program: r0 = socket$pppoe(0x18, 0x1, 0x0) connect$pppoe(r0, &(0x7f0000000080)={0x18, 0x0, {0xffff, @dev={'\xaa\xaa\xaa\xaa\xaa', 0x34}, 'netpci0\x00'}}, 0x1e) sendmmsg(r0, &(0x7f0000001cc0), 0x400000000000026, 0x0) r1 = openat$nullb(0xffffffffffffff9c, &(0x7f0000001500), 0x0, 0x0) r2 = openat$ptmx(0xffffffffffffff9c, &(0x7f0000000140), 0x0, 0x0) ioctl$TIOCSETD(r2, 0x5423, &(0x7f0000000440)=0xe) ioctl$AUTOFS_DEV_IOCTL_ASKUMOUNT(0xffffffffffffffff, 0xc018937d, &(0x7f0000000180)={{0x1, 0x1, 0x18}, '\x00'}) r3 = openat$ppp(0xffffffffffffff9c, &(0x7f0000000040), 0x0, 0x0) ioctl$EVIOCGPROP(r3, 0x40047438, &(0x7f0000000180)=""/246) ioctl$PPPIOCGFLAGS1(r3, 0x8004745a, &(0x7f0000000080)) ioctl$BLKROSET(r1, 0x80041285, &(0x7f0000000000)) r4 = socket$nl_route(0x10, 0x3, 0x0) r5 = syz_open_dev$sg(&(0x7f00000060c0), 0x0, 0x8002) ioctl$SCSI_IOCTL_GET_PCI(r5, 0x5309, 0x0) madvise(&(0x7f0000a93000/0x4000)=nil, 0x4000, 0xe) mremap(&(0x7f0000a96000/0x1000)=nil, 0x1000, 0x800000, 0x3, &(0x7f0000130000/0x800000)=nil) getsockopt$sock_cred(0xffffffffffffffff, 0x1, 0x11, 0x0, &(0x7f0000cab000)) mlock(&(0x7f0000000000/0x800000)=nil, 0x800000) mprotect(&(0x7f00004a4000/0x800000)=nil, 0x800000, 0x0) mbind(&(0x7f0000400000/0xc00000)=nil, 0xc00000, 0x0, 0x0, 0x0, 0x2) r6 = socket$packet(0x11, 0x2, 0x300) ioctl$sock_SIOCGIFINDEX(r6, 0x8933, &(0x7f0000000000)={'netdevsim0\x00', 0x0}) sendmsg$nl_route(r4, &(0x7f00000001c0)={0x0, 0x0, &(0x7f0000000440)={&(0x7f0000000980)=ANY=[@ANYBLOB="4400000010000100"/20, @ANYRES32=r7, @ANYBLOB="00000000000000001c001a8018000a140007000000000000000000a21b5b3c0000000008000400e500000000"], 0x44}}, 0x0) [ 75.854153][ T5311] Bluetooth: hci0: command tx timeout [ 75.932181][ T5326] sd 0:0:0:0: ioctl_internal_command: ILLEGAL REQUEST asc=0x24 ascq=0x0 [ 75.975497][ T5326] netlink: 8 bytes leftover after parsing attributes in process `syz.0.0'. [ 75.978897][ T5326] [ 75.979883][ T5326] ===================================== [ 75.981949][ T5326] WARNING: bad unlock balance detected! [ 75.984040][ T5326] 6.15.0-rc1-syzkaller-00025-gbec7dcbc242c #0 Not tainted [ 75.986619][ T5326] ------------------------------------- [ 75.988701][ T5326] syz.0.0/5326 is trying to release lock (&dev_instance_lock_key) at: [ 75.991712][ T5326] [] do_setlink+0xc26/0x43a0 [ 75.994118][ T5326] but there are no more locks to release! [ 75.996180][ T5326] [ 75.996180][ T5326] other info that might help us debug this: [ 75.999138][ T5326] 1 lock held by syz.0.0/5326: [ 76.000916][ T5326] #0: ffffffff900fd3c8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xd68/0x1fe0 [ 76.004225][ T5326] [ 76.004225][ T5326] stack backtrace: [ 76.006967][ T5326] CPU: 0 UID: 0 PID: 5326 Comm: syz.0.0 Not tainted 6.15.0-rc1-syzkaller-00025-gbec7dcbc242c #0 PREEMPT(full) [ 76.006985][ T5326] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 [ 76.006994][ T5326] Call Trace: [ 76.007012][ T5326] [ 76.007018][ T5326] dump_stack_lvl+0x241/0x360 [ 76.007042][ T5326] ? __pfx_dump_stack_lvl+0x10/0x10 [ 76.007059][ T5326] ? __pfx__printk+0x10/0x10 [ 76.007075][ T5326] ? print_lock+0x171/0x1a0 [ 76.007089][ T5326] ? do_setlink+0xc26/0x43a0 [ 76.007107][ T5326] print_unlock_imbalance_bug+0x185/0x1a0 [ 76.007132][ T5326] lock_release+0x1ed/0x3e0 [ 76.007146][ T5326] ? do_setlink+0xc26/0x43a0 [ 76.007164][ T5326] ? do_setlink+0xc26/0x43a0 [ 76.007180][ T5326] __mutex_unlock_slowpath+0xee/0x800 [ 76.007196][ T5326] ? rtnl_af_lookup+0x4b/0x2b0 [ 76.007212][ T5326] ? rtnl_af_lookup+0x24c/0x2b0 [ 76.007227][ T5326] ? __pfx___mutex_unlock_slowpath+0x10/0x10 [ 76.007242][ T5326] ? __pfx_validate_linkmsg+0x10/0x10 [ 76.007254][ T5326] ? lockdep_hardirqs_on+0x9d/0x150 [ 76.007269][ T5326] do_setlink+0xc26/0x43a0 [ 76.007289][ T5326] ? _printk+0xd5/0x120 [ 76.007307][ T5326] ? __pfx_do_setlink+0x10/0x10 [ 76.007327][ T5326] ? __lock_acquire+0xad5/0xd80 [ 76.007342][ T5326] ? __pfx___mutex_trylock_common+0x10/0x10 [ 76.007358][ T5326] ? rcu_is_watching+0x15/0xb0 [ 76.007372][ T5326] ? trace_contention_end+0x3c/0x120 [ 76.007387][ T5326] ? __mutex_lock+0x380/0x10c0 [ 76.007402][ T5326] ? __pfx_aa_get_newest_label+0x10/0x10 [ 76.007488][ T5326] ? rcu_is_watching+0x15/0xb0 [ 76.007504][ T5326] ? rtnl_newlink+0xd68/0x1fe0 [ 76.007520][ T5326] ? __pfx___mutex_lock+0x10/0x10 [ 76.007535][ T5326] ? ns_capable+0x8a/0xf0 [ 76.007546][ T5326] ? rtnl_link_get_net_capable+0x168/0x340 [ 76.007564][ T5326] rtnl_newlink+0x17e2/0x1fe0 [ 76.007580][ T5326] ? stack_depot_save_flags+0x43f/0x940 [ 76.007597][ T5326] ? __pfx_rtnl_newlink+0x10/0x10 [ 76.007612][ T5326] ? __netlink_deliver_tap+0x561/0x7f0 [ 76.007630][ T5326] ? netlink_deliver_tap+0x19d/0x1b0 [ 76.007646][ T5326] ? netlink_unicast+0x7c6/0x9a0 [ 76.007660][ T5326] ? netlink_sendmsg+0x8c3/0xcd0 [ 76.007675][ T5326] ? __sock_sendmsg+0x221/0x270 [ 76.007690][ T5326] ? ____sys_sendmsg+0x523/0x860 [ 76.007701][ T5326] ? __sys_sendmsg+0x271/0x360 [ 76.007712][ T5326] ? do_syscall_64+0xf3/0x230 [ 76.007725][ T5326] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 76.007744][ T5326] ? kasan_quarantine_put+0xdc/0x230 [ 76.007757][ T5326] ? lockdep_hardirqs_on+0x9d/0x150 [ 76.007770][ T5326] ? nlmon_xmit+0xaf/0x100 [ 76.007792][ T5326] ? __local_bh_enable_ip+0x168/0x200 [ 76.007805][ T5326] ? lockdep_hardirqs_on+0x9d/0x150 [ 76.007819][ T5326] ? aa_get_newest_label+0x101/0x6f0 [ 76.007837][ T5326] ? __lock_acquire+0xad5/0xd80 [ 76.007853][ T5326] ? __pfx_rtnl_newlink+0x10/0x10 [ 76.007870][ T5326] rtnetlink_rcv_msg+0x80f/0xd70 [ 76.007885][ T5326] ? rtnetlink_rcv_msg+0x1ba/0xd70 [ 76.007902][ T5326] ? __pfx_rtnetlink_rcv_msg+0x10/0x10 [ 76.007920][ T5326] ? ref_tracker_free+0x63e/0x7e0 [ 76.007935][ T5326] netlink_rcv_skb+0x208/0x480 [ 76.007952][ T5326] ? __pfx_rtnetlink_rcv_msg+0x10/0x10 [ 76.007969][ T5326] ? __pfx_netlink_rcv_skb+0x10/0x10 [ 76.007989][ T5326] ? netlink_deliver_tap+0x2e/0x1b0 [ 76.008019][ T5326] ? netlink_deliver_tap+0x2e/0x1b0 [ 76.008035][ T5326] netlink_unicast+0x7f8/0x9a0 [ 76.008050][ T5326] ? __pfx_netlink_unicast+0x10/0x10 [ 76.008064][ T5326] ? skb_put+0x114/0x1f0 [ 76.008076][ T5326] netlink_sendmsg+0x8c3/0xcd0 [ 76.008094][ T5326] ? __pfx_netlink_sendmsg+0x10/0x10 [ 76.008110][ T5326] ? aa_sock_msg_perm+0x91/0x160 [ 76.008127][ T5326] ? __pfx_netlink_sendmsg+0x10/0x10 [ 76.008142][ T5326] __sock_sendmsg+0x221/0x270 [ 76.008159][ T5326] ____sys_sendmsg+0x523/0x860 [ 76.008172][ T5326] ? __pfx_____sys_sendmsg+0x10/0x10 [ 76.008183][ T5326] ? __fget_files+0x2a/0x420 [ 76.008194][ T5326] ? __fget_files+0x2a/0x420 [ 76.008208][ T5326] __sys_sendmsg+0x271/0x360 [ 76.008220][ T5326] ? __lock_acquire+0xad5/0xd80 [ 76.008235][ T5326] ? __pfx___sys_sendmsg+0x10/0x10 [ 76.008256][ T5326] ? do_syscall_64+0xb6/0x230 [ 76.008273][ T5326] do_syscall_64+0xf3/0x230 [ 76.008286][ T5326] ? clear_bhb_loop+0x45/0xa0 [ 76.008301][ T5326] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 76.008315][ T5326] RIP: 0033:0x7fc842d8d169 [ 76.008329][ T5326] Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 [ 76.008339][ T5326] RSP: 002b:00007fc843cc5038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 76.008354][ T5326] RAX: ffffffffffffffda RBX: 00007fc842fa5fa0 RCX: 00007fc842d8d169 [ 76.008363][ T5326] RDX: 0000000000000000 RSI: 00002000000001c0 RDI: 0000000000000007 [ 76.008370][ T5326] RBP: 00007fc842e0e2a0 R08: 0000000000000000 R09: 0000000000000000 [ 76.008378][ T5326] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 76.008385][ T5326] R13: 0000000000000000 R14: 00007fc842fa5fa0 R15: 00007fff4fc8ae18 [ 76.008397][ T5326]