panic: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/setuid/kernel/sys/netinet/if_ether.c", line 776 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 398230 42834 32767 0x10 0 1 syz-executor.7 * 57393 51390 0 0x14000 0x40000200 0K softclock db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff825a8139) at panic+0x177 sys/kern/subr_prf.c:198 __assert(ffffffff82621196,ffffffff8266995b,308,ffffffff825797f0) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd8069d51d38) at arptfree+0x12e sys/netinet/if_ether.c:776 arptimer(ffffffff82b1dbe8) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82b1dbe8) at timeout_run+0xcc sys/kern/kern_timeout.c:641 softclock_thread(ffff8000211e9500) at softclock_thread+0x134 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{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 776 ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff825a8139) at panic+0x177 sys/kern/subr_prf.c:198 __assert(ffffffff82621196,ffffffff8266995b,308,ffffffff825797f0) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd8069d51d38) at arptfree+0x12e sys/netinet/if_ether.c:776 arptimer(ffffffff82b1dbe8) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82b1dbe8) at timeout_run+0xcc sys/kern/kern_timeout.c:641 softclock_thread(ffff8000211e9500) at softclock_thread+0x134 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: -7 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff8000211f52e0 rbx 0xffffffff829c5b8f cpu_info_full_primary+0x2b8f rdx 0 rcx 0 rax 0xffff8000211e9500 r8 0x101010101010101 r9 0x8080808080808080 r10 0x1f849230a1514d8c r11 0xfbeacb3160d1139c r12 0xffffffff829c5990 cpu_info_full_primary+0x2990 r13 0 r14 0 r15 0x1 rip 0xffffffff81293b58 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000211f52d0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (softclock) pid=57393 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000211e97a0,0xffff8000211e8fd0 process=0xffff8000ffffe180 user=0xffff8000211f0000, vmspace=0xffffffff82a10800 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 60765 300551 14521 32767 3 0x90 nanoslp syz-executor.2 60765 231219 14521 32767 3 0x4000090 ttyout syz-executor.2 60765 465051 14521 32767 3 0x4000090 fsleep syz-executor.2 60765 375438 14521 32767 3 0x4000090 ttyout syz-executor.2 63271 135627 42834 32767 3 0x90 nanoslp syz-executor.7 63271 454003 42834 32767 3 0x4000090 kqpoll syz-executor.7 63271 87271 42834 32767 3 0x4000090 fsleep syz-executor.7 63271 98300 42834 32767 3 0x4000090 kqpoll syz-executor.7 42834 398230 87196 32767 7 0x10 syz-executor.7 87196 112516 162 0 3 0x82 wait syz-executor.7 10746 271648 67727 32767 3 0x90 piperd syz-executor.6 67727 492462 162 0 3 0x82 wait syz-executor.6 14521 406609 55729 32767 3 0x90 nanoslp syz-executor.2 55729 266953 162 0 3 0x82 wait syz-executor.2 42092 129743 99055 32767 3 0x90 piperd syz-executor.3 99055 306540 162 0 3 0x82 wait syz-executor.3 2691 247983 162 0 3 0x82 wait syz-executor.0 14425 436498 0 0 3 0x14200 bored sosplice 83778 317264 21934 32767 3 0x90 piperd syz-executor.5 21934 274880 162 0 3 0x82 wait syz-executor.5 45952 478879 56249 0 3 0x100082 netio arp 3617 3918 48475 32767 3 0x90 piperd syz-executor.4 56249 204655 35067 0 3 0x10008a sigsusp sh 48475 144847 162 0 3 0x82 wait syz-executor.4 81199 143293 21827 32767 3 0x90 piperd syz-executor.1 35067 454976 1 0 3 0x80 wait syz-executor.2 21827 387596 162 0 3 0x82 wait syz-executor.1 162 175899 47233 0 3 0x82 wait syz-fuzzer 162 296972 47233 0 3 0x4000082 thrsleep syz-fuzzer 162 194704 47233 0 3 0x4000082 thrsleep syz-fuzzer 162 522349 47233 0 3 0x4000082 wait syz-fuzzer 162 34976 47233 0 3 0x4000082 thrsleep syz-fuzzer 162 154734 47233 0 3 0x4000082 wait syz-fuzzer 162 372159 47233 0 3 0x4000082 thrsleep syz-fuzzer 162 110886 47233 0 3 0x4000082 wait syz-fuzzer 162 55886 47233 0 3 0x4000082 thrsleep syz-fuzzer 162 399497 47233 0 3 0x4000082 wait syz-fuzzer 162 110018 47233 0 3 0x4000082 wait syz-fuzzer 162 424586 47233 0 3 0x4000082 thrsleep syz-fuzzer 162 441070 47233 0 3 0x4000082 kqread syz-fuzzer 162 256555 47233 0 3 0x4000082 thrsleep syz-fuzzer 162 464810 47233 0 3 0x4000082 wait syz-fuzzer 162 46208 47233 0 3 0x4000082 wait syz-fuzzer 47233 81660 29050 0 3 0x10008a sigsusp ksh 29050 275867 63114 0 3 0x9a kqread sshd 97048 448502 1 0 3 0x100083 ttyin getty 63114 241125 1 0 3 0x88 kqread sshd 84864 131456 54057 73 3 0x1100090 kqread syslogd 54057 514665 1 0 3 0x100082 netio syslogd 74816 152722 1 0 3 0x100080 kqread resolvd 49785 172041 20093 77 3 0x100092 kqread dhcpleased 87407 521347 20093 77 3 0x100092 kqread dhcpleased 20093 257530 1 0 3 0x80 kqread dhcpleased 21650 426282 0 0 3 0x14200 bored smr 41319 233259 0 0 3 0x14200 pgzero zerothread 37978 320649 0 0 3 0x14200 aiodoned aiodoned 53198 208740 0 0 3 0x14200 syncer update 60011 422299 0 0 3 0x14200 cleaner cleaner 75146 482331 0 0 3 0x14200 reaper reaper 69283 270377 0 0 3 0x14200 pgdaemon pagedaemon 31139 449483 0 0 3 0x14200 bored viomb 89361 198104 0 0 3 0x40014200 acpi0 acpi0 21839 353918 0 0 3 0x40014200 idle1 42689 185466 0 0 3 0x14200 bored softnet 57004 342944 0 0 3 0x14200 bored softnet 56870 1189 0 0 3 0x14200 bored softnet 95338 400010 0 0 3 0x14200 bored softnet 16345 253477 0 0 3 0x14200 bored systqmp 7390 423276 0 0 3 0x14200 bored systq *51390 57393 0 0 7 0x40014200 softclock 10637 183287 0 0 3 0x40014200 idle0 1 87816 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 51390 (softclock) thread 0xffff8000211e9500 (57393) exclusive rwlock netlock r = 0 (0xffffffff8295b4f0) #0 witness_lock+0x44d #1 arptimer+0x22 sys/netinet/if_ether.c:132 #2 timeout_run+0xcc sys/kern/kern_timeout.c:641 #3 softclock_thread+0x134 sys/kern/kern_timeout.c:765 #4 proc_trampoline+0x1c shared rwlock timeout r = 0 (0xffffffff82980500) #0 witness_lock+0x44d #1 timeout_run+0xb7 sys/kern/kern_timeout.c:637 #2 softclock_thread+0x134 sys/kern/kern_timeout.c:765 #3 proc_trampoline+0x1c exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82b00028) #0 witness_lock+0x44d #1 __mp_acquire_count+0x48 sys/kern/kern_lock.c:227 #2 mi_switch+0x3bb sys/kern/sched_bsd.c:415 #3 sleep_finish+0x180 sys/kern/kern_synch.c:417 #4 softclock_thread+0xd9 sys/kern/kern_timeout.c:760 #5 proc_trampoline+0x1c ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10223 6413K 6420K 78643K 11348 0 pcb 13 12K 14K 78643K 17 0 rtable 254 7K 7K 78643K 1378 0 ifaddr 71 16K 16K 78643K 139 0 sysctl 3 1K 1K 78643K 3 0 counters 60 35K 35K 78643K 82 0 ioctlops 0 0K 2K 78643K 232 0 iov 0 0K 32K 78643K 2707 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1285 80K 80K 78643K 4022 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 143 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 5263 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 23 85K 121K 78643K 12643 0 sigio 0 0K 0K 78643K 124 0 proc 56 78K 103K 78643K 1556 0 subproc 117 7K 7K 78643K 247 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 1546 0 in_multi 99 6K 7K 78643K 430 0 ether_multi 1 0K 0K 78643K 78 0 mrt 2 0K 0K 78643K 2 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 247 1102K 1102K 78643K 247 0 exec 0 0K 1K 78643K 2313 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 395 103K 120K 78643K 91710 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 507 0 NDP 11 0K 1K 78643K 58 0 temp 128 4702K 4766K 78643K 33273 0 kqueue 13 20K 28K 78643K 1094 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 1289 0 1285 18 17 1 3 0 8 0 rtentry 112 247 0 127 4 0 4 4 0 8 0 unpcb 144 14703 0 14686 110 109 1 9 0 8 0 syncache 296 142 0 142 29 28 1 1 0 8 1 sackhl 24 1 0 1 1 1 0 1 0 8 0 tcpqe 32 120 0 120 21 20 1 1 0 8 1 tcpcb 776 5965 0 5955 186 178 8 14 0 8 6 arp 120 45 0 25 1 0 1 1 0 8 0 ipq 40 55 0 53 8 7 1 1 0 8 0 ipqe 40 267 0 265 8 7 1 1 0 8 0 inpcb 368 25617 0 25604 249 241 8 16 0 8 5 nd6 48 71 0 39 1 0 1 1 0 8 0 kcovpl 48 19 0 10 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 953 0 462 32 1 31 31 0 8 0 art_table 32 954 0 462 4 0 4 4 0 8 0 art_node 16 246 0 136 1 0 1 1 0 8 0 sysvmsgpl 40 10 0 6 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 5261 0 5251 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 18816 0 17355 92 0 92 92 0 8 0 ffsino 272 18816 0 17355 98 0 98 98 0 8 0 nchpl 144 36464 0 34832 63 0 63 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 124632 0 124632 5 4 1 2 0 8 1 percpumem 16 53 0 11 1 0 1 1 0 8 0 kstatmem 264 44 0 22 2 0 2 2 0 8 0 scxspl 216 111576 0 111576 50 47 3 8 0 8 3 plimitpl 152 2939 0 2913 28 26 2 2 0 8 1 sigapl 424 12912 0 12860 7 0 7 7 0 8 0 futexpl 64 119158 0 119156 8 7 1 1 0 8 0 knotepl 120 833 0 0 11 1 10 10 0 8 0 kqueuepl 216 4280 0 4269 81 80 1 12 0 8 0 pipepl 320 5730 0 5699 128 119 9 13 0 8 6 fdescpl 496 12894 0 12860 7 1 6 6 0 8 0 filepl 152 112451 0 112187 190 174 16 21 0 8 5 lockfpl 104 1969 0 1967 1 0 1 1 0 8 0 lockfspl 48 515 0 513 1 0 1 1 0 8 0 sessionpl 144 34 0 17 1 0 1 1 0 8 0 pgrppl 48 172 0 155 1 0 1 1 0 8 0 ucredpl 104 15579 0 15561 1 0 1 1 0 8 0 zombiepl 144 12861 0 12860 2 1 1 1 0 8 0 processpl 1072 12912 0 12860 5 0 5 5 0 8 0 procpl 672 38409 0 38336 19 11 8 9 0 8 0 sosppl 168 320 0 319 18 17 1 1 0 8 0 sockpl 488 42491 0 42457 736 724 12 33 0 8 7 mcl64k 65536 42 0 0 4 1 3 3 0 8 0 mcl16k 16384 49 0 0 5 2 3 3 0 8 0 mcl12k 12288 41 0 0 2 0 2 2 0 8 0 mcl9k 9216 17 0 0 2 0 2 2 0 8 0 mcl8k 8192 25 0 0 3 0 3 3 0 8 0 mcl4k 4096 58 0 0 6 1 5 5 0 8 3 mcl2k2 2112 6 0 0 1 0 1 1 0 8 0 mcl2k 2048 383 0 0 33 11 22 33 0 8 0 mtagpl 96 5 0 0 1 0 1 1 0 8 0 mbufpl 256 1977 0 0 80 1 79 79 0 8 0 bufpl 288 25229 0 18896 453 0 453 453 0 8 0 anonpl 24 2738731 0 2724880 222 112 110 120 0 186 0 amapchunkpl 152 272055 0 271331 129 94 35 45 0 158 2 amappl16 200 31030 0 30660 190 168 22 37 0 8 1 amappl15 192 6 0 6 2 2 0 1 0 8 0 amappl14 184 168 0 156 1 0 1 1 0 8 0 amappl13 176 36 0 34 1 0 1 1 0 8 0 amappl12 168 543 0 534 1 0 1 1 0 8 0 amappl11 160 50 0 40 1 0 1 1 0 8 0 amappl10 152 44 0 31 1 0 1 1 0 8 0 amappl9 144 1045 0 1045 25 24 1 1 0 8 1 amappl8 136 785 0 620 6 0 6 6 0 8 0 amappl7 128 141 0 124 1 0 1 1 0 8 0 amappl6 120 491 0 465 2 1 1 2 0 8 0 amappl5 112 356 0 348 1 0 1 1 0 8 0 amappl4 104 974 0 939 2 1 1 2 0 8 0 amappl3 96 39897 0 39843 2 0 2 2 0 8 0 amappl2 88 13898 0 13814 4 1 3 3 0 8 1 amappl1 80 298218 0 297468 40 22 18 21 0 8 0 amappl 88 90561 0 90342 7 1 6 6 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 12894 0 12860 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 12894 0 12860 1 0 1 1 0 8 0 vmmpekpl 168 119991 0 119918 4 0 4 4 0 8 0 vmmpepl 168 1196700 0 1193925 305 161 144 154 0 357 1 vmsppl 368 12893 0 12860 4 0 4 4 0 8 0 rwobjpl 56 330851 0 323158 134 22 112 114 0 8 0 pdppl 4096 25795 0 25720 368 281 87 93 0 8 12 pvpl 32 5234418 0 5214236 568 368 200 270 0 265 0 pmappl 248 12893 0 12860 4 1 3 3 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 1439 0 545 26 0 26 26 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff825a8139) at panic+0x177 sys/kern/subr_prf.c:198 __assert(ffffffff82621196,ffffffff8266995b,308,ffffffff825797f0) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd8069d51d38) at arptfree+0x12e sys/netinet/if_ether.c:776 arptimer(ffffffff82b1dbe8) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82b1dbe8) at timeout_run+0xcc sys/kern/kern_timeout.c:641 softclock_thread(ffff8000211e9500) at softclock_thread+0x134 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: -7 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp x86_ipi_db(ffff800020dd8ff0) at x86_ipi_db+0x1a 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+0x23 __mp_lock(ffffffff82affe20) at __mp_lock+0x129 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82affe20) at __mp_lock+0x129 sys/kern/kern_lock.c:147 syscall(ffff80002963e360) at syscall+0x424 mi_syscall sys/sys/syscall_mi.h:101 [inline] syscall(ffff80002963e360) at syscall+0x424 sys/arch/amd64/amd64/trap.c:599 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffffa6c0, count: 9 ddb{1}> trace x86_ipi_db(ffff800020dd8ff0) at x86_ipi_db+0x1a 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+0x23 __mp_lock(ffffffff82affe20) at __mp_lock+0x129 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82affe20) at __mp_lock+0x129 sys/kern/kern_lock.c:147 syscall(ffff80002963e360) at syscall+0x424 mi_syscall sys/sys/syscall_mi.h:101 [inline] syscall(ffff80002963e360) at syscall+0x424 sys/arch/amd64/amd64/trap.c:599 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffffa6c0, count: -6