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 182348 83546 0 0x2 0 1 syz-executor.4 *509261 46057 0 0x14000 0x40000200 0K softclock db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827a639c) at panic+0x17b sys/kern/subr_prf.c:198 __assert(ffffffff82822a52,ffffffff8281e7ac,2f6,ffffffff827720c7) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd807a455a98) at arptfree+0x132 sys/netinet/if_ether.c:758 arptimer(ffffffff82cafcc0) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82cafcc0) 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(ffffffff827a639c) at panic+0x17b sys/kern/subr_prf.c:198 __assert(ffffffff82822a52,ffffffff8281e7ac,2f6,ffffffff827720c7) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd807a455a98) at arptfree+0x132 sys/netinet/if_ether.c:758 arptimer(ffffffff82cafcc0) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82cafcc0) 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 0xffff800021175530 rbx 0xffffffff82c1fba7 cpu_info_full_primary+0x2ba7 rdx 0 rcx 0xffff800021168aa0 rax 0xffffffff82c1eff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x2c27d0e73f04f056 r11 0x95b5ccaf3cfa541f r12 0xffffffff82c1f9a8 cpu_info_full_primary+0x29a8 r13 0 r14 0 r15 0x1 rip 0xffffffff81817f0c db_enter+0x1c cs 0x8 rflags 0x246 rsp 0xffff800021175520 ss 0x10 db_enter+0x1c: addq $0x8,%rsp ddb{0}> show proc PROC (softclock) tid=509261 pid=46057 tcnt=1 stat=onproc flags process=14000 proc=40000200 runpri=0, usrpri=51, slppri=0, nice=20 wchan=0x0, wmesg=, ps_single=0x0 forw=0xffffffffffffffff, list=0xffff800021168ff0,0xffff800021168808 process=0xffff8000ffffee10 user=0xffff800021170000, vmspace=0xffffffff82cfad88 estcpu=1, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 70186 31956 83546 0 3 0x80 nanoslp syz-executor.4 70186 474530 83546 0 3 0x4000080 netcon syz-executor.4 70186 487232 83546 0 3 0x4000080 fsleep syz-executor.4 70186 230098 83546 0 3 0x4000080 fsleep syz-executor.4 97959 196223 60409 0 3 0x82 piperd syz-executor.6 59380 289298 60409 0 3 0x82 piperd syz-executor.5 83546 182348 60409 0 7 0x2 syz-executor.4 45857 237554 60409 0 3 0x82 nanoslp syz-executor.1 21326 466476 0 0 3 0x14280 nfsidl nfsio 34830 452042 0 0 3 0x14280 nfsidl nfsio 29965 246467 0 0 3 0x14280 nfsidl nfsio 42441 423367 0 0 3 0x14280 nfsidl nfsio 89008 325220 0 0 3 0x14280 nfsidl nfsio 61772 390017 0 0 3 0x14280 nfsidl nfsio 30800 454025 0 0 3 0x14280 nfsidl nfsio 89799 73706 0 0 3 0x14280 nfsidl nfsio 95596 225632 0 0 3 0x14280 nfsidl nfsio 57955 490311 0 0 3 0x14280 nfsidl nfsio 89675 312476 0 0 3 0x14280 nfsidl nfsio 39145 25507 0 0 3 0x14280 nfsidl nfsio 51432 474978 0 0 3 0x14280 nfsidl nfsio 11518 379361 0 0 3 0x14280 nfsidl nfsio 71922 303736 0 0 3 0x14280 nfsidl nfsio 27336 478539 0 0 3 0x14280 nfsidl nfsio 37634 361248 0 0 3 0x14280 nfsidl nfsio 9432 213922 0 0 3 0x14280 nfsidl nfsio 61067 329766 0 0 3 0x14280 nfsidl nfsio 6647 130378 0 0 3 0x14280 nfsidl nfsio 66070 478110 60409 0 3 0x82 piperd syz-executor.3 49836 37421 0 0 3 0x14200 bored sosplice 27052 135515 60409 0 3 0x82 piperd syz-executor.7 76346 159720 60409 0 3 0x82 piperd syz-executor.2 60409 446021 58256 0 3 0x2000082 wait syz-fuzzer 60409 222753 58256 0 3 0x6000082 thrsleep syz-fuzzer 60409 134032 58256 0 3 0x6000082 wait syz-fuzzer 60409 510823 58256 0 3 0x6000082 thrsleep syz-fuzzer 60409 44337 58256 0 3 0x6000082 kqread syz-fuzzer 60409 270972 58256 0 3 0x6000082 wait syz-fuzzer 60409 137826 58256 0 3 0x6000082 thrsleep syz-fuzzer 60409 228521 58256 0 3 0x6000082 thrsleep syz-fuzzer 60409 294463 58256 0 3 0x6000082 thrsleep syz-fuzzer 60409 233522 58256 0 3 0x6000082 thrsleep syz-fuzzer 60409 1597 58256 0 3 0x6000082 thrsleep syz-fuzzer 60409 211633 58256 0 3 0x6000082 wait syz-fuzzer 60409 35511 58256 0 3 0x6000082 wait syz-fuzzer 60409 347687 58256 0 3 0x6000082 wait syz-fuzzer 60409 464297 58256 0 3 0x6000082 wait syz-fuzzer 60409 62438 58256 0 3 0x6000082 wait syz-fuzzer 58256 422844 4091 0 3 0x10008a sigsusp ksh 4091 129607 57496 0 3 0x9a kqread sshd 24832 228480 1 0 3 0x100083 ttyin getty 57496 384168 1 0 3 0x88 kqread sshd 8588 34380 23739 74 3 0x1100092 bpf pflogd 23739 251939 1 0 3 0x80 netio pflogd 73741 443441 30968 73 3 0x1100090 kqread syslogd 30968 477264 1 0 3 0x100082 netio syslogd 72035 24521 1 0 3 0x100080 kqread resolvd 28568 161327 13737 77 3 0x100092 kqread dhcpleased 21261 413400 13737 77 3 0x100092 kqread dhcpleased 13737 400550 1 0 3 0x80 kqread dhcpleased 45887 369971 0 0 3 0x14200 bored smr 91549 486884 0 0 3 0x14200 pgzero zerothread 68606 464325 0 0 3 0x14200 aiodoned aiodoned 29407 132852 0 0 3 0x14200 syncer update 70751 163561 0 0 3 0x14200 cleaner cleaner 3493 233532 0 0 3 0x14200 reaper reaper 35281 46126 0 0 3 0x14200 pgdaemon pagedaemon 65432 131469 0 0 3 0x14200 bored viomb 60713 176778 0 0 3 0x40014200 acpi0 acpi0 96810 244620 0 0 3 0x40014200 idle1 30475 257278 0 0 3 0x14200 bored softnet3 40749 252213 0 0 3 0x14200 bored softnet2 25340 290352 0 0 3 0x14200 bored softnet1 11635 460909 0 0 3 0x14200 bored softnet0 12998 165048 0 0 3 0x14200 bored systqmp 81089 12995 0 0 3 0x14200 bored systq *46057 509261 0 0 7 0x40014200 softclock 78338 280935 0 0 3 0x40014200 idle0 1 369262 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks CPU 1: exclusive mutex &cq->cq_mtx r = 0 (0xffff800020d59c38) #0 witness_lock+0x447 #1 mtx_enter_try+0x104 #2 mtx_enter+0x4f sys/kern/kern_lock.c:266 #3 clockintr_dispatch+0x2fd sys/kern/kern_clockintr.c:220 #4 lapic_clockintr+0x48 sys/arch/amd64/amd64/lapic.c:482 #5 Xresume_lapic_ltimer+0x2a #6 __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] #6 __mp_lock+0x122 sys/kern/kern_lock.c:147 #7 syscall+0x5cd mi_syscall sys/sys/syscall_mi.h:110 [inline] #7 syscall+0x5cd sys/arch/amd64/amd64/trap.c:623 #8 Xsyscall+0x128 Process 46057 (softclock) thread 0xffff800021168aa0 (509261) exclusive rwlock netlock r = 0 (0xffffffff82b875b0) #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 (0xffffffff82c180f8) #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 (0xffffffff82c92f70) #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 10227 6484K 7251K 78643K 20155 0 pcb 13 14K 16K 78643K 424 0 rtable 245 7K 7K 78643K 687 0 pf 35 10K 10K 78643K 136 0 ifaddr 46 16K 16K 78643K 111 0 ifgroup 60 2K 2K 78643K 204 0 sysctl 2 0K 0K 78643K 2 0 counters 62 36K 36K 78643K 144 0 ioctlops 0 0K 4K 78643K 1511 0 iov 0 0K 16K 78643K 301 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1548 97K 97K 78643K 4772 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 41 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 557 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 12 41K 73K 78643K 4229 0 sigio 0 0K 0K 78643K 47 0 proc 70 91K 115K 78643K 890 0 subproc 104 6K 6K 78643K 189 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 282 0 in_multi 99 7K 7K 78643K 222 0 ether_multi 1 0K 0K 78643K 5 0 mrt 1 0K 0K 78643K 4 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 241 1076K 1076K 78643K 241 0 exec 0 0K 1K 78643K 1132 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 371 92K 106K 78643K 44099 0 UVM aobj 131 4K 4K 78643K 131 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 111 0 NDP 13 0K 1K 78643K 82 0 temp 74 5920K 6048K 78643K 41661 0 kqueue 13 20K 26K 78643K 312 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 120 261 0 258 5 4 1 3 0 8 0 rtentry 112 224 0 110 4 0 4 4 0 8 0 unpcb 144 5350 0 5335 45 41 4 8 0 8 3 syncache 304 53 0 53 12 11 1 1 0 8 1 tcpqe 32 84 0 84 8 7 1 1 0 8 1 tcpcb 808 1618 0 1586 57 50 7 16 0 8 1 arp 120 31 0 12 1 0 1 1 0 8 0 inpcb 368 2854 0 2818 57 49 8 16 0 8 0 nd6 136 48 0 21 1 0 1 1 0 8 0 pkpcb 40 3 0 3 1 1 0 1 0 8 0 kcovpl 48 14 0 6 1 0 1 1 0 8 0 ppxss 1256 14 0 14 5 4 1 1 0 8 1 pffrag 232 47 0 45 1 0 1 1 0 482 0 pffrnode 88 47 0 45 1 0 1 1 0 8 0 pffrent 40 109 0 107 1 0 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 24 139 0 123 1 0 1 1 0 8 0 pfstkey 128 139 0 123 2 0 2 2 0 8 0 pfstate 376 139 0 123 6 2 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 256 745 0 280 32 2 30 30 0 8 0 art_table 32 746 0 280 4 0 4 4 0 8 0 art_node 16 183 0 79 1 0 1 1 0 8 0 sysvmsgpl 40 29 0 11 1 0 1 1 0 8 0 semapl 112 553 0 543 1 0 1 1 0 8 0 shmpl 112 128 0 0 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 7175 0 5706 93 0 93 93 0 8 0 ffsino 272 7175 0 5706 99 0 99 99 0 8 0 nchpl 144 12923 0 12421 63 40 23 63 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 46853 0 46853 6 5 1 2 0 8 1 percpumem 16 85 0 41 1 0 1 1 0 8 0 kstatmem 264 108 0 82 2 0 2 2 0 8 0 scxspl 216 44850 0 44850 16 15 1 8 1 8 1 plimitpl 152 635 0 619 1 0 1 1 0 8 0 sigapl 424 4560 0 4497 9 1 8 8 0 8 0 futexpl 64 35452 0 35450 4 3 1 1 0 8 0 knotepl 120 716 0 0 18 0 18 18 0 8 0 kqueuepl 216 910 0 900 17 16 1 5 0 8 0 pipepl 320 1060 0 1033 24 21 3 8 0 8 0 fdescpl 496 4522 0 4497 6 2 4 5 0 8 0 filepl 152 33295 0 33052 51 37 14 20 0 8 1 lockfpl 104 3104 0 3102 9 8 1 3 0 8 0 lockfspl 48 1431 0 1429 2 1 1 2 0 8 0 sessionpl 144 30 0 13 1 0 1 1 0 8 0 pgrppl 48 106 0 89 1 0 1 1 0 8 0 ucredpl 104 4704 0 4692 1 0 1 1 0 8 0 zombiepl 144 4499 0 4497 1 0 1 1 0 8 0 processpl 1072 4560 0 4497 5 0 5 5 0 8 0 procpl 680 12253 0 12172 12 3 9 9 0 8 0 sosppl 168 44 0 41 6 5 1 1 0 8 0 sockpl 488 8468 0 8414 188 172 16 30 0 8 6 mcl64k 65536 25 0 0 4 1 3 3 0 8 0 mcl16k 16384 11 0 0 2 0 2 2 0 8 0 mcl12k 12288 17 0 0 2 0 2 2 0 8 0 mcl9k 9216 15 0 0 2 0 2 2 0 8 0 mcl8k 8192 17 0 0 3 0 3 3 0 8 0 mcl4k 4096 17 0 0 3 0 3 3 0 8 0 mcl2k2 2112 8 0 0 1 0 1 1 0 8 0 mcl2k 2048 286 0 0 34 0 34 34 0 8 0 mtagpl 96 1151 0 0 28 0 28 28 0 8 0 mbufpl 256 3693 0 0 220 0 220 220 0 8 0 bufpl 288 10926 0 4599 453 0 453 453 0 8 0 anonpl 24 555974 0 541991 157 45 112 116 0 186 18 amapchunkpl 152 140568 0 139736 60 12 48 48 0 158 9 amappl16 200 11770 0 11366 50 19 31 35 0 8 8 amappl15 192 15 0 15 1 1 0 1 0 8 0 amappl14 184 191 0 176 2 1 1 2 0 8 0 amappl13 176 90 0 90 3 3 0 1 0 8 0 amappl12 168 5313 0 5285 3 1 2 2 0 8 0 amappl11 160 58 0 44 1 0 1 1 0 8 0 amappl10 152 37 0 23 1 0 1 1 0 8 0 amappl9 144 226 0 224 1 0 1 1 0 8 0 amappl8 136 439 0 327 4 0 4 4 0 8 0 amappl7 128 93 0 77 2 0 2 2 0 8 0 amappl6 120 309 0 282 3 2 1 3 0 8 0 amappl5 112 262 0 251 1 0 1 1 0 8 0 amappl4 104 693 0 646 3 1 2 3 0 8 0 amappl3 96 27702 0 27630 4 1 3 3 0 8 0 amappl2 88 4947 0 4880 3 1 2 3 0 8 0 amappl1 80 24998 0 24447 23 11 12 23 0 8 0 amappl 88 43429 0 43204 8 1 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 72 130 0 0 3 0 3 3 0 8 0 uaddrrnd 24 4522 0 4497 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 4522 0 4497 1 0 1 1 0 8 0 vmmpekpl 168 38917 0 38847 4 0 4 4 0 8 0 vmmpepl 168 286366 0 284134 224 102 122 131 0 357 11 vmsppl 464 4521 0 4497 5 1 4 5 0 8 0 rwobjpl 56 80564 0 72961 114 2 112 112 0 8 0 pdppl 4096 9052 0 8994 318 248 70 74 0 8 12 pvpl 32 1489998 0 1470196 420 218 202 365 0 265 29 pmappl 248 4521 0 4497 3 1 2 3 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 1405 0 364 31 0 31 31 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(ffffffff827a639c) at panic+0x17b sys/kern/subr_prf.c:198 __assert(ffffffff82822a52,ffffffff8281e7ac,2f6,ffffffff827720c7) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd807a455a98) at arptfree+0x132 sys/netinet/if_ether.c:758 arptimer(ffffffff82cafcc0) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82cafcc0) 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 Stopped at x86_ipi_db+0x1e: addq $0x8,%rsp x86_ipi_db(ffff800020d58ff0) at x86_ipi_db+0x1e sys/arch/amd64/amd64/db_interface.c:393 x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x35 sys/dev/kcov.c:164 __mp_lock(ffffffff82c92d68) at __mp_lock+0x133 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82c92d68) at __mp_lock+0x133 sys/kern/kern_lock.c:147 syscall(ffff8000226f3090) at syscall+0x5cd mi_syscall sys/sys/syscall_mi.h:110 [inline] syscall(ffff8000226f3090) at syscall+0x5cd sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x734e4f9267c0, count: 8 ddb{1}> trace x86_ipi_db(ffff800020d58ff0) at x86_ipi_db+0x1e sys/arch/amd64/amd64/db_interface.c:393 x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x35 sys/dev/kcov.c:164 __mp_lock(ffffffff82c92d68) at __mp_lock+0x133 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82c92d68) at __mp_lock+0x133 sys/kern/kern_lock.c:147 syscall(ffff8000226f3090) at syscall+0x5cd mi_syscall sys/sys/syscall_mi.h:110 [inline] syscall(ffff8000226f3090) at syscall+0x5cd sys/arch/amd64/amd64/trap.c:623 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x734e4f9267c0, count: -7