panic: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/netinet/if_ether.c", line 758 Stopped at db_enter+0x1c: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 523255 45591 0 0x14000 0x200 1 softnet0 *327537 59515 0 0x14000 0x40000200 0 softclock db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827a1ffc) at panic+0x17b sys/kern/subr_prf.c:198 __assert(ffffffff82820837,ffffffff8281e421,2f6,ffffffff82770152) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd8075bd26a8) at arptfree+0x132 sys/netinet/if_ether.c:758 arptimer(ffffffff82d0bb70) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82d0bb70) at timeout_run+0xd0 sys/kern/kern_timeout.c:640 softclock_thread(ffff800021168aa0) at softclock_thread+0x124 sys/kern/kern_timeout.c:763 end trace frame: 0x0, count: 8 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs. ddb{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic *cpu0: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/netinet/if_ether.c", line 758 ddb{0}> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827a1ffc) at panic+0x17b sys/kern/subr_prf.c:198 __assert(ffffffff82820837,ffffffff8281e421,2f6,ffffffff82770152) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd8075bd26a8) at arptfree+0x132 sys/netinet/if_ether.c:758 arptimer(ffffffff82d0bb70) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82d0bb70) at timeout_run+0xd0 sys/kern/kern_timeout.c:640 softclock_thread(ffff800021168aa0) at softclock_thread+0x124 sys/kern/kern_timeout.c:763 end trace frame: 0x0, count: -7 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800021175d20 rbx 0xffffffff82b80ba7 cpu_info_full_primary+0x2ba7 rdx 0 rcx 0xffff800021168aa0 rax 0xffffffff82b7fff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x7f0cda828addedc0 r11 0xbe497320d6067d3d r12 0xffffffff82b809a8 cpu_info_full_primary+0x29a8 r13 0 r14 0 r15 0x1 rip 0xffffffff8253d86c db_enter+0x1c cs 0x8 rflags 0x246 rsp 0xffff800021175d10 ss 0x10 db_enter+0x1c: addq $0x8,%rsp ddb{0}> show proc PROC (softclock) tid=327537 pid=59515 tcnt=1 stat=onproc flags process=14000 proc=40000200 runpri=0, usrpri=50, slppri=0, nice=20 wchan=0x0, wmesg=, ps_single=0x0 forw=0xffffffffffffffff, list=0xffff800021169298,0xffff8000211682b8 process=0xffff8000ffffe180 user=0xffff800021170000, vmspace=0xffffffff82d193d8 estcpu=0, cpticks=2, pctcpu=0.0, user=0, sys=2, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 58039 255752 31166 0 2 0 syz-executor.2 39021 302399 84206 0 3 0x80 nanoslp syz-executor.6 39021 209296 84206 0 3 0x4000080 kqread syz-executor.6 39021 519444 84206 0 3 0x4000080 fsleep syz-executor.6 82532 404552 32406 0 3 0x80 nanoslp syz-executor.7 82532 380679 32406 0 3 0x4000080 piperd syz-executor.7 82532 315942 32406 0 3 0x4000080 fsleep syz-executor.7 59783 414583 61141 0 3 0x80 nanoslp syz-executor.3 59783 222917 61141 0 3 0x4000080 pipewr syz-executor.3 59783 434817 61141 0 3 0x4000080 pipewr syz-executor.3 78142 282759 63645 0 2 0 syz-executor.5 78142 298537 63645 0 3 0x4000080 kqread syz-executor.5 63645 353181 52144 0 3 0x82 nanoslp syz-executor.5 84206 106552 52144 0 3 0x82 nanoslp syz-executor.6 31166 424574 52144 0 3 0x82 nanoslp syz-executor.2 32406 178724 52144 0 3 0x82 nanoslp syz-executor.7 61141 479866 52144 0 3 0x82 nanoslp syz-executor.3 48338 478260 0 0 3 0x14200 acct acct 14807 44609 0 0 3 0x14280 nfsidl nfsio 43692 129620 0 0 3 0x14280 nfsidl nfsio 12433 266508 0 0 3 0x14280 nfsidl nfsio 95623 194044 0 0 3 0x14280 nfsidl nfsio 53905 139500 0 0 3 0x14280 nfsidl nfsio 71714 509801 0 0 3 0x14280 nfsidl nfsio 70573 319918 0 0 3 0x14280 nfsidl nfsio 50873 290028 0 0 3 0x14280 nfsidl nfsio 99773 420980 0 0 3 0x14280 nfsidl nfsio 93825 300554 0 0 3 0x14280 nfsidl nfsio 72285 201841 0 0 3 0x14280 nfsidl nfsio 10897 247781 0 0 3 0x14280 nfsidl nfsio 5677 66554 0 0 3 0x14280 nfsidl nfsio 55731 232068 0 0 3 0x14280 nfsidl nfsio 83252 240296 0 0 3 0x14280 nfsidl nfsio 66446 356727 0 0 3 0x14280 nfsidl nfsio 94899 243136 0 0 3 0x14280 nfsidl nfsio 30880 399144 0 0 3 0x14280 nfsidl nfsio 5658 474610 0 0 3 0x14280 nfsidl nfsio 32970 237390 0 0 3 0x14280 nfsidl nfsio 32269 242967 1 0 3 0x100083 ttyin getty 37841 245446 52144 0 2 0x2 syz-executor.1 60457 333409 52144 0 3 0x82 nanoslp syz-executor.4 97352 258686 0 0 3 0x14200 bored sosplice 52144 265519 1950 0 3 0x2000082 thrsleep syz-fuzzer 52144 296442 1950 0 3 0x6000082 nanoslp syz-fuzzer 52144 364201 1950 0 3 0x6000082 wait syz-fuzzer 52144 24894 1950 0 3 0x6000082 wait syz-fuzzer 52144 122210 1950 0 3 0x6000082 thrsleep syz-fuzzer 52144 289521 1950 0 2 0x6000002 syz-fuzzer 52144 453542 1950 0 3 0x6000082 wait syz-fuzzer 52144 97157 1950 0 3 0x6000082 wait syz-fuzzer 52144 375302 1950 0 3 0x6000082 thrsleep syz-fuzzer 52144 372037 1950 0 2 0x6000002 syz-fuzzer 52144 91577 1950 0 3 0x6000082 thrsleep syz-fuzzer 52144 71571 1950 0 3 0x6000082 thrsleep syz-fuzzer 52144 16840 1950 0 3 0x6000082 wait syz-fuzzer 52144 83598 1950 0 3 0x6000082 wait syz-fuzzer 52144 197492 1950 0 3 0x6000082 wait syz-fuzzer 52144 247076 1950 0 2 0x6000002 syz-fuzzer 1950 149828 45394 0 3 0x10008a sigsusp ksh 45394 491934 62414 0 2 0x12 sshd 62414 518557 1 0 3 0x88 kqread sshd 22521 185735 76821 74 3 0x1100092 bpf pflogd 76821 484691 1 0 3 0x80 netio pflogd 57653 485096 59762 73 3 0x1100090 kqread syslogd 59762 135776 1 0 3 0x100082 netio syslogd 28269 355885 1 0 3 0x100080 kqread resolvd 51553 70546 83945 77 3 0x100092 kqread dhcpleased 51337 91064 83945 77 3 0x100092 kqread dhcpleased 83945 308700 1 0 3 0x80 kqread dhcpleased 15829 479371 0 0 3 0x14200 bored smr 88376 481361 0 0 2 0x14200 zerothread 43732 175564 0 0 3 0x14200 aiodoned aiodoned 38376 421243 0 0 3 0x14200 syncer update 9793 289436 0 0 3 0x14200 cleaner cleaner 46885 318372 0 0 3 0x14200 reaper reaper 73208 344158 0 0 3 0x14200 pgdaemon pagedaemon 78364 469432 0 0 3 0x14200 bored viomb 15344 160741 0 0 3 0x40014200 acpi0 acpi0 17769 130716 0 0 3 0x40014200 idle1 86108 130871 0 0 3 0x14200 bored softnet3 94478 508332 0 0 3 0x14200 bored softnet2 33369 330545 0 0 3 0x14200 bored softnet1 45591 523255 0 0 7 0x14200 softnet0 56045 8602 0 0 3 0x14200 bored systqmp 64599 446150 0 0 3 0x14200 bored systq *59515 327537 0 0 7 0x40014200 softclock 18618 25272 0 0 3 0x40014200 idle0 1 362027 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 37841 (syz-executor.1) thread 0xffff800021238800 (245446) exclusive rrwlock inode r = 0 (0xfffffd8069410a28) #0 witness_lock+0x447 #1 rw_enter+0x3c8 sys/kern/kern_rwlock.c:309 #2 rrw_enter+0x8c sys/kern/kern_rwlock.c:464 #3 VOP_LOCK+0x8b sys/kern/vfs_vops.c:518 #4 vn_lock+0x84 sys/kern/vfs_vnops.c:564 #5 vget+0x200 sys/kern/vfs_subr.c:676 #6 ufs_ihashget+0x121 sys/ufs/ufs/ufs_ihash.c:119 #7 ffs_vget+0x7c sys/ufs/ffs/ffs_vfsops.c:1314 #8 ufs_lookup+0x13ba sys/ufs/ufs/ufs_lookup.c:487 #9 VOP_LOOKUP+0x5c sys/kern/vfs_vops.c:85 #10 vfs_lookup+0x6e2 sys/kern/vfs_lookup.c:566 #11 namei+0x55a sys/kern/vfs_lookup.c:250 #12 dounlinkat+0x9d sys/kern/vfs_syscalls.c:1847 #13 syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] #13 syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 #14 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd80694103c8) #0 witness_lock+0x447 #1 rw_enter+0x3c8 sys/kern/kern_rwlock.c:309 #2 rrw_enter+0x8c sys/kern/kern_rwlock.c:464 #3 VOP_LOCK+0x8b sys/kern/vfs_vops.c:518 #4 vn_lock+0x84 sys/kern/vfs_vnops.c:564 #5 vget+0x200 sys/kern/vfs_subr.c:676 #6 cache_lookup+0x2b4 sys/kern/vfs_cache.c:222 #7 ufs_lookup+0x1ac sys/ufs/ufs/ufs_lookup.c:162 #8 VOP_LOOKUP+0x5c sys/kern/vfs_vops.c:85 #9 vfs_lookup+0x6e2 sys/kern/vfs_lookup.c:566 #10 namei+0x55a sys/kern/vfs_lookup.c:250 #11 dounlinkat+0x9d sys/kern/vfs_syscalls.c:1847 #12 syscall+0x5e2 mi_syscall sys/sys/syscall_mi.h:110 [inline] #12 syscall+0x5e2 sys/arch/amd64/amd64/trap.c:623 #13 Xsyscall+0x128 Process 59515 (softclock) thread 0xffff800021168aa0 (327537) exclusive rwlock netlock r = 0 (0xffffffff82b794a0) #0 witness_lock+0x447 #1 arptimer+0x26 sys/netinet/if_ether.c:132 #2 timeout_run+0xd0 sys/kern/kern_timeout.c:640 #3 softclock_thread+0x124 sys/kern/kern_timeout.c:763 #4 proc_trampoline+0x1c shared rwlock timeout r = 0 (0xffffffff82ba39d8) #0 witness_lock+0x447 #1 timeout_run+0xbb sys/kern/kern_timeout.c:636 #2 softclock_thread+0x124 sys/kern/kern_timeout.c:763 #3 proc_trampoline+0x1c exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82d45df0) #0 witness_lock+0x447 #1 __mp_acquire_count+0x48 sys/kern/kern_lock.c:227 #2 mi_switch+0x46b sys/kern/sched_bsd.c:470 #3 sleep_finish+0x19b sys/kern/kern_synch.c:414 #4 softclock_thread+0xd8 sys/kern/kern_timeout.c:758 #5 proc_trampoline+0x1c ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10226 6562K 7078K 78643K 31934 0 pcb 14 16K 18K 78643K 833 0 rtable 247 7K 7K 78643K 1181 0 pf 32 9K 10K 78643K 324 0 ifaddr 45 17K 18K 78643K 237 0 ifgroup 55 2K 2K 78643K 528 0 sysctl 3 1K 1K 78643K 3 0 counters 60 35K 36K 78643K 298 0 ioctlops 0 0K 4K 78643K 1950 0 iov 0 0K 24K 78643K 967 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1519 95K 95K 78643K 7506 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 139 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 2116 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 15 53K 81K 78643K 13806 0 sigio 0 0K 0K 78643K 2884 0 proc 70 91K 127K 78643K 1642 0 subproc 104 6K 7K 78643K 377 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 337 0 in_multi 99 7K 7K 78643K 420 0 ether_multi 1 0K 0K 78643K 17 0 mrt 1 0K 0K 78643K 7 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 229 1023K 1023K 78643K 229 0 exec 0 0K 1K 78643K 1973 0 pfkey data 0 0K 0K 78643K 7 0 tdb 3 0K 0K 78643K 3 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 8 62K 64K 78643K 10 0 UVM amap 417 95K 108K 78643K 139099 0 UVM aobj 131 6K 6K 78643K 136 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 283 0 NDP 12 0K 1K 78643K 189 0 temp 77 5920K 6048K 78643K 104077 0 kqueue 15 24K 28K 78643K 1345 0 SYN cache 2 16K 16K 78643K 2 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 22 0 0 1 0 1 1 0 8 0 rtpcb 120 287 0 284 1 0 1 1 0 8 0 rtentry 112 368 0 253 4 0 4 4 0 8 0 unpcb 144 6869 0 6854 101 98 3 10 0 8 2 syncache 304 111 0 111 23 23 0 1 0 8 0 tcpqe 32 260 0 260 15 15 0 1 0 8 0 tcpcb 808 8416 0 8396 163 158 5 17 0 8 1 arp 120 63 0 44 1 0 1 1 0 8 0 inpcb 368 12616 0 12590 178 169 9 16 0 8 4 nd6 136 103 0 75 1 0 1 1 0 8 0 pkpcb 40 147 0 147 8 8 0 1 0 8 0 kcovpl 48 29 0 21 1 0 1 1 0 8 0 ppxss 1256 23 0 23 8 8 0 1 0 8 0 pffrag 232 121 0 119 6 5 1 1 0 482 0 pffrnode 88 121 0 119 6 5 1 1 0 8 0 pffrent 40 492 0 490 8 7 1 1 0 8 0 pfosfp 40 1428 0 1005 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 367 0 346 1 0 1 1 0 8 0 pfstkey 128 367 0 346 2 1 1 2 0 8 0 pfstate 376 367 0 346 10 6 4 5 0 8 0 pfrule 1344 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 1470 0 985 33 2 31 31 0 8 0 art_table 32 1471 0 985 4 0 4 4 0 8 0 art_node 16 360 0 255 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 2114 0 2104 1 0 1 1 0 8 0 shmpl 112 133 0 5 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 19100 0 17572 96 0 96 96 0 8 0 ffsino 272 19100 0 17572 103 0 103 103 0 8 0 nchpl 144 37972 0 36316 64 0 64 64 0 8 0 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 123286 0 123286 6 5 1 2 0 8 1 percpumem 16 162 0 119 1 0 1 1 0 8 0 vmpool 696 230 0 230 13 13 0 1 0 8 0 kstatmem 264 262 0 238 2 0 2 2 0 8 0 scxspl 216 108768 0 108768 43 42 1 8 1 8 1 plimitpl 152 1254 0 1238 1 0 1 1 0 8 0 sigapl 424 14265 0 14197 10 2 8 8 0 8 0 futexpl 64 120011 0 120009 1 0 1 1 0 8 0 knotepl 120 667 0 0 9 0 9 9 0 8 0 kqueuepl 216 2617 0 2604 41 37 4 5 0 8 3 pipepl 320 15511 0 15479 201 194 7 18 0 8 4 fdescpl 496 14065 0 14037 6 2 4 5 0 8 0 filepl 152 103623 0 103355 246 230 16 24 0 8 5 lockfpl 104 3148 0 3145 6 5 1 2 0 8 0 lockfspl 48 1272 0 1269 1 0 1 1 0 8 0 sessionpl 144 46 0 29 1 0 1 1 0 8 0 pgrppl 48 295 0 278 1 0 1 1 0 8 0 ucredpl 104 9992 0 9978 1 0 1 1 0 8 0 zombiepl 144 14199 0 14197 1 0 1 1 0 8 0 processpl 1072 14265 0 14197 6 1 5 5 0 8 0 procpl 680 38900 0 38810 22 13 9 10 0 8 1 srpgc 96 2 0 2 1 1 0 1 0 8 0 sosppl 168 160 0 160 23 22 1 1 0 8 1 sockpl 488 19995 0 19951 450 436 14 34 0 8 6 mcl64k 65536 33 0 0 5 2 3 3 0 8 0 mcl16k 16384 37 0 0 4 1 3 3 0 8 0 mcl12k 12288 36 0 0 2 0 2 2 0 8 0 mcl9k 9216 19 0 0 2 0 2 2 0 8 0 mcl8k 8192 33 0 0 3 0 3 3 0 8 0 mcl4k 4096 93 0 0 8 5 3 6 0 8 0 mcl2k2 2112 13 0 0 1 0 1 1 0 8 0 mcl2k 2048 365 0 0 34 10 24 34 0 8 0 mtagpl 96 1036 0 0 17 0 17 17 0 8 0 mbufpl 256 1828 0 0 90 0 90 90 0 8 0 bufpl 288 25677 0 19350 453 0 453 453 0 8 0 anonpl 24 1386581 0 1370286 180 77 103 126 0 186 0 amapchunkpl 152 434403 0 433545 101 64 37 45 0 158 0 amappl16 200 28555 0 27931 171 138 33 48 0 8 0 amappl15 192 10 0 10 1 1 0 1 0 8 0 amappl14 184 235 0 217 2 1 1 2 0 8 0 amappl13 176 17 0 17 2 2 0 1 0 8 0 amappl12 168 15076 0 15044 4 1 3 3 0 8 0 amappl11 160 61 0 46 1 0 1 1 0 8 0 amappl10 152 78 0 66 1 0 1 1 0 8 0 amappl9 144 255 0 255 27 27 0 1 0 8 0 amappl8 136 606 0 477 6 1 5 5 0 8 0 amappl7 128 119 0 103 2 0 2 2 0 8 0 amappl6 120 475 0 447 1 0 1 1 0 8 0 amappl5 112 458 0 446 1 0 1 1 0 8 0 amappl4 104 957 0 906 2 0 2 2 0 8 0 amappl3 96 85125 0 85041 4 1 3 3 0 8 0 amappl2 88 14803 0 14727 3 1 2 3 0 8 0 amappl1 80 58883 0 58330 23 10 13 23 0 8 0 amappl 88 138028 0 137791 11 4 7 7 0 92 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma128 128 253 0 253 1 1 0 1 0 8 0 dma64 64 6 0 6 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 18 0 17 1 0 1 1 0 8 0 aobjpl 72 135 0 5 3 0 3 3 0 8 0 uaddrrnd 24 14295 0 14267 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 14295 0 14267 1 0 1 1 0 8 0 vmmpekpl 168 163658 0 163593 6 2 4 5 0 8 0 vmmpepl 168 834817 0 832203 317 190 127 129 0 357 7 vmsppl 464 14294 0 14267 5 1 4 5 0 8 0 rwobjpl 56 209032 0 201174 125 13 112 112 0 8 0 pdppl 4096 28598 0 28534 854 784 70 78 0 8 6 pvpl 32 3745672 0 3723398 504 321 183 337 0 265 0 pmappl 248 14294 0 14267 3 1 2 3 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 2067 0 1159 27 0 27 27 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827a1ffc) at panic+0x17b sys/kern/subr_prf.c:198 __assert(ffffffff82820837,ffffffff8281e421,2f6,ffffffff82770152) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd8075bd26a8) at arptfree+0x132 sys/netinet/if_ether.c:758 arptimer(ffffffff82d0bb70) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82d0bb70) at timeout_run+0xd0 sys/kern/kern_timeout.c:640 softclock_thread(ffff800021168aa0) at softclock_thread+0x124 sys/kern/kern_timeout.c:763 end trace frame: 0x0, count: -7 ddb{0}> machine ddbcpu 1