panicW: ARpNoIoNlG_:c aScPhLe _NiOteT mL_OmWaEgRiEc_D cOhNe cSkY: SCmAbLuLf pl2 2c1p4u 23f6r0e46e0 lEisXItT m0o ad i fStopped at savectx+0xb1: movl $0,%gs:0x530 TID PID UID PRFLAGS PFLAGS CPU COMMAND * 63287 72384 0 0x2 0 1 syz-executor.1 339181 54047 0 0x12 0 0 sshd savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffe3eb0, count: 14 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{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd8068e3d900+16 0x0!=0x294b71bdefa9d10b ddb{1}> trace savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffe3eb0, count: -1 ddb{1}> show registers rdi 0 rsi 0 rbp 0xffff800021f832a0 rbx 0 rdx 0x8b rcx 0x2 rax 0x3a r8 0xffffffff8210a11f kprintf+0x16f r9 0x1 r10 0x2 r11 0x8e3d8e4369933997 r12 0 r13 0 r14 0xffff800020ecf128 r15 0 rip 0xffffffff8115d3f1 savectx+0xb1 cs 0x8 rflags 0x46 rsp 0xffff800021f83220 ss 0x10 savectx+0xb1: movl $0,%gs:0x530 ddb{1}> show proc PROC (syz-executor.1) pid=63287 stat=onproc flags process=2 proc=0 pri=16, usrpri=54, nice=20 forw=0xffffffffffffffff, list=0xffff800020ece4f8,0xffff800020ece028 process=0xffff800020ed8bb0 user=0xffff800021f7e000, vmspace=0xfffffd807efff5c0 estcpu=4, cpticks=1, pctcpu=0.3 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 64891 461231 72384 0 2 0 syz-executor.1 *72384 63287 18635 0 7 0x2 syz-executor.1 43727 94719 0 0 3 0x14200 acct acct 56888 434341 0 0 3 0x14200 bored sosplice 16727 100802 18635 0 3 0x82 piperd syz-executor.0 18635 24963 18502 0 3 0x82 thrsleep syz-fuzzer 18635 21350 18502 0 2 0x4000482 syz-fuzzer 18635 399744 18502 0 3 0x4000082 thrsleep syz-fuzzer 18635 427369 18502 0 3 0x4000082 thrsleep syz-fuzzer 18635 229518 18502 0 3 0x4000082 thrsleep syz-fuzzer 18635 380333 18502 0 3 0x4000082 thrsleep syz-fuzzer 18635 150102 18502 0 3 0x4000082 thrsleep syz-fuzzer 18635 399139 18502 0 2 0x4000002 syz-fuzzer 18635 5757 18502 0 2 0x4000002 syz-fuzzer 18635 307095 18502 0 3 0x4000082 thrsleep syz-fuzzer 18502 145376 54047 0 3 0x10008a pause ksh 54047 339181 35917 0 7 0x12 sshd 95172 284131 1 0 3 0x100083 ttyin getty 35917 494958 1 0 3 0x80 select sshd 96642 482120 53704 74 3 0x100092 bpf pflogd 53704 291621 1 0 3 0x80 netio pflogd 33663 426200 57260 73 3 0x100090 kqread syslogd 57260 7559 1 0 3 0x100082 netio syslogd 28511 519518 1 77 3 0x100090 poll dhclient 65936 516021 1 0 3 0x80 poll dhclient 11676 332729 0 0 3 0x14200 bored smr 93434 426086 0 0 2 0x14200 zerothread 99432 289126 0 0 3 0x14200 aiodoned aiodoned 36422 300508 0 0 3 0x14200 syncer update 53506 113263 0 0 3 0x14200 cleaner cleaner 95510 488207 0 0 3 0x14200 reaper reaper 11337 103437 0 0 3 0x14200 pgdaemon pagedaemon 61506 431770 0 0 3 0x14200 bored crynlk 79062 285566 0 0 3 0x14200 bored crypto 84696 117005 0 0 3 0x40014200 acpi0 acpi0 85980 18767 0 0 3 0x40014200 idle1 82492 30185 0 0 3 0x14200 bored softnet 84475 175683 0 0 3 0x14200 bored systqmp 61305 412363 0 0 3 0x14200 bored systq 1718 396561 0 0 3 0x40014200 bored softclock 4793 476608 0 0 3 0x40014200 idle0 1 465712 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks CPU 1: exclusive mutex vmmpekpl r = 0 (0xffffffff8264f970) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 pool_put+0x64 sys/kern/subr_pool.c:792 #4 uvm_unmap_detach+0x231 sys/uvm/uvm_map.c:1581 #5 uvm_map+0xe0c sys/uvm/uvm_map.c:1420 #6 uvm_km_kmemalloc_pla+0x11d sys/uvm/uvm_km.c:335 #7 uvm_uarea_alloc+0x51 sys/uvm/uvm_glue.c:274 #8 fork1+0x271 sys/kern/kern_fork.c:365 #9 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #9 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #10 Xsyscall+0x128 Process 72384 (syz-executor.1) thread 0xffff800020ecf128 (63287) exclusive kernel_lock &kernel_lock r = 1 (0xffffffff8268a470) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 syscall+0x400 mi_syscall sys/sys/syscall_mi.h:93 [inline] #1 syscall+0x400 sys/arch/amd64/amd64/trap.c:570 #2 Xsyscall+0x128 exclusive mutex vmmpekpl r = 0 (0xffffffff8264f970) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 pool_put+0x64 sys/kern/subr_pool.c:792 #4 uvm_unmap_detach+0x231 sys/uvm/uvm_map.c:1581 #5 uvm_map+0xe0c sys/uvm/uvm_map.c:1420 #6 uvm_km_kmemalloc_pla+0x11d sys/uvm/uvm_km.c:335 #7 uvm_uarea_alloc+0x51 sys/uvm/uvm_glue.c:274 #8 fork1+0x271 sys/kern/kern_fork.c:365 #9 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #9 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #10 Xsyscall+0x128 Process 54047 (sshd) thread 0xffff800020ed1390 (339181) exclusive rwlock netlock r = 0 (0xffffffff824b44a8) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 solock+0x5a sys/kern/uipc_socket2.c:282 #2 sosend+0x559 sys/kern/uipc_socket.c:537 #3 dofilewritev+0x1b6 sys/kern/sys_generic.c:365 #4 sys_write+0x83 sys/kern/sys_generic.c:285 #5 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #5 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #6 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9507 6426K 6932K 78643K 10866 0 pcb 13 8K 8K 78643K 57 0 rtable 105 3K 3K 78643K 302 0 ifaddr 63 13K 13K 78643K 85 0 counters 43 33K 34K 78643K 47 0 ioctlops 0 0K 4K 78643K 1472 0 iov 0 0K 12K 78643K 10 0 mount 1 1K 1K 78643K 1 0 vnodes 1219 77K 77K 78643K 1320 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 1K 78643K 2 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 24 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1824 197K 290K 78643K 13058 0 file desc 5 13K 25K 78643K 197 0 sigio 0 0K 0K 78643K 2 0 proc 61 63K 95K 78643K 483 0 subproc 32 2K 2K 78643K 51 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 14 0 in_multi 40 2K 2K 78643K 98 0 ether_multi 1 0K 0K 78643K 10 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 43 201K 201K 78643K 43 0 exec 0 0K 1K 78643K 238 0 pfkey data 0 0K 0K 78643K 2 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 7 26K 26K 78643K 7 0 UVM amap 120 38K 39K 78643K 1569 0 UVM aobj 6 2K 2K 78643K 6 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 40 0 NDP 10 0K 0K 78643K 22 0 temp 88 3033K 3101K 78643K 4351 0 kqueue 3 4K 12K 78643K 20 0 SYN cache 2 16K 16K 78643K 2 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 8 0 2 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 25 0 23 1 0 1 1 0 8 0 rtentry 112 72 0 28 2 0 2 2 0 8 0 unpcb 120 165 0 155 1 0 1 1 0 8 0 syncache 264 5 0 5 2 2 0 1 0 8 0 tcpqe 32 769 0 769 1 1 0 1 0 8 0 tcpcb 544 75 0 71 1 0 1 1 0 8 0 inpcb 280 268 0 261 2 1 1 2 0 8 0 nd6 48 13 0 7 1 0 1 1 0 8 0 pkpcb 40 2 0 2 1 1 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 25 0 4 1 0 1 1 0 8 0 pfstkey 112 25 0 4 1 0 1 1 0 8 0 pfstate 328 25 0 4 2 0 2 2 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 256 328 0 140 14 2 12 13 0 8 0 art_table 32 329 0 140 2 0 2 2 0 8 0 art_node 16 71 0 31 1 0 1 1 0 8 0 sysvmsgpl 40 5 0 4 1 0 1 1 0 8 0 semapl 112 22 0 12 1 0 1 1 0 8 0 shmpl 112 4 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1642 0 236 89 0 89 89 0 8 0 ffsino 272 1642 0 236 96 1 95 95 0 8 0 nchpl 144 2115 0 521 60 0 60 60 0 8 0 uvmvnodes 72 1761 0 0 33 0 33 33 0 8 0 vnodes 208 1761 0 0 93 0 93 93 0 8 0 namei 1024 5744 0 5744 2 1 1 1 0 8 1 percpumem 16 34 0 2 1 0 1 1 0 8 0 vcpupl 1984 1 0 0 1 0 1 1 0 8 0 vmpool 560 1 0 0 1 0 1 1 0 8 0 scsiplug 64 2 0 2 1 0 1 1 0 8 1 scxspl 192 6942 0 6942 8 7 1 7 0 8 1 plimitpl 152 28 0 20 1 0 1 1 0 8 0 sigapl 424 411 0 378 4 0 4 4 0 8 0 futexpl 56 2308 0 2308 1 0 1 1 0 8 1 knotepl 112 92 0 73 1 0 1 1 0 8 0 kqueuepl 144 38 0 36 1 0 1 1 0 8 0 pipelkpl 48 120 0 110 1 0 1 1 0 8 0 pipepl 120 240 0 221 1 0 1 1 0 8 0 fdescpl 496 394 0 378 3 0 3 3 0 8 0 filepl 152 2309 0 2209 6 1 5 5 0 8 1 lockfpl 104 38 0 37 1 0 1 1 0 8 0 lockfspl 48 17 0 16 1 0 1 1 0 8 0 sessionpl 112 19 0 8 1 0 1 1 0 8 0 pgrppl 48 21 0 10 1 0 1 1 0 8 0 ucredpl 96 154 0 144 1 0 1 1 0 8 0 zombiepl 144 378 0 378 2 1 1 1 0 8 1 processpl 984 411 0 378 6 1 5 5 0 8 0 procpl 624 757 0 715 4 0 4 4 0 8 0 sosppl 128 5 0 5 2 1 1 1 0 8 1 sockpl 400 460 0 441 5 2 3 4 0 8 1 mcl64k 65536 4 0 0 1 0 1 1 0 8 0 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl4k 4096 5 0 0 1 0 1 1 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 176 0 0 21 0 21 21 0 8 0 mtagpl 80 24 0 0 1 0 1 1 0 8 0 mbufpl 256 503 0 0 31 0 31 31 0 8 0 bufpl 280 4992 0 135 347 0 347 347 0 8 0 anonpl 16 55042 0 43598 75 1 74 74 0 124 16 amapchunkpl 152 2156 0 2016 9 2 7 8 0 158 0 amappl16 192 1848 0 1094 50 4 46 50 0 8 7 amappl15 184 9 0 7 1 0 1 1 0 8 0 amappl14 176 97 0 89 1 0 1 1 0 8 0 amappl13 168 47 0 42 1 0 1 1 0 8 0 amappl12 160 78 0 73 2 1 1 1 0 8 0 amappl11 152 55 0 40 1 0 1 1 0 8 0 amappl10 144 18 0 11 1 0 1 1 0 8 0 amappl9 136 357 0 355 1 0 1 1 0 8 0 amappl8 128 443 0 411 2 0 2 2 0 8 0 amappl7 120 127 0 114 1 0 1 1 0 8 0 amappl6 112 28 0 23 1 0 1 1 0 8 0 amappl5 104 487 0 471 1 0 1 1 0 8 0 amappl4 96 507 0 476 1 0 1 1 0 8 0 amappl3 88 115 0 108 1 0 1 1 0 8 0 amappl2 80 2187 0 2126 2 0 2 2 0 8 0 amappl1 72 18785 0 18358 23 13 10 18 0 8 0 amappl 80 1028 0 982 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 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 64 5 0 0 1 0 1 1 0 8 0 uaddrrnd 24 395 0 378 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 395 0 378 1 0 1 1 0 8 0 vmmpekpl 168 7070 0 7039 2 0 2 2 0 8 0 vmmpepl 168 55626 0 53746 126 13 113 113 0 357 28 vmsppl 368 394 0 378 2 0 2 2 0 8 0 pdppl 4096 798 0 757 6 0 6 6 0 8 0 pvpl 32 178238 0 163703 181 4 177 177 0 265 34 pmappl 232 394 0 378 3 1 2 2 0 8 1 extentpl 40 53 0 36 1 0 1 1 0 8 0 phpool 112 281 0 9 8 0 8 8 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp x86_ipi_db(ffffffff824b2ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:352 x86_ipi_handler() at x86_ipi_handler+0xc6 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23 x86_bus_space_io_read_1(3f8,5) at x86_bus_space_io_read_1+0x3c sys/arch/amd64/amd64/bus_space.c:639 comcnputc(800,69) at comcnputc+0xb8 sys/dev/ic/com.c:1250 cnputc(69) at cnputc+0x4c sys/dev/cons.c:239 kputchar(69,5,0) at kputchar+0x219 sys/kern/subr_prf.c:343 kprintf() at kprintf+0x15c sys/kern/subr_prf.c:700 panic(ffffffff821fb214) at panic+0xf3 vprintf sys/kern/subr_prf.c:528 [inline] panic(ffffffff821fb214) at panic+0xf3 sys/kern/subr_prf.c:197 pool_cache_get(ffffffff82667020) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82667020) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82667020,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_copym(fffffd8068e3c600,0,580,2) at m_copym+0x174 m_get sys/kern/uipc_mbuf.c:250 [inline] m_copym(fffffd8068e3c600,0,580,2) at m_copym+0x174 sys/kern/uipc_mbuf.c:667 tcp_output(ffff800000a0b100) at tcp_output+0x15ba sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd806eb407d8,9,fffffd8068e3c600,0,0,ffff800020ed1390) at tcp_usrreq+0xa55 end trace frame: 0xffff800020ed7480, count: 0 ddb{0}> trace x86_ipi_db(ffffffff824b2ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:352 x86_ipi_handler() at x86_ipi_handler+0xc6 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23 x86_bus_space_io_read_1(3f8,5) at x86_bus_space_io_read_1+0x3c sys/arch/amd64/amd64/bus_space.c:639 comcnputc(800,69) at comcnputc+0xb8 sys/dev/ic/com.c:1250 cnputc(69) at cnputc+0x4c sys/dev/cons.c:239 kputchar(69,5,0) at kputchar+0x219 sys/kern/subr_prf.c:343 kprintf() at kprintf+0x15c sys/kern/subr_prf.c:700 panic(ffffffff821fb214) at panic+0xf3 vprintf sys/kern/subr_prf.c:528 [inline] panic(ffffffff821fb214) at panic+0xf3 sys/kern/subr_prf.c:197 pool_cache_get(ffffffff82667020) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82667020) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82667020,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_copym(fffffd8068e3c600,0,580,2) at m_copym+0x174 m_get sys/kern/uipc_mbuf.c:250 [inline] m_copym(fffffd8068e3c600,0,580,2) at m_copym+0x174 sys/kern/uipc_mbuf.c:667 tcp_output(ffff800000a0b100) at tcp_output+0x15ba sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd806eb407d8,9,fffffd8068e3c600,0,0,ffff800020ed1390) at tcp_usrreq+0xa55 sosend(fffffd806eb407d8,0,ffff800020ed7548,0,0,80) at sosend+0x671 sys/kern/uipc_socket.c:549 dofilewritev(ffff800020ed1390,4,ffff800020ed7548,0,ffff800020ed7630) at dofilewritev+0x1b6 sys/kern/sys_generic.c:365 sys_write(ffff800020ed1390,ffff800020ed75e0,ffff800020ed7630) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff800020ed76b0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020ed76b0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd9330, count: -19 ddb{0}> machine ddbcpu 1 Stopped at savectx+0xb1: movl $0,%gs:0x530 savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffe3eb0, count: 14 ddb{1}> trace savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffe3eb0, count: -1