panic: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/setuid/kernel/sys/netinet/if_ether.c", line 758 Stopped at db_enter+0x1c: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 396970 95219 0 0x14000 0x200 1 reaper *256720 73816 0 0x14000 0x40000200 0K softclock db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827a7896) at panic+0x17b sys/kern/subr_prf.c:198 __assert(ffffffff82825c65,ffffffff82873deb,2f6,ffffffff82775655) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd80679b7ef0) at arptfree+0x132 sys/netinet/if_ether.c:758 arptimer(ffffffff82d39a90) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82d39a90) at timeout_run+0xd0 sys/kern/kern_timeout.c:665 softclock_thread(ffff800021169298) at softclock_thread+0x114 sys/kern/kern_timeout.c:809 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/setuid/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(ffffffff827a7896) at panic+0x17b sys/kern/subr_prf.c:198 __assert(ffffffff82825c65,ffffffff82873deb,2f6,ffffffff82775655) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd80679b7ef0) at arptfree+0x132 sys/netinet/if_ether.c:758 arptimer(ffffffff82d39a90) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82d39a90) at timeout_run+0xd0 sys/kern/kern_timeout.c:665 softclock_thread(ffff800021169298) at softclock_thread+0x114 sys/kern/kern_timeout.c:809 end trace frame: 0x0, count: -7 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800021175760 rbx 0xffffffff82b79ba7 cpu_info_full_primary+0x2ba7 rdx 0 rcx 0xffff800021169298 rax 0xffffffff82b78ff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0xa77b15df04a90f1c r11 0x5e48e2be36c3d271 r12 0xffffffff82b799a8 cpu_info_full_primary+0x29a8 r13 0 r14 0 r15 0x1 rip 0xffffffff82523a1c db_enter+0x1c cs 0x8 rflags 0x246 rsp 0xffff800021175750 ss 0x10 db_enter+0x1c: addq $0x8,%rsp ddb{0}> show proc PROC (softclock) tid=256720 pid=73816 tcnt=1 stat=onproc flags process=14000 proc=40000200 runpri=50, usrpri=51, slppri=0, nice=20 wchan=0x0, wmesg=, ps_single=0x0 forw=0xffffffffffffffff, list=0xffff800021169540,0xffff800021169000 process=0xffff8000ffffdd50 user=0xffff800021170000, vmspace=0xffffffff82cf8910 estcpu=1, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 71786 514843 51052 32767 3 0x3010 suspend syz-executor.3 71786 32822 51052 32767 2 0x4081010 syz-executor.3 3771 374188 40856 32767 2 0x10 syz-executor.7 3771 43188 40856 32767 3 0x4000090 fsleep syz-executor.7 5123 169541 40809 32767 2 0x10 syz-executor.5 5123 48742 40809 32767 3 0x4000090 kqread syz-executor.5 5123 463142 40809 32767 3 0x4000090 ttyout syz-executor.5 40856 157589 41843 32767 3 0x90 nanoslp syz-executor.7 41843 72726 11191 0 3 0x82 wait syz-executor.7 51052 162640 39584 32767 2 0x490 syz-executor.3 39584 151320 11191 0 3 0x82 wait syz-executor.3 81626 378770 45120 32767 3 0x90 piperd syz-executor.6 45120 313188 11191 0 3 0x82 wait syz-executor.6 27512 107080 664 32767 2 0x10 syz-executor.1 664 446271 11191 0 3 0x82 wait syz-executor.1 40809 56634 24248 32767 2 0x490 syz-executor.5 24248 24127 11191 0 3 0x82 wait syz-executor.5 82654 119204 58500 32767 2 0x10 syz-executor.2 58500 263925 11191 0 3 0x82 wait syz-executor.2 30664 90519 54059 32767 2 0x10 syz-executor.4 54059 130528 11191 0 3 0x82 wait syz-executor.4 86485 100217 11191 0 3 0x82 wait syz-executor.0 22718 506557 0 0 3 0x14200 bored sosplice 11191 179838 31151 0 3 0x2000082 wait syz-fuzzer 11191 498975 31151 0 3 0x6000082 nanoslp syz-fuzzer 11191 502924 31151 0 3 0x6000082 thrsleep syz-fuzzer 11191 371794 31151 0 3 0x6000082 thrsleep syz-fuzzer 11191 259629 31151 0 3 0x6000082 wait syz-fuzzer 11191 233068 31151 0 3 0x6000082 thrsleep syz-fuzzer 11191 11257 31151 0 3 0x6000082 wait syz-fuzzer 11191 248718 31151 0 3 0x6000082 thrsleep syz-fuzzer 11191 450400 31151 0 3 0x6000082 wait syz-fuzzer 11191 302520 31151 0 3 0x6000082 wait syz-fuzzer 11191 80788 31151 0 3 0x6000082 thrsleep syz-fuzzer 11191 494387 31151 0 3 0x6000082 kqread syz-fuzzer 11191 323041 31151 0 3 0x6000082 thrsleep syz-fuzzer 11191 308259 31151 0 3 0x6000082 wait syz-fuzzer 11191 521781 31151 0 3 0x6000082 wait syz-fuzzer 11191 273097 31151 0 3 0x6000082 wait syz-fuzzer 31151 138834 71278 0 3 0x10008a sigsusp ksh 71278 142754 64076 0 3 0x9a kqread sshd 12127 345075 1 0 3 0x100083 ttyin getty 64076 155558 1 0 3 0x88 kqread sshd 48349 180172 61730 73 3 0x1100090 kqread syslogd 61730 488658 1 0 3 0x100082 netio syslogd 90312 154080 1 0 3 0x100080 kqread resolvd 21474 507860 92259 77 3 0x100092 kqread dhcpleased 34936 125362 92259 77 3 0x100092 kqread dhcpleased 92259 322519 1 0 3 0x80 kqread dhcpleased 45269 455339 0 0 3 0x14200 bored smr 62759 124182 0 0 3 0x14200 pgzero zerothread 74988 136170 0 0 3 0x14200 aiodoned aiodoned 12221 242070 0 0 3 0x14200 syncer update 75470 300962 0 0 3 0x14200 cleaner cleaner 95219 396970 0 0 7 0x14200 reaper 75198 408148 0 0 3 0x14200 pgdaemon pagedaemon 55730 16670 0 0 3 0x14200 bored viomb 15594 186960 0 0 3 0x40014200 acpi0 acpi0 66340 203936 0 0 3 0x40014200 idle1 8424 486277 0 0 3 0x14200 bored softnet3 27708 307024 0 0 3 0x14200 bored softnet2 29119 183752 0 0 3 0x14200 bored softnet1 88710 176102 0 0 3 0x14200 bored softnet0 21803 270975 0 0 3 0x14200 bored systqmp 12062 239973 0 0 3 0x14200 bored systq 62350 84897 0 0 3 0x14200 tmoslp softclockmp *73816 256720 0 0 7 0x40014200 softclock 97638 467917 0 0 3 0x40014200 idle0 1 55878 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 73816 (softclock) thread 0xffff800021169298 (256720) exclusive rwlock netlock r = 0 (0xffffffff82b717b0) #0 witness_lock+0x447 #1 arptimer+0x26 sys/netinet/if_ether.c:132 #2 timeout_run+0xd0 sys/kern/kern_timeout.c:665 #3 softclock_thread+0x114 sys/kern/kern_timeout.c:809 #4 proc_trampoline+0x10 shared rwlock timeout r = 0 (0xffffffff82c4aed8) #0 witness_lock+0x447 #1 timeout_run+0xbb sys/kern/kern_timeout.c:661 #2 softclock_thread+0x114 sys/kern/kern_timeout.c:809 #3 proc_trampoline+0x10 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82c58ae8) #0 witness_lock+0x447 #1 __mp_acquire_count+0x48 sys/kern/kern_lock.c:227 #2 mi_switch+0x46d sys/kern/sched_bsd.c:470 #3 sleep_finish+0x19b sys/kern/kern_synch.c:414 #4 msleep+0xea sys/kern/kern_synch.c:249 #5 softclock_thread+0xd0 sys/kern/kern_timeout.c:805 #6 proc_trampoline+0x10 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10223 6414K 6420K 78643K 11444 0 pcb 13 12K 14K 78643K 17 0 rtable 254 7K 7K 78643K 4035 0 pf 29 8K 8K 78643K 123 0 ifaddr 44 15K 16K 78643K 238 0 ifgroup 50 2K 2K 78643K 238 0 sysctl 4 1K 1K 78643K 4 0 counters 60 35K 35K 78643K 154 0 ioctlops 0 0K 2K 78643K 337 0 iov 0 0K 24K 78643K 4403 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1279 80K 80K 78643K 21493 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 542 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 5600 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 21 77K 121K 78643K 39714 0 sigio 0 0K 0K 78643K 907 0 proc 56 78K 103K 78643K 3406 0 subproc 104 6K 6K 78643K 715 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 1880 0 in_multi 99 7K 7K 78643K 971 0 ether_multi 1 0K 0K 78643K 88 0 mrt 1 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 277 1235K 1235K 78643K 277 0 exec 0 0K 1K 78643K 5397 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 555 97K 113K 78643K 392219 0 UVM aobj 131 4K 4K 78643K 144 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 1004 0 NDP 11 0K 2K 78643K 168 0 temp 74 5924K 6052K 78643K 97519 0 kqueue 13 18K 32K 78643K 3192 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 2925 0 2922 39 38 1 3 0 8 0 rtentry 112 694 0 574 4 0 4 4 0 8 0 unpcb 144 38268 0 38253 365 359 6 10 0 8 4 syncache 304 514 0 514 74 73 1 1 0 8 1 sackhl 24 2 0 2 2 2 0 1 0 8 0 tcpqe 32 463 0 463 67 66 1 1 0 8 1 tcpcb 808 15808 0 15741 353 343 10 17 0 8 0 arp 120 118 0 99 1 0 1 1 0 8 0 ipq 40 84 0 83 23 22 1 1 0 8 0 ipqe 40 567 0 566 23 22 1 1 0 8 0 inpcb 368 27633 0 27563 440 432 8 17 0 8 0 nd6 136 225 0 192 5 3 2 2 0 8 0 kcovpl 48 55 0 47 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 2724 0 2250 36 5 31 32 0 8 0 art_table 32 2725 0 2250 6 2 4 5 0 8 0 art_node 16 693 0 583 1 0 1 1 0 8 0 semapl 112 5598 0 5588 1 0 1 1 0 8 0 shmpl 112 141 0 13 5 1 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 66800 0 65332 92 0 92 92 0 8 0 ffsino 272 66800 0 65332 98 0 98 98 0 8 0 nchpl 144 120700 0 119047 63 0 63 63 0 8 0 uvmvnodes 80 7973 0 0 163 0 163 163 0 8 0 vnodes 216 7973 0 0 443 0 443 443 0 8 0 namei 1024 440043 0 440043 11 10 1 2 0 8 1 percpumem 16 90 0 47 1 0 1 1 0 8 0 kstatmem 264 116 0 94 2 0 2 2 0 8 0 scxspl 216 356714 0 356714 132 129 3 8 1 8 3 plimitpl 152 7129 0 7106 66 64 2 2 0 8 1 sigapl 424 39916 0 39865 7 0 7 7 0 8 0 futexpl 64 356341 0 356340 15 14 1 1 0 8 0 knotepl 120 2593 0 0 20 3 17 17 0 8 0 kqueuepl 216 8715 0 8705 157 154 3 8 0 8 2 pipepl 320 10385 0 10357 265 259 6 13 0 8 3 fdescpl 496 39897 0 39865 7 2 5 6 0 8 0 filepl 152 316433 0 316189 541 525 16 24 0 8 5 lockfpl 104 5657 0 5655 3 2 1 2 0 8 0 lockfspl 48 1592 0 1590 1 0 1 1 0 8 0 sessionpl 144 70 0 54 1 0 1 1 0 8 0 pgrppl 48 4246 0 4230 1 0 1 1 0 8 0 ucredpl 104 106515 0 106497 1 0 1 1 0 8 0 zombiepl 144 39867 0 39865 1 0 1 1 0 8 0 processpl 1072 39916 0 39865 5 1 4 5 0 8 0 procpl 680 111676 0 111605 84 76 8 9 0 8 1 sosppl 168 689 0 683 52 51 1 1 0 8 0 sockpl 488 70613 0 70525 1372 1344 28 38 0 8 14 mcl64k 65536 114 0 0 3 0 3 3 0 8 0 mcl16k 16384 114 0 0 5 2 3 3 0 8 0 mcl12k 12288 81 0 0 2 0 2 2 0 8 0 mcl9k 9216 43 0 0 2 0 2 2 0 8 0 mcl8k 8192 114 0 0 8 5 3 3 0 8 0 mcl4k 4096 260 0 0 14 11 3 10 0 8 0 mcl2k2 2112 17 0 0 2 0 2 2 0 8 0 mcl2k 2048 1052 0 0 41 27 14 34 0 8 0 mtagpl 96 19 0 0 1 0 1 1 0 8 0 mbufpl 256 4001 0 0 113 3 110 110 0 8 0 bufpl 288 70214 0 62239 570 0 570 570 0 8 0 anonpl 24 3788164 0 3772302 206 105 101 105 0 186 0 amapchunkpl 152 1264072 0 1263226 386 347 39 50 0 158 1 amappl16 200 71722 0 71185 364 335 29 30 0 8 0 amappl15 192 37 0 37 8 8 0 1 0 8 0 amappl14 184 345 0 331 2 1 1 2 0 8 0 amappl13 176 58 0 57 1 0 1 1 0 8 0 amappl12 168 41257 0 41220 3 1 2 3 0 8 0 amappl11 160 77 0 66 1 0 1 1 0 8 0 amappl10 152 108 0 97 1 0 1 1 0 8 0 amappl9 144 3604 0 3604 50 49 1 1 0 8 1 amappl8 136 3855 0 3516 12 0 12 12 0 8 0 amappl7 128 1122 0 1096 2 0 2 2 0 8 0 amappl6 120 1606 0 1588 1 0 1 1 0 8 0 amappl5 112 1550 0 1542 1 0 1 1 0 8 0 amappl4 104 3284 0 3250 3 1 2 2 0 8 0 amappl3 96 241259 0 241173 21 18 3 4 0 8 0 amappl2 88 42245 0 42164 15 13 2 3 0 8 0 amappl1 80 145267 0 144750 22 10 12 22 0 8 0 amappl 88 389607 0 389363 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 72 143 0 13 3 0 3 3 0 8 0 uaddrrnd 24 39897 0 39865 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 39897 0 39865 1 0 1 1 0 8 0 vmmpekpl 168 315145 0 315074 4 0 4 4 0 8 0 vmmpepl 168 2292724 0 2289965 431 299 132 138 0 357 4 vmsppl 464 39896 0 39865 7 2 5 6 0 8 0 rwobjpl 56 556639 0 546715 180 39 141 141 0 8 0 pdppl 4096 79802 0 79730 1252 1172 80 94 0 8 8 pvpl 32 11392475 0 11370250 1051 859 192 353 0 265 8 pmappl 248 39896 0 39865 4 1 3 3 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 3127 0 2088 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(ffffffff827a7896) at panic+0x17b sys/kern/subr_prf.c:198 __assert(ffffffff82825c65,ffffffff82873deb,2f6,ffffffff82775655) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd80679b7ef0) at arptfree+0x132 sys/netinet/if_ether.c:758 arptimer(ffffffff82d39a90) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82d39a90) at timeout_run+0xd0 sys/kern/kern_timeout.c:665 softclock_thread(ffff800021169298) at softclock_thread+0x114 sys/kern/kern_timeout.c:809 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 __mp_lock(ffffffff82c588e0) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82c588e0) at __mp_lock+0x122 sys/kern/kern_lock.c:147 reaper(ffff8000211b32a0) at reaper+0x160 sys/kern/kern_exit.c:446 end trace frame: 0x0, count: 10 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 __mp_lock(ffffffff82c588e0) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82c588e0) at __mp_lock+0x122 sys/kern/kern_lock.c:147 reaper(ffff8000211b32a0) at reaper+0x160 sys/kern/kern_exit.c:446 end trace frame: 0x0, count: -5