 66.344946][ T5824] [ 66.344946][ T5824] *** DEADLOCK *** [ 66.344946][ T5824] [ 66.353070][ T5824] May be due to missing lock nesting notation [ 66.353070][ T5824] [ 66.361390][ T5824] 4 locks held by syz-executor134/5824: [ 66.366914][ T5824] #0: ffff88801cf64420 (sb_writers#9){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 [ 66.375868][ T5824] #1: ffff888027e77688 (&buffer->mutex){+.+.}-{4:4}, at: configfs_write_iter+0x75/0x4b0 [ 66.385856][ T5824] #2: ffff888141f09178 (&p->frag_sem){.+.+}-{4:4}, at: configfs_write_iter+0x216/0x4b0 [ 66.395600][ T5824] #3: ffffffff8ee08648 (target_devices_lock){+.+.}-{4:4}, at: target_core_item_dbroot_store+0x23/0x2e0 [ 66.406734][ T5824] [ 66.406734][ T5824] stack backtrace: [ 66.412614][ T5824] CPU: 1 UID: 0 PID: 5824 Comm: syz-executor134 Not tainted 6.13.0-rc3-syzkaller-00044-gaef25be35d23 #0 [ 66.423703][ T5824] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 [ 66.433753][ T5824] Call Trace: [ 66.437019][ T5824] [ 66.439937][ T5824] dump_stack_lvl+0x116/0x1f0 [ 66.444632][ T5824] print_deadlock_bug+0x2e3/0x410 [ 66.449648][ T5824] __lock_acquire+0x2117/0x3c40 [ 66.454493][ T5824] ? __pfx___lock_acquire+0x10/0x10 [ 66.459679][ T5824] ? path_openat+0x1e6a/0x2d60 [ 66.464426][ T5824] ? do_filp_open+0x20c/0x470 [ 66.469089][ T5824] ? file_open_name+0x2a4/0x450 [ 66.473944][ T5824] ? filp_open+0x4b/0x80 [ 66.478174][ T5824] ? target_core_item_dbroot_store+0x10d/0x2e0 [ 66.484331][ T5824] ? configfs_write_iter+0x2f6/0x4b0 [ 66.489603][ T5824] ? vfs_write+0x5ae/0x1150 [ 66.494095][ T5824] ? ksys_write+0x12b/0x250 [ 66.498604][ T5824] lock_acquire.part.0+0x11b/0x380 [ 66.503703][ T5824] ? __configfs_open_file+0xe8/0x9c0 [ 66.508976][ T5824] ? __pfx_lock_acquire.part.0+0x10/0x10 [ 66.514604][ T5824] ? rcu_is_watching+0x12/0xc0 [ 66.519360][ T5824] ? trace_lock_acquire+0x14e/0x1f0 [ 66.524552][ T5824] ? __configfs_open_file+0xe8/0x9c0 [ 66.529844][ T5824] ? lock_acquire+0x2f/0xb0 [ 66.534345][ T5824] ? __configfs_open_file+0xe8/0x9c0 [ 66.539625][ T5824] down_read+0x9a/0x330 [ 66.543777][ T5824] ? __configfs_open_file+0xe8/0x9c0 [ 66.549051][ T5824] ? __pfx_down_read+0x10/0x10 [ 66.553808][ T5824] __configfs_open_file+0xe8/0x9c0 [ 66.558906][ T5824] do_dentry_open+0xf59/0x1ea0 [ 66.563659][ T5824] ? __pfx_configfs_open_file+0x10/0x10 [ 66.569191][ T5824] ? inode_permission+0xdd/0x5f0 [ 66.574144][ T5824] vfs_open+0x82/0x3f0 [ 66.578204][ T5824] ? may_open+0x1f2/0x400 [ 66.582524][ T5824] path_openat+0x1e6a/0x2d60 [ 66.587103][ T5824] ? __pfx_path_openat+0x10/0x10 [ 66.592028][ T5824] ? kasan_save_stack+0x42/0x60 [ 66.596866][ T5824] ? kasan_save_stack+0x33/0x60 [ 66.601707][ T5824] ? kasan_save_track+0x14/0x30 [ 66.606546][ T5824] ? __kasan_slab_alloc+0x89/0x90 [ 66.611577][ T5824] do_filp_open+0x20c/0x470 [ 66.616067][ T5824] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 66.622177][ T5824] ? __pfx_do_filp_open+0x10/0x10 [ 66.627211][ T5824] file_open_name+0x2a4/0x450 [ 66.631898][ T5824] ? __pfx_file_open_name+0x10/0x10 [ 66.637112][ T5824] ? kmem_cache_alloc_noprof+0x21b/0x3b0 [ 66.642749][ T5824] ? getname_kernel+0x52/0x370 [ 66.647514][ T5824] ? __pfx_target_core_item_dbroot_store+0x10/0x10 [ 66.654009][ T5824] filp_open+0x4b/0x80 [ 66.658070][ T5824] target_core_item_dbroot_store+0x10d/0x2e0 [ 66.664045][ T5824] configfs_write_iter+0x2f6/0x4b0 [ 66.669144][ T5824] vfs_write+0x5ae/0x1150 [ 66.673546][ T5824] ? __pfx_configfs_write_iter+0x10/0x10 [ 66.679177][ T5824] ? __pfx_vfs_write+0x10/0x10 [ 66.683978][ T5824] ? arch_do_signal_or_restart+0x212/0x7e0 [ 66.689784][ T5824] ksys_write+0x12b/0x250 [ 66.694109][ T5824] ? __pfx_ksys_write+0x10/0x10 [ 66.698953][ T5824] ? do_user_addr_fault+0xa4b/0x13f0 [ 66.704230][ T5824] do_syscall_64+0xcd/0x250 [ 66.708723][ T5824] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 66.714604][ T5824] RIP: 0033:0x7f187f84a9e9 [ 66.719013][ T5824] Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 00 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 [ 66.738617][ T5824] RSP: 002b:00007fffa4549828 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 66.747020][ T5824] RAX: ffffffffffffffda RBX: 00007fffa4549830 RCX: 00007f187f84a9e9 [ 66.754977][ T5824] RDX: 000000000000fdef RSI: 0000000020000000 RDI: 0000000000000004 [ 66.762933][ T5824] RBP: 00007ff