panic: WApRoNoIl_NcGa: cShPeL_i NtOeTm _LmOaWgiERcE_Dc hOeNc kS:Y SmCbAuLfLp l 2 cp19u 1f3r8e8e0 380l iEXsIt T m0od ai f ieStopped at savectx+0xb1: movl $0,%gs:0x530 TID PID UID PRFLAGS PFLAGS CPU COMMAND *251602 76677 0 0x2 0 0 syz-executor.1 304536 15018 0 0x12 0 1 sshd savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffc3e00, 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{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd807924f600+16 0x0!=0x2cf2db66438af5ad ddb{0}> trace savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffc3e00, count: -1 ddb{0}> show registers rdi 0 rsi 0 rbp 0xffff800021f911a0 rbx 0 rdx 0xffff800020ec6288 rcx 0 rax 0x3a r8 0xffffffff81276dcf kprintf+0x16f r9 0x1 r10 0x25 r11 0xa32ecc101584873a r12 0 r13 0 r14 0xffff800020ec6288 r15 0 rip 0xffffffff81a323f1 savectx+0xb1 cs 0x8 rflags 0x46 rsp 0xffff800021f91120 ss 0x10 savectx+0xb1: movl $0,%gs:0x530 ddb{0}> show proc PROC (syz-executor.1) pid=251602 stat=onproc flags process=2 proc=0 pri=16, usrpri=54, nice=20 forw=0xffffffffffffffff, list=0xffff800020ec6018,0xffff800020ec7618 process=0xffff800020e93730 user=0xffff800021f8c000, vmspace=0xfffffd806e954178 estcpu=4, cpticks=1, pctcpu=0.1 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 15739 474924 76677 0 2 0 syz-executor.1 78737 524239 84441 0 3 0x80 nanosleep syz-executor.0 78737 210021 84441 0 3 0x4000080 kqread syz-executor.0 78737 8135 84441 0 3 0x4000080 fsleep syz-executor.0 *76677 251602 3169 0 7 0x2 syz-executor.1 51277 224828 0 0 3 0x14200 bored sosplice 84441 485831 3169 0 3 0x82 nanosleep syz-executor.0 3169 222194 81280 0 3 0x82 thrsleep syz-fuzzer 3169 4011 81280 0 3 0x4000082 nanosleep syz-fuzzer 3169 166601 81280 0 3 0x4000082 thrsleep syz-fuzzer 3169 371861 81280 0 2 0x4000002 syz-fuzzer 3169 232269 81280 0 3 0x4000082 thrsleep syz-fuzzer 3169 253859 81280 0 3 0x4000082 thrsleep syz-fuzzer 3169 377772 81280 0 3 0x4000082 thrsleep syz-fuzzer 3169 13526 81280 0 3 0x4000082 thrsleep syz-fuzzer 3169 376428 81280 0 2 0x4000002 syz-fuzzer 3169 143812 81280 0 3 0x4000082 thrsleep syz-fuzzer 81280 144160 15018 0 3 0x10008a pause ksh 15018 304536 64412 0 7 0x12 sshd 45380 275689 1 0 3 0x100083 ttyin getty 64412 57130 1 0 3 0x80 select sshd 6698 429670 85999 74 3 0x100092 bpf pflogd 85999 439587 1 0 3 0x80 netio pflogd 65761 113064 23261 73 3 0x100090 kqread syslogd 23261 387370 1 0 3 0x100082 netio syslogd 9676 298564 1 77 3 0x100090 poll dhclient 24961 355424 1 0 3 0x80 poll dhclient 62803 304467 0 0 3 0x14200 bored smr 99623 62570 0 0 3 0x14200 pgzero zerothread 46809 148793 0 0 3 0x14200 aiodoned aiodoned 20414 321504 0 0 3 0x14200 syncer update 45258 433071 0 0 3 0x14200 cleaner cleaner 24062 254603 0 0 3 0x14200 reaper reaper 87274 388986 0 0 3 0x14200 pgdaemon pagedaemon 69116 215175 0 0 3 0x14200 bored crynlk 23226 287443 0 0 3 0x14200 bored crypto 15495 479087 0 0 3 0x40014200 acpi0 acpi0 21870 249276 0 0 3 0x40014200 idle1 62770 418575 0 0 2 0x14200 softnet 12757 200048 0 0 3 0x14200 bored systqmp 54989 187234 0 0 3 0x14200 bored systq 81536 415508 0 0 3 0x40014200 bored softclock 18291 64066 0 0 3 0x40014200 idle0 1 325558 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks CPU 0: exclusive mutex vmmpekpl r = 0 (0xffffffff82673590) #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 76677 (syz-executor.1) thread 0xffff800020ec6288 (251602) exclusive kernel_lock &kernel_lock r = 1 (0xffffffff8268a7c8) #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 (0xffffffff82673590) #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 15018 (sshd) thread 0xffff800020ede4f0 (304536) exclusive rwlock netlock r = 0 (0xffffffff824ddc08) #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{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9527 6427K 7069K 78643K 11364 0 pcb 13 8K 8K 78643K 110 0 rtable 75 2K 3K 78643K 336 0 ifaddr 79 15K 16K 78643K 149 0 counters 43 33K 34K 78643K 63 0 ioctlops 0 0K 4K 78643K 1495 0 iov 0 0K 32K 78643K 77 0 mount 1 1K 1K 78643K 1 0 vnodes 1223 77K 77K 78643K 1611 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 10 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 1K 78643K 89 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1823 197K 290K 78643K 12980 0 file desc 6 17K 25K 78643K 471 0 sigio 0 0K 0K 78643K 5 0 proc 61 63K 95K 78643K 528 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 51 0 in_multi 60 3K 3K 78643K 135 0 ether_multi 1 0K 0K 78643K 23 0 mrt 0 0K 0K 78643K 6 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 49 228K 228K 78643K 49 0 exec 0 0K 1K 78643K 258 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 131 72K 72K 78643K 2657 0 UVM aobj 19 2K 2K 78643K 28 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 89 0 NDP 13 0K 0K 78643K 29 0 temp 113 3040K 3113K 78643K 13201 0 kqueue 4 6K 16K 78643K 62 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 arp 64 8 0 4 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 41 0 39 1 0 1 1 0 8 0 rtentry 112 62 0 33 2 0 2 2 0 8 0 unpcb 120 261 0 251 1 0 1 1 0 8 0 syncache 264 5 0 5 2 2 0 1 0 8 0 tcpqe 32 1 0 1 1 1 0 1 0 8 0 tcpcb 544 229 0 224 1 0 1 1 0 8 0 inpcb 280 772 0 764 4 2 2 2 0 8 1 rttmr 72 1 0 1 1 1 0 1 0 8 0 nd6 48 10 0 6 1 0 1 1 0 8 0 pffrag 232 4 0 3 2 1 1 1 0 482 0 pffrnode 88 4 0 3 2 1 1 1 0 8 0 pffrent 40 10 0 9 2 1 1 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 56 0 34 1 0 1 1 0 8 0 pfstkey 112 56 0 34 1 0 1 1 0 8 0 pfstate 328 56 0 34 3 0 3 3 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 274 0 138 12 3 9 12 0 8 0 art_table 32 276 0 138 2 0 2 2 0 8 0 art_node 16 61 0 37 1 0 1 1 0 8 0 sysvmsgpl 40 22 0 17 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 83 0 73 1 0 1 1 0 8 0 shmpl 112 26 0 9 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 2260 0 855 89 0 89 89 0 8 0 ffsino 272 2260 0 855 95 0 95 95 0 8 0 nchpl 144 3083 0 1490 60 0 60 60 0 8 0 uvmvnodes 72 2508 0 0 46 0 46 46 0 8 0 vnodes 208 2508 0 0 132 0 132 132 0 8 0 namei 1024 9294 0 9294 3 2 1 1 0 8 1 percpumem 16 42 0 10 1 0 1 1 0 8 0 vcpupl 1984 6 0 0 1 0 1 1 0 8 0 vmpool 560 8 0 2 1 0 1 1 0 8 0 scxspl 192 8648 0 8648 8 7 1 5 0 8 1 plimitpl 152 50 0 42 1 0 1 1 0 8 0 sigapl 424 684 0 651 4 0 4 4 0 8 0 futexpl 56 7333 0 7332 3 2 1 1 0 8 0 knotepl 112 152 0 133 1 0 1 1 0 8 0 kqueuepl 144 161 0 157 1 0 1 1 0 8 0 pipelkpl 48 183 0 173 1 0 1 1 0 8 0 pipepl 120 366 0 347 2 1 1 2 0 8 0 fdescpl 496 668 0 651 3 0 3 3 0 8 0 filepl 152 4714 0 4608 7 2 5 7 0 8 0 lockfpl 104 251 0 250 1 0 1 1 0 8 0 lockfspl 48 73 0 72 1 0 1 1 0 8 0 sessionpl 112 19 0 8 1 0 1 1 0 8 0 pgrppl 48 19 0 8 1 0 1 1 0 8 0 ucredpl 96 686 0 677 1 0 1 1 0 8 0 zombiepl 144 651 0 651 1 0 1 1 0 8 1 processpl 984 684 0 651 5 0 5 5 0 8 0 procpl 624 1831 0 1787 4 0 4 4 0 8 0 sosppl 128 6 0 6 2 2 0 1 0 8 0 sockpl 400 1077 0 1057 6 3 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 4 0 0 1 0 1 1 0 8 0 mcl9k 9216 4 0 0 1 0 1 1 0 8 0 mcl8k 8192 4 0 0 1 0 1 1 0 8 0 mcl4k 4096 7 0 0 1 0 1 1 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 170 0 0 21 0 21 21 0 8 0 mtagpl 80 30 0 0 1 0 1 1 0 8 0 mbufpl 256 408 0 0 23 0 23 23 0 8 0 bufpl 280 4382 0 136 304 0 304 304 0 8 0 anonpl 16 71444 0 57395 60 1 59 59 0 124 0 amapchunkpl 152 4010 0 3869 15 9 6 13 0 158 0 amappl16 192 2950 0 2159 42 2 40 41 0 8 0 amappl15 184 1 0 0 1 0 1 1 0 8 0 amappl14 176 33 0 26 1 0 1 1 0 8 0 amappl13 168 33 0 31 1 0 1 1 0 8 0 amappl12 160 202 0 196 2 1 1 1 0 8 0 amappl11 152 69 0 53 1 0 1 1 0 8 0 amappl10 144 23 0 17 1 0 1 1 0 8 0 amappl9 136 463 0 461 1 0 1 1 0 8 0 amappl8 128 450 0 415 2 0 2 2 0 8 0 amappl7 120 133 0 121 1 0 1 1 0 8 0 amappl6 112 24 0 19 1 0 1 1 0 8 0 amappl5 104 753 0 736 1 0 1 1 0 8 0 amappl4 96 508 0 479 1 0 1 1 0 8 0 amappl3 88 137 0 131 1 0 1 1 0 8 0 amappl2 80 4335 0 4261 2 0 2 2 0 8 0 amappl1 72 25299 0 24863 24 14 10 18 0 8 0 amappl 80 2092 0 2046 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 27 0 9 1 0 1 1 0 8 0 uaddrrnd 24 676 0 653 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 676 0 653 1 0 1 1 0 8 0 vmmpekpl 168 9715 0 9684 2 0 2 2 0 8 0 vmmpepl 168 88441 0 86404 135 42 93 115 0 357 2 vmsppl 368 675 0 653 2 0 2 2 0 8 0 pdppl 4096 1360 0 1312 7 0 7 7 0 8 1 pvpl 32 252752 0 235773 155 10 145 148 0 265 2 pmappl 232 675 0 653 2 0 2 2 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 277 0 11 8 0 8 8 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffc3e00, count: -1 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp x86_ipi_db(ffff800020e00ff0) 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_write_1(3f8,0,65) at x86_bus_space_io_write_1+0x45 sys/arch/amd64/amd64/bus_space.c:759 comcnputc(800,65) at comcnputc+0x131 bus_space_barrier machine/bus.h:481 [inline] comcnputc(800,65) at comcnputc+0x131 sys/dev/ic/com.c:1254 cnputc(65) at cnputc+0x4c sys/dev/cons.c:239 kputchar(65,5,0) at kputchar+0x219 sys/kern/subr_prf.c:343 kprintf() at kprintf+0x15c sys/kern/subr_prf.c:700 panic(ffffffff821fadd6) at panic+0xf3 vprintf sys/kern/subr_prf.c:528 [inline] panic(ffffffff821fadd6) at panic+0xf3 sys/kern/subr_prf.c:197 pool_cache_get(ffffffff8265c188) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff8265c188) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff8265c188,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_copym(fffffd8068fccb00,580,274,2) at m_copym+0x174 m_get sys/kern/uipc_mbuf.c:250 [inline] m_copym(fffffd8068fccb00,580,274,2) at m_copym+0x174 sys/kern/uipc_mbuf.c:667 tcp_output(ffff800000a0c100) at tcp_output+0x15ba sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd806eb3e4b8,9,fffffd8068fccb00,0,0,ffff800020ede4f0) at tcp_usrreq+0xa55 end trace frame: 0xffff800020ecf790, count: 0 ddb{1}> trace x86_ipi_db(ffff800020e00ff0) 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_write_1(3f8,0,65) at x86_bus_space_io_write_1+0x45 sys/arch/amd64/amd64/bus_space.c:759 comcnputc(800,65) at comcnputc+0x131 bus_space_barrier machine/bus.h:481 [inline] comcnputc(800,65) at comcnputc+0x131 sys/dev/ic/com.c:1254 cnputc(65) at cnputc+0x4c sys/dev/cons.c:239 kputchar(65,5,0) at kputchar+0x219 sys/kern/subr_prf.c:343 kprintf() at kprintf+0x15c sys/kern/subr_prf.c:700 panic(ffffffff821fadd6) at panic+0xf3 vprintf sys/kern/subr_prf.c:528 [inline] panic(ffffffff821fadd6) at panic+0xf3 sys/kern/subr_prf.c:197 pool_cache_get(ffffffff8265c188) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff8265c188) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff8265c188,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_copym(fffffd8068fccb00,580,274,2) at m_copym+0x174 m_get sys/kern/uipc_mbuf.c:250 [inline] m_copym(fffffd8068fccb00,580,274,2) at m_copym+0x174 sys/kern/uipc_mbuf.c:667 tcp_output(ffff800000a0c100) at tcp_output+0x15ba sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd806eb3e4b8,9,fffffd8068fccb00,0,0,ffff800020ede4f0) at tcp_usrreq+0xa55 sosend(fffffd806eb3e4b8,0,ffff800020ecf858,0,0,80) at sosend+0x671 sys/kern/uipc_socket.c:549 dofilewritev(ffff800020ede4f0,4,ffff800020ecf858,0,ffff800020ecf940) at dofilewritev+0x1b6 sys/kern/sys_generic.c:365 sys_write(ffff800020ede4f0,ffff800020ecf8f0,ffff800020ecf940) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff800020ecf9c0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020ecf9c0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc7220, count: -19