login: panic: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/main/kernel/sys/netinet/if_ether.c", line 776 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *341977 79429 0 0x14000 0x40000200 0 softclock db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8272bf81) at panic+0x161 sys/kern/subr_prf.c:198 __assert(ffffffff827a37f0,ffffffff827c4b1c,308,ffffffff826f61bb) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd807acef9a8) at arptfree+0x12d sys/netinet/if_ether.c:776 arptimer(ffffffff82beb748) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82beb748) at timeout_run+0x8b sys/kern/kern_timeout.c:641 softclock_thread(ffff8000ffffed98) at softclock_thread+0xf4 sys/kern/kern_timeout.c:765 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> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic *cpu0: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/main/kernel/sys/netinet/if_ether.c", line 776 ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8272bf81) at panic+0x161 sys/kern/subr_prf.c:198 __assert(ffffffff827a37f0,ffffffff827c4b1c,308,ffffffff826f61bb) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd807acef9a8) at arptfree+0x12d sys/netinet/if_ether.c:776 arptimer(ffffffff82beb748) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82beb748) at timeout_run+0x8b sys/kern/kern_timeout.c:641 softclock_thread(ffff8000ffffed98) at softclock_thread+0xf4 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: -7 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff8000216049b0 rbx 0 rdx 0 rcx 0 rax 0xffff8000ffffed98 r8 0x101010101010101 r9 0x8080808080808080 r10 0xcbf3b84af2ddaa19 r11 0x2cdfb9b49446073f r12 0 r13 0xfffffd806efe6898 r14 0 r15 0x1 rip 0xffffffff823c2a78 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000216049a0 ss 0 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=341977 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000fffff050,0xffff8000ffffe010 process=0xffff8000ffffc3f0 user=0xffff8000215ff000, vmspace=0xffffffff82c0dfc8 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 32251 461662 38544 0 2 0 syz-executor.2 33903 77718 91389 0 2 0 syz-executor.5 11290 337936 78988 0 2 0 syz-executor.1 11290 136407 78988 0 3 0x4000080 fsleep syz-executor.1 96454 358922 35413 0 2 0 syz-executor.7 96454 281555 35413 0 3 0x4000080 fsleep syz-executor.7 96454 337068 35413 0 3 0x4000080 fsleep syz-executor.7 29913 393317 91147 0 2 0 syz-executor.6 29913 106003 91147 0 3 0x4000080 fsleep syz-executor.6 29913 522392 91147 0 3 0x4000080 fsleep syz-executor.6 4870 174218 1 0 3 0x100083 ttyin getty 91147 61690 127 0 2 0x482 syz-executor.6 78988 363546 127 0 2 0x482 syz-executor.1 87147 252991 127 0 2 0x2 syz-executor.3 38544 110819 127 0 2 0x2 syz-executor.2 91389 489860 127 0 2 0x482 syz-executor.5 35413 445115 127 0 2 0x482 syz-executor.7 54942 114301 127 0 2 0x2 syz-executor.4 73857 486831 0 0 3 0x14280 nfsidl nfsio 32139 68925 0 0 3 0x14280 nfsidl nfsio 52118 468150 0 0 3 0x14280 nfsidl nfsio 87120 3183 0 0 3 0x14280 nfsidl nfsio 76177 136315 0 0 3 0x14280 nfsidl nfsio 9635 484801 0 0 3 0x14280 nfsidl nfsio 61683 342321 0 0 3 0x14280 nfsidl nfsio 22646 375160 0 0 3 0x14280 nfsidl nfsio 89086 523742 0 0 3 0x14280 nfsidl nfsio 64300 189678 0 0 3 0x14280 nfsidl nfsio 28502 483742 0 0 3 0x14280 nfsidl nfsio 70137 413595 0 0 3 0x14280 nfsidl nfsio 85430 491399 0 0 3 0x14280 nfsidl nfsio 81970 209161 0 0 3 0x14280 nfsidl nfsio 71263 279357 0 0 3 0x14280 nfsidl nfsio 51144 323074 0 0 3 0x14280 nfsidl nfsio 53062 137847 0 0 3 0x14280 nfsidl nfsio 20394 384816 0 0 3 0x14280 nfsidl nfsio 37842 81679 0 0 3 0x14280 nfsidl nfsio 98768 308338 0 0 3 0x14280 nfsidl nfsio 26073 247084 0 0 3 0x14200 bored sosplice 127 329909 96342 0 3 0x82 wait syz-fuzzer 127 162556 96342 0 2 0x4000482 syz-fuzzer 127 469390 96342 0 3 0x4000082 wait syz-fuzzer 127 1517 96342 0 3 0x4000082 wait syz-fuzzer 127 305011 96342 0 3 0x4000082 thrsleep syz-fuzzer 127 228561 96342 0 3 0x4000082 wait syz-fuzzer 127 12060 96342 0 3 0x4000082 thrsleep syz-fuzzer 127 287792 96342 0 3 0x4000082 thrsleep syz-fuzzer 127 512381 96342 0 3 0x4000082 wait syz-fuzzer 127 407408 96342 0 3 0x4000082 thrsleep syz-fuzzer 127 351472 96342 0 3 0x4000082 thrsleep syz-fuzzer 127 240000 96342 0 2 0x4000002 syz-fuzzer 127 6619 96342 0 3 0x4000082 wait syz-fuzzer 127 23740 96342 0 3 0x4000082 wait syz-fuzzer 96342 250758 83292 0 3 0x10008a sigsusp ksh 83292 49244 20533 0 3 0x9a kqread sshd 20533 110077 1 0 3 0x88 kqread sshd 60984 465648 41026 73 3 0x1100090 kqread syslogd 41026 447457 1 0 3 0x100082 netio syslogd 82117 421669 1 0 3 0x100080 kqread resolvd 14500 297986 96292 77 3 0x100092 kqread dhcpleased 38662 226309 96292 77 3 0x100092 kqread dhcpleased 96292 405486 1 0 3 0x80 kqread dhcpleased 21526 391263 0 0 2 0x14200 smr 61218 358931 0 0 2 0x14200 zerothread 15299 1081 0 0 3 0x14200 aiodoned aiodoned 36068 219583 0 0 3 0x14200 syncer update 60728 6348 0 0 3 0x14200 cleaner cleaner 90404 288569 0 0 3 0x14200 reaper reaper 35466 310362 0 0 3 0x14200 pgdaemon pagedaemon 6026 136737 0 0 3 0x14200 bored viomb 69399 279925 0 0 3 0x40014200 acpi0 acpi0 38891 495985 0 0 3 0x14200 bored softnet 80243 441543 0 0 3 0x14200 bored softnet 77198 319184 0 0 3 0x14200 bored softnet 26282 489263 0 0 3 0x14200 bored softnet 23671 90174 0 0 3 0x14200 bored systqmp 8492 376083 0 0 2 0x14200 systq *79429 341977 0 0 7 0x40014200 softclock 79427 256427 0 0 3 0x40014200 idle0 1 191628 0 0 3 0x82 wait init 0 0 -1 0 2 0x10200 swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10223 6493K 7145K 78643K 35628 0 pcb 15 18K 21K 78643K 1541 0 rtable 173 9K 9K 78643K 2580 0 ifaddr 74 22K 25K 78643K 805 0 sysctl 3 1K 1K 78643K 3 0 counters 26 17K 17K 78643K 317 0 ioctlops 0 0K 4K 78643K 1816 0 iov 0 0K 28K 78643K 1205 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1456 91K 91K 78643K 9864 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 94 0 VM map 2 1K 1K 78643K 2 0 sem 12 1K 1K 78643K 12 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 15 53K 69K 78643K 8834 0 sigio 0 0K 0K 78643K 311 0 proc 60 59K 75K 78643K 1975 0 subproc 104 6K 6K 78643K 637 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 544 0 in_multi 63 4K 6K 78643K 1001 0 ether_multi 1 0K 0K 78643K 60 0 mrt 1 0K 0K 78643K 38 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 211 943K 943K 78643K 211 0 exec 0 0K 1K 78643K 1987 0 pfkey data 0 0K 0K 78643K 8 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 308 86K 102K 78643K 57518 0 UVM aobj 131 4K 4K 78643K 134 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 309 0 NDP 12 0K 1K 78643K 292 0 temp 130 5770K 39562K 78643K 122015 0 kqueue 13 20K 26K 78643K 772 0 SYN cache 2 16K 16K 78643K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 794 0 791 14 13 1 3 0 8 0 rtentry 112 919 0 849 4 0 4 4 0 8 0 unpcb 144 8883 0 8869 77 76 1 8 0 8 0 syncache 296 41 0 41 9 9 0 1 0 8 0 tcpqe 32 204 0 204 6 6 0 1 0 8 0 tcpcb 776 3203 0 3198 95 93 2 14 0 8 1 arp 88 110 0 97 1 0 1 1 0 8 0 ipq 40 3 0 3 2 2 0 1 0 8 0 ipqe 40 6 0 6 2 2 0 1 0 8 0 inpcb 336 9863 0 9853 131 129 2 18 0 8 1 nd6 48 197 0 182 1 0 1 1 0 8 0 pkpcb 40 30 0 30 9 9 0 1 0 8 0 kcovpl 48 49 0 41 1 0 1 1 0 8 0 mppekey 1024 80 0 80 6 5 1 1 0 8 1 ppxss 1160 177 0 177 14 13 1 1 0 8 1 pppxif 1360 43 0 43 9 9 0 1 0 8 0 pfstscr 40 79 0 74 1 0 1 1 0 8 0 pfanchor 1280 848 2 336 49 6 43 43 0 8 0 pfstitem 24 16 0 6 1 0 1 1 0 8 0 pfstkey 128 158 0 153 1 0 1 1 0 8 0 pfstate 352 79 0 74 1 0 1 1 0 8 0 rttmr 136 9 0 9 3 3 0 1 0 8 0 art_heap8 4096 2 0 1 2 1 1 2 0 8 0 art_heap4 256 4515 0 4226 51 31 20 30 0 8 1 art_table 32 4517 0 4227 6 3 3 4 0 8 0 art_node 16 916 0 856 1 0 1 1 0 8 0 sysvmsgpl 40 71 0 69 1 0 1 1 0 8 0 semupl 112 2 0 2 1 1 0 1 0 8 0 semapl 112 10 0 0 1 0 1 1 0 8 0 shmpl 112 131 0 3 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 14730 0 13285 92 0 92 92 0 8 0 ffsino 240 14730 0 13285 86 0 86 86 0 8 0 nchpl 144 27670 0 26044 63 1 62 63 0 8 0 rtmask 32 3 0 3 1 1 0 1 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 109586 0 109586 4 3 1 3 0 8 1 vmpool 664 110 0 110 10 10 0 1 0 8 0 kstatmem 264 312 0 288 2 0 2 2 0 8 0 scsiplug 72 5 0 5 1 1 0 1 0 8 0 scxspl 216 73901 0 73901 23 22 1 8 0 8 1 plimitpl 152 1180 0 1164 1 0 1 1 0 8 0 sigapl 424 9288 0 9225 8 0 8 8 0 8 0 futexpl 64 94887 0 94882 1 0 1 1 0 8 0 knotepl 120 129919 0 129801 72 67 5 14 0 8 1 kqueuepl 184 1853 0 1844 23 21 2 4 0 8 1 pipepl 288 3177 0 3150 61 58 3 7 0 8 0 fdescpl 432 9030 0 9004 4 0 4 4 0 8 0 filepl 120 82118 0 81874 120 109 11 17 0 8 2 lockfpl 104 3106 0 3104 3 2 1 2 0 8 0 lockfspl 48 1107 0 1105 1 0 1 1 0 8 0 sessionpl 144 69 0 53 1 0 1 1 0 8 0 pgrppl 48 133 0 117 1 0 1 1 0 8 0 ucredpl 104 8475 0 8460 1 0 1 1 0 8 0 zombiepl 144 9226 0 9225 1 0 1 1 0 8 0 processpl 1008 9288 0 9225 10 1 9 9 0 8 0 procpl 696 22436 0 22355 16 7 9 10 0 8 0 sosppl 168 65 0 65 15 15 0 1 0 8 0 sockpl 456 19618 0 19591 407 401 6 32 0 8 2 mcl64k 65536 351 0 351 25 24 1 1 0 8 1 mcl16k 16384 138 0 138 19 19 0 1 0 8 0 mcl12k 12288 313 0 313 18 17 1 1 0 8 1 mcl9k 9216 109 0 109 18 18 0 1 0 8 0 mcl8k 8192 536 0 536 23 22 1 1 0 8 1 mcl4k 4096 1008 0 1008 15 14 1 2 0 8 1 mcl2k2 2112 63 0 63 21 21 0 1 0 8 0 mcl2k 2048 91952 0 91884 77 67 10 34 0 8 0 mtagpl 96 3362 0 3083 28 14 14 21 0 8 0 mbufpl 256 222474 0 222002 433 373 60 119 0 8 0 bufpl 288 16949 0 10555 458 1 457 458 0 8 0 anonpl 24 1727600 0 1710201 228 110 118 135 0 188 0 amapchunkpl 152 168131 0 167441 89 49 40 41 0 158 8 amappl16 200 17372 0 16803 86 53 33 44 0 8 0 amappl15 192 70 0 69 1 0 1 1 0 8 0 amappl14 184 351 0 338 2 0 2 2 0 8 0 amappl13 176 9 0 9 2 2 0 1 0 8 0 amappl12 168 891 0 890 1 0 1 1 0 8 0 amappl11 160 48 0 37 1 0 1 1 0 8 0 amappl10 152 77 0 65 1 0 1 1 0 8 0 amappl9 144 990 0 988 1 0 1 1 0 8 0 amappl8 136 400 0 324 3 0 3 3 0 8 0 amappl7 128 244 0 221 2 0 2 2 0 8 0 amappl6 120 401 0 384 2 1 1 2 0 8 0 amappl5 112 356 0 350 1 0 1 1 0 8 0 amappl4 104 1054 0 1029 2 1 1 2 0 8 0 amappl3 96 25118 0 25066 2 0 2 2 0 8 0 amappl2 88 9806 0 9735 3 1 2 3 0 8 0 amappl1 80 202189 0 201503 26 10 16 26 0 8 0 amappl 88 56337 0 56167 5 0 5 5 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 72 133 0 3 3 0 3 3 0 8 0 uaddrrnd 24 9140 0 9114 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 9140 0 9114 1 0 1 1 0 8 0 vmmpekpl 168 74026 0 73966 4 0 4 4 0 8 0 vmmpepl 168 832040 0 829413 296 153 143 152 0 357 9 vmsppl 344 9139 0 9114 3 0 3 3 0 8 0 rwobjpl 24 215274 0 207553 52 4 48 49 0 8 0 pdppl 4096 18286 0 18228 605 541 64 66 0 8 6 pvpl 32 3398064 0 3375449 503 298 205 333 0 265 6 pmappl 216 9139 0 9114 2 0 2 2 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 2103 0 1299 26 0 26 26 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8272bf81) at panic+0x161 sys/kern/subr_prf.c:198 __assert(ffffffff827a37f0,ffffffff827c4b1c,308,ffffffff826f61bb) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd807acef9a8) at arptfree+0x12d sys/netinet/if_ether.c:776 arptimer(ffffffff82beb748) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82beb748) at timeout_run+0x8b sys/kern/kern_timeout.c:641 softclock_thread(ffff8000ffffed98) at softclock_thread+0xf4 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: -7 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8272bf81) at panic+0x161 sys/kern/subr_prf.c:198 __assert(ffffffff827a37f0,ffffffff827c4b1c,308,ffffffff826f61bb) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd807acef9a8) at arptfree+0x12d sys/netinet/if_ether.c:776 arptimer(ffffffff82beb748) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82beb748) at timeout_run+0x8b sys/kern/kern_timeout.c:641 softclock_thread(ffff8000ffffed98) at softclock_thread+0xf4 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: -7