panic: acquiring blockable sleep lock with spinlock or critical section held (kernel_lock) &kernel_lock Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *459189 89704 0 0 0x4000000 0 syz-executor.1 39835 33241 0 0x14000 0x200 1 reaper db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:207 witness_checkorder(ffffffff8261f770,9,0) at witness_checkorder+0x10cc sys/kern/subr_witness.c:820 __mp_lock(ffffffff8261f568) at __mp_lock+0xa1 pageflttrap() at pageflttrap+0x6f sys/arch/amd64/amd64/trap.c:162 kerntrap(ffff800022d72dd0) at kerntrap+0xec sys/arch/amd64/amd64/trap.c:287 alltraps_kern_meltdown(6,0,600,0,fffffd8007de1054,fffffd807d43cf40) at alltraps_kern_meltdown+0x7b frag6_input(ffff800022d73138,ffff800022d73144,2c,18) at frag6_input+0x7d2 sys/netinet6/frag6.c:321 ip_deliver(ffff800022d73138,ffff800022d73144,2c,18) at ip_deliver+0x353 sys/netinet/ip_input.c:665 ip6_input_if(ffff800022d73138,ffff800022d73144,29,0,ffff80000066d000) at ip6_input_if+0x17d4 ip6_ours sys/netinet6/ip6_input.c:518 [inline] ip6_input_if(ffff800022d73138,ffff800022d73144,29,0,ffff80000066d000) at ip6_input_if+0x17d4 sys/netinet6/ip6_input.c:340 ipv6_input(ffff80000066d000,fffffd8068797200) at ipv6_input+0x48 sys/netinet6/ip6_input.c:171 if_input_local(ffff80000066d000,fffffd8068797200,18) at if_input_local+0x121 sys/net/if.c:783 ip6_output(fffffd806f26a100,ffff800000afd500,fffffd806f6c54d0,0,0,fffffd806f6c5460) at ip6_output+0xd59 rip6_output(fffffd806f26a100,fffffd80657ef618,ffff800022d734a8,0) at rip6_output+0x4c0 sys/netinet6/raw_ip6.c:481 end trace frame: 0xffff800022d73540, count: 0 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 acquiring blockable sleep lock with spinlock or critical section held (kernel_lock) &kernel_lock ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:207 witness_checkorder(ffffffff8261f770,9,0) at witness_checkorder+0x10cc sys/kern/subr_witness.c:820 __mp_lock(ffffffff8261f568) at __mp_lock+0xa1 pageflttrap() at pageflttrap+0x6f sys/arch/amd64/amd64/trap.c:162 kerntrap(ffff800022d72dd0) at kerntrap+0xec sys/arch/amd64/amd64/trap.c:287 alltraps_kern_meltdown(6,0,600,0,fffffd8007de1054,fffffd807d43cf40) at alltraps_kern_meltdown+0x7b frag6_input(ffff800022d73138,ffff800022d73144,2c,18) at frag6_input+0x7d2 sys/netinet6/frag6.c:321 ip_deliver(ffff800022d73138,ffff800022d73144,2c,18) at ip_deliver+0x353 sys/netinet/ip_input.c:665 ip6_input_if(ffff800022d73138,ffff800022d73144,29,0,ffff80000066d000) at ip6_input_if+0x17d4 ip6_ours sys/netinet6/ip6_input.c:518 [inline] ip6_input_if(ffff800022d73138,ffff800022d73144,29,0,ffff80000066d000) at ip6_input_if+0x17d4 sys/netinet6/ip6_input.c:340 ipv6_input(ffff80000066d000,fffffd8068797200) at ipv6_input+0x48 sys/netinet6/ip6_input.c:171 if_input_local(ffff80000066d000,fffffd8068797200,18) at if_input_local+0x121 sys/net/if.c:783 ip6_output(fffffd806f26a100,ffff800000afd500,fffffd806f6c54d0,0,0,fffffd806f6c5460) at ip6_output+0xd59 rip6_output(fffffd806f26a100,fffffd80657ef618,ffff800022d734a8,0) at rip6_output+0x4c0 sys/netinet6/raw_ip6.c:481 rip6_usrreq(fffffd80657ef618,9,fffffd806f26a100,0,0,ffff800020a893d8) at rip6_usrreq+0x5cd sys/netinet6/raw_ip6.c:670 sosend(fffffd80657ef618,0,ffff800022d736d8,0,0,0) at sosend+0x668 sys/kern/uipc_socket.c:524 dofilewritev(ffff800020a893d8,3,ffff800022d736d8,0,ffff800022d737e0) at dofilewritev+0x1ac sys/kern/sys_generic.c:364 sys_write(ffff800020a893d8,ffff800022d73778,ffff800022d737e0) at sys_write+0x83 sys/kern/sys_generic.c:284 syscall(ffff800022d73850) at syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800022d73850) at syscall+0x552 sys/arch/amd64/amd64/trap.c:555 Xsyscall(6,0,c,0,3,78415ea30e0) at Xsyscall+0x128 end of kernel end trace frame: 0x7870c195b10, count: -20 ddb{0}> show registers rdi 0xffffffff819f49b7 db_enter+0x17 rsi 0x392f __ALIGN_SIZE+0x292f rbp 0xffff800022d72b30 rbx 0xffff800022d72be0 rdx 0x3930 __ALIGN_SIZE+0x2930 rcx 0xffff800021950000 rax 0xffff800021950000 r8 0xffffffff81788e23 kprintf+0x173 r9 0x1 r10 0x25 r11 0x7d82392101179cbb r12 0x3000000008 r13 0xffff800022d72b40 r14 0x100 r15 0x1 rip 0xffffffff819f49b8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800022d72b20 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.1) pid=459189 stat=onproc flags process=0 proc=4000000 pri=86, usrpri=86, nice=20 forw=0xffffffffffffffff, list=0xffff800020a88c70,0xffffffff8264e688 process=0xffff800020addc00 user=0xffff800022d6e000, vmspace=0xfffffd807f00ca10 estcpu=36, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 89704 292752 46022 0 2 0 syz-executor.1 89704 405884 46022 0 3 0x4000080 netio syz-executor.1 *89704 459189 46022 0 7 0x4000000 syz-executor.1 62741 271769 41797 0 3 0x82 nanosleep syz-executor.0 46022 132257 41797 0 3 0x82 nanosleep syz-executor.1 14180 462343 0 0 3 0x14200 bored sosplice 41797 176072 36051 0 3 0x82 thrsleep syz-fuzzer 41797 284224 36051 0 3 0x4000082 thrsleep syz-fuzzer 41797 257376 36051 0 3 0x4000082 thrsleep syz-fuzzer 41797 505709 36051 0 3 0x4000082 thrsleep syz-fuzzer 41797 8000 36051 0 3 0x4000082 thrsleep syz-fuzzer 41797 121716 36051 0 3 0x4000082 kqread syz-fuzzer 41797 459816 36051 0 3 0x4000082 thrsleep syz-fuzzer 41797 483888 36051 0 3 0x4000082 thrsleep syz-fuzzer 41797 354656 36051 0 3 0x4000082 thrsleep syz-fuzzer 41797 76277 36051 0 3 0x4000082 thrsleep syz-fuzzer 36051 298941 19071 0 3 0x10008a pause ksh 19071 350020 94383 0 3 0x92 select sshd 84013 83779 1 0 3 0x100083 ttyin getty 94383 328938 1 0 3 0x80 select sshd 79088 196852 22789 74 3 0x100092 bpf pflogd 22789 191816 1 0 3 0x80 netio pflogd 50073 170603 29947 73 3 0x100090 kqread syslogd 29947 156014 1 0 3 0x100082 netio syslogd 37219 259602 1 77 3 0x100090 poll dhclient 36931 81879 1 0 3 0x80 poll dhclient 13443 270559 0 0 2 0x14200 zerothread 87922 424726 0 0 3 0x14200 aiodoned aiodoned 45507 516570 0 0 3 0x14200 syncer update 47600 419717 0 0 3 0x14200 cleaner cleaner 33241 39835 0 0 7 0x14200 reaper 2587 111966 0 0 3 0x14200 pgdaemon pagedaemon 52258 426339 0 0 3 0x14200 bored crynlk 6824 516313 0 0 3 0x14200 bored crypto 41724 327957 0 0 3 0x40014200 acpi0 acpi0 83087 133106 0 0 3 0x40014200 idle1 13696 466000 0 0 3 0x14200 bored softnet 22337 470439 0 0 3 0x14200 bored systqmp 25991 229648 0 0 3 0x14200 bored systq 21280 227251 0 0 3 0x40014200 bored softclock 74093 523149 0 0 3 0x40014200 idle0 67086 436158 0 0 3 0x14200 bored smr 1 33244 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks CPU 0: exclusive mutex /syzkaller/managers/multicore/kernel/sys/netinet6/frag6.c:57 r = 0 (0xffffffff824d5590) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 frag6_input+0x237 sys/netinet6/frag6.c:183 #4 ip_deliver+0x353 sys/netinet/ip_input.c:665 #5 ip6_input_if+0x17d4 ip6_ours sys/netinet6/ip6_input.c:518 [inline] #5 ip6_input_if+0x17d4 sys/netinet6/ip6_input.c:340 #6 ipv6_input+0x48 sys/netinet6/ip6_input.c:171 #7 if_input_local+0x121 sys/net/if.c:783 #8 ip6_output+0xd59 #9 rip6_output+0x4c0 sys/netinet6/raw_ip6.c:481 #10 rip6_usrreq+0x5cd sys/netinet6/raw_ip6.c:670 #11 sosend+0x668 sys/kern/uipc_socket.c:524 #12 dofilewritev+0x1ac sys/kern/sys_generic.c:364 #13 sys_write+0x83 sys/kern/sys_generic.c:284 #14 syscall+0x552 mi_syscall sys/sys/syscall_mi.h:92 [inline] #14 syscall+0x552 sys/arch/amd64/amd64/trap.c:555 #15 Xsyscall+0x128 CPU 1: exclusive kernel: protection fault trap, code=0 Faulted in DDB; continuing... ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9601 6590K 14775K 78643K 17454 0 0 pcb 14 8K 8K 78643K 343 0 0 rtable 108 4K 4K 78643K 1121 0 0 ifaddr 81 17K 18K 78643K 406 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1609 0 0 iov 0 0K 28K 78643K 239 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1202 75K 77K 78643K 3737 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 5K 78643K 39 0 0 VM map 2 1K 1K 78643K 4 0 0 sem 12 0K 1K 78643K 311 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 5 13K 25K 78643K 2697 0 0 sigio 0 0K 0K 78643K 26 0 0 proc 54 51K 83K 78643K 992 0 0 subproc 32 2K 2K 78643K 187 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 ip_moptions 0 0K 0K 78643K 188 0 0 in_multi 33 2K 2K 78643K 184 0 0 ether_multi 1 0K 0K 78643K 13 0 0 mrt 0 0K 0K 78643K 10 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 102 450K 450K 78643K 102 0 0 exec 0 0K 1K 78643K 532 0 0 pagedep 1 8K 8K 78643K 1 0 0 inodedep 1 32K 32K 78643K 1 0 0 newblk 1 0K 0K 78643K 1 0 0 VM swap 7 26K 26K 78643K 7 0 0 UVM amap 98 21K 30K 78643K 9612 0 0 UVM aobj 98 3K 3K 78643K 108 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 2 0K 0K 78643K 290 0 0 NDP 19 0K 0K 78643K 122 0 0 temp 221 3556K 3652K 78643K 33060 0 0 kqueue 0 0K 0K 78643K 17 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 25 0 19 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 145 0 143 1 0 1 1 0 8 0 rtentry 112 153 0 109 2 0 2 2 0 8 0 unpcb 120 855 0 845 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 8965 0 8965 3 3 0 2 0 8 0 tcpcb 544 517 0 513 1 0 1 1 0 8 0 inpcb 280 1537 0 1529 6 5 1 2 0 8 0 rttmr 72 3 0 3 3 3 0 1 0 8 0 ip6q 72 1 0 0 1 0 1 1 0 8 0 ip6af 48 1 0 0 1 0 1 1 0 8 0 nd6 48 33 0 27 1 0 1 1 0 8 0 pkpcb 40 11 0 11 4 3 1 1 0 8 1 swfcl 56 3 0 0 1 0 1 1 0 8 0 ppxss 1128 57 0 57 6 5 1 1 0 8 1 pffrag 232 5 0 5 2 2 0 1 0 482 0 pffrnode 88 5 0 5 2 2 0 1 0 8 0 pffrent 40 13 0 13 2 2 0 1 0 8 0 pfosfp 40 846 0 423 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 80 0 50 1 0 1 1 0 8 0 pfstkey 112 80 0 50 1 0 1 1 0 8 0 pfstate 328 80 0 50 3 0 3 3 0 8 0 pfrule 1360 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 256 600 0 409 13 1 12 13 0 8 0 art_table 32 601 0 409 2 0 2 2 0 8 0 art_node 16 147 0 107 1 0 1 1 0 8 0 sysvmsgpl 40 8 0 0 1 0 1 1 0 8 0 semapl 112 309 0 299 1 0 1 1 0 8 0 shmpl 112 106 0 10 3 0 3 3 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 5579 0 4162 47 0 47 47 0 8 0 ffsino 272 5579 0 4162 96 0 96 96 0 8 0 nchpl 144 9494 0 7860 62 0 62 62 0 8 0 uvmvnodes 72 5926 0 0 108 0 108 108 0 8 0 vnodes 200 5926 0 0 312 0 312 312 0 8 0 namei 1024 30579 0 30579 2 1 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vmpool 552 2 0 2 1 1 0 1 0 8 0 scsiplug 64 7 0 7 5 5 0 1 0 8 0 scxspl 192 26633 0 26633 18 17 1 7 0 8 1 plimitpl 152 247 0 239 1 0 1 1 0 8 0 sigapl 432 2870 0 2855 3 1 2 3 0 8 0 futexpl 56 34095 0 34095 1 0 1 1 0 8 1 knotepl 112 656 0 637 1 0 1 1 0 8 0 kqueuepl 104 574 0 572 1 0 1 1 0 8 0 pipepl 112 1710 0 1691 3 2 1 2 0 8 0 fdescpl 488 2871 0 2855 3 0 3 3 0 8 0 filepl 152 17221 0 17121 8 3 5 6 0 8 1 lockfpl 104 875 0 875 2 1 1 1 0 8 1 lockfspl 48 301 0 301 2 1 1 1 0 8 1 sessionpl 112 27 0 16 1 0 1 1 0 8 0 pgrppl 48 53 0 42 1 0 1 1 0 8 0 ucredpl 96 3201 0 3192 1 0 1 1 0 8 0 zombiepl 144 2855 0 2854 2 1 1 1 0 8 0 processpl 896 2887 0 2854 4 0 4 4 0 8 0 procpl 632 8399 0 8355 8 3 5 5 0 8 1 srpgc 64 21 0 21 5 5 0 1 0 8 0 sosppl 128 37 0 37 7 6 1 1 0 8 1 sockpl 384 2577 0 2557 5 2 3 4 0 8 0 mcl64k 65536 11 0 0 2 0 2 2 0 8 0 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl12k 12288 14 0 0 2 0 2 2 0 8 0 mcl9k 9216 14 0 0 1 0 1 1 0 8 0 mcl8k 8192 13 0 0 2 0 2 2 0 8 0 mcl4k 4096 15 0 0 2 0 2 2 0 8 0 mcl2k2 2112 6 0 0 1 0 1 1 0 8 0 mcl2k 2048 227 0 0 27 2 25 27 0 8 0 mtagpl 80 41 0 0 1 0 1 1 0 8 0 mbufpl 256 303 0 0 16 0 16 16 0 8 0 bufpl 256 11093 0 4074 439 0 439 439 0 8 0 anonpl 16 252956 0 240425 96 30 66 66 0 124 9 amapchunkpl 152 17415 0 17303 31 25 6 19 0 158 0 amappl16 192 12912 0 12213 79 35 44 48 0 8 8 amappl15 184 151 0 150 4 3 1 1 0 8 0 amappl14 176 312 0 306 1 0 1 1 0 8 0 amappl13 168 411 0 409 3 2 1 1 0 8 0 amappl12 160 922 0 922 2 2 0 1 0 8 0 amappl11 152 790 0 774 1 0 1 1 0 8 0 amappl10 144 294 0 290 1 0 1 1 0 8 0 amappl9 136 726 0 722 1 0 1 1 0 8 0 amappl8 128 257 0 234 1 0 1 1 0 8 0 amappl7 120 268 0 258 1 0 1 1 0 8 0 amappl6 112 747 0 739 1 0 1 1 0 8 0 amappl5 104 1121 0 1106 1 0 1 1 0 8 0 amappl4 96 3340 0 3310 1 0 1 1 0 8 0 amappl3 88 475 0 465 1 0 1 1 0 8 0 amappl2 80 21778 0 21705 3 0 3 3 0 8 0 amappl1 72 71122 0 70678 26 16 10 20 0 8 0 amappl 80 8809 0 8769 2 0 2 2 0 84 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma64 64 259 0 259 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 17 0 17 1 1 0 1 0 8 0 aobjpl 64 107 0 10 2 0 2 2 0 8 0 uaddrrnd 24 2873 0 2855 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 2873 0 2855 1 0 1 1 0 8 0 vmmpekpl 168 26185 0 26153 2 0 2 2 0 8 0 vmmpepl 168 354547 0 352714 213 115 98 105 0 357 13 vmsppl 368 2870 0 2855 2 0 2 2 0 8 0 pdppl 4096 5753 0 5714 7 1 6 6 0 8 0 pvpl 32 722391 0 706669 253 90 163 163 0 265 28 pmappl 232 2872 0 2857 3 2 1 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 618 0 8 18 0 18 18 0 8 0