panic:W ApoRNoIlN_Gc:ac hSPeL_ iNtOeTm _LmOaWgERiEcD_ cOheNc Sk:YS CmAbLuLfp 2l -c5p0u7 6fr57e3e3 1l iEsXItT m0od ia f ieStopped at savectx+0xb1: movl $0,%gs:0x530 TID PID UID PRFLAGS PFLAGS CPU COMMAND *394738 91951 0 0x2 0 1 syz-executor.0 396219 692 0 0x12 0 0 sshd savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffeaa60, 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 0xfffffd806a618800+24 0x5a53175d924a398!=0x5a531f5b33b0c98 ddb{1}> trace savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffeaa60, count: -1 ddb{1}> show registers rdi 0 rsi 0 rbp 0xffff800020ee9880 rbx 0 rdx 0x8b rcx 0x2 rax 0x3a r8 0xffffffff81e379ff kprintf+0x16f r9 0x1 r10 0x2 r11 0xd706d097c2d4fb4c r12 0 r13 0 r14 0xffff800020dec4e8 r15 0 rip 0xffffffff81a2f3f1 savectx+0xb1 cs 0x8 rflags 0x46 rsp 0xffff800020ee9800 ss 0x10 savectx+0xb1: movl $0,%gs:0x530 ddb{1}> show proc PROC (syz-executor.0) pid=394738 stat=onproc flags process=2 proc=0 pri=17, usrpri=52, nice=20 forw=0xffffffffffffffff, list=0xffff800020dec758,0xffff800020ee3888 process=0xffff800020e003e8 user=0xffff800020ee4000, vmspace=0xfffffd807f000cf0 estcpu=2, cpticks=1, pctcpu=0.5 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 68722 341358 91951 0 2 0 syz-executor.0 15046 517608 1563 0 2 0x2 syz-executor.1 *91951 394738 1563 0 7 0x2 syz-executor.0 1563 109044 13133 0 3 0x82 thrsleep syz-fuzzer 1563 108191 13133 0 3 0x4000082 nanosleep syz-fuzzer 1563 146694 13133 0 3 0x4000082 thrsleep syz-fuzzer 1563 328585 13133 0 2 0x4000002 syz-fuzzer 1563 83246 13133 0 3 0x4000082 thrsleep syz-fuzzer 1563 57125 13133 0 2 0x4000002 syz-fuzzer 1563 233483 13133 0 3 0x4000082 thrsleep syz-fuzzer 1563 1002 13133 0 3 0x4000082 thrsleep syz-fuzzer 1563 305714 13133 0 3 0x4000082 thrsleep syz-fuzzer 1563 236181 13133 0 3 0x4000082 thrsleep syz-fuzzer 13133 347515 692 0 3 0x10008a pause ksh 692 396219 25003 0 7 0x12 sshd 56443 319744 1 0 3 0x100083 ttyin getty 25003 77526 1 0 3 0x80 select sshd 29203 407144 86951 74 3 0x100092 bpf pflogd 86951 30791 1 0 3 0x80 netio pflogd 70536 177695 19017 73 3 0x100090 kqread syslogd 19017 465942 1 0 3 0x100082 netio syslogd 33389 236826 1 77 3 0x100090 poll dhclient 93221 329581 1 0 3 0x80 poll dhclient 44503 120282 0 0 3 0x14200 bored smr 89672 231260 0 0 2 0x14200 zerothread 68760 64560 0 0 3 0x14200 aiodoned aiodoned 13675 473758 0 0 3 0x14200 syncer update 14843 259900 0 0 3 0x14200 cleaner cleaner 6399 353660 0 0 3 0x14200 reaper reaper 59400 90935 0 0 3 0x14200 pgdaemon pagedaemon 11261 485883 0 0 3 0x14200 bored crynlk 38344 508523 0 0 3 0x14200 bored crypto 43355 199549 0 0 3 0x40014200 acpi0 acpi0 65468 522294 0 0 3 0x40014200 idle1 64816 212627 0 0 2 0x14200 softnet 26269 387494 0 0 3 0x14200 bored systqmp 77137 468021 0 0 3 0x14200 bored systq 57814 467965 0 0 3 0x40014200 bored softclock 57529 269536 0 0 3 0x40014200 idle0 1 249775 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks CPU 1: exclusive mutex &uvm.fpageqlock r = 0 (0xffffffff828a3dd0) #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 uvm_pmr_getpages+0x34e sys/uvm/uvm_pmemrange.c:941 #4 uvm_pglistalloc+0x362 sys/uvm/uvm_page.c:790 #5 uvm_km_kmemalloc_pla+0x238 sys/uvm/uvm_km.c:367 #6 uvm_uarea_alloc+0x51 sys/uvm/uvm_glue.c:274 #7 fork1+0x271 sys/kern/kern_fork.c:365 #8 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #8 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #9 Xsyscall+0x128 Process 91951 (syz-executor.0) thread 0xffff800020dec4e8 (394738) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff828b3f90) #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 &uvm.fpageqlock r = 0 (0xffffffff828a3dd0) #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 uvm_pmr_getpages+0x34e sys/uvm/uvm_pmemrange.c:941 #4 uvm_pglistalloc+0x362 sys/uvm/uvm_page.c:790 #5 uvm_km_kmemalloc_pla+0x238 sys/uvm/uvm_km.c:367 #6 uvm_uarea_alloc+0x51 sys/uvm/uvm_glue.c:274 #7 fork1+0x271 sys/kern/kern_fork.c:365 #8 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #8 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #9 Xsyscall+0x128 Process 692 (sshd) thread 0xffff800020e5f600 (396219) exclusive rwlock netlock r = 0 (0xffffffff826eda78) #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 9471 6398K 6786K 78643K 10665 0 pcb 13 8K 8K 78643K 31 0 rtable 97 3K 3K 78643K 201 0 ifaddr 44 10K 11K 78643K 49 0 sysctl 2 0K 0K 78643K 2 0 counters 43 33K 33K 78643K 43 0 ioctlops 0 0K 4K 78643K 1473 0 iov 0 0K 12K 78643K 4 0 mount 1 1K 1K 78643K 1 0 vnodes 1222 77K 77K 78643K 1254 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 8 0K 0K 78643K 14 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1824 197K 290K 78643K 13058 0 file desc 5 13K 25K 78643K 74 0 proc 60 63K 83K 78643K 444 0 subproc 32 2K 2K 78643K 34 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 1 0 in_multi 39 2K 2K 78643K 42 0 ether_multi 1 0K 0K 78643K 2 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 19 95K 95K 78643K 19 0 exec 0 0K 1K 78643K 211 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 115 22K 25K 78643K 1163 0 UVM aobj 2 2K 2K 78643K 2 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 8 0 NDP 6 0K 0K 78643K 10 0 temp 68 3844K 3908K 78643K 2131 0 kqueue 3 4K 6K 78643K 6 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 6 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 45 0 5 2 0 2 2 0 8 0 unpcb 120 33 0 23 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 47 0 47 1 1 0 1 0 8 0 tcpcb 544 16 0 12 1 0 1 1 0 8 0 inpcb 280 70 0 63 2 0 2 2 0 8 1 nd6 48 6 0 0 1 0 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 15 0 0 1 0 1 1 0 8 0 pfstkey 112 15 0 0 1 0 1 1 0 8 0 pfstate 328 15 0 0 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 256 188 0 4 12 0 12 12 0 8 0 art_table 32 189 0 4 2 0 2 2 0 8 0 art_node 16 44 0 8 1 0 1 1 0 8 0 sysvmsgpl 40 6 0 2 1 0 1 1 0 8 0 semupl 112 4 0 4 1 0 1 1 0 8 1 semapl 112 6 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1482 0 75 89 0 89 89 0 8 0 ffsino 272 1482 0 75 95 0 95 95 0 8 0 nchpl 144 1763 0 153 60 0 60 60 0 8 0 uvmvnodes 72 1558 0 0 29 0 29 29 0 8 0 vnodes 208 1558 0 0 82 0 82 82 0 8 0 namei 1024 4620 0 4620 1 0 1 1 0 8 1 percpumem 16 32 0 0 1 0 1 1 0 8 0 scxspl 192 5239 0 5239 8 1 7 7 0 8 7 plimitpl 152 15 0 7 1 0 1 1 0 8 0 sigapl 424 289 0 258 4 0 4 4 0 8 0 futexpl 56 587 0 587 1 0 1 1 0 8 1 knotepl 112 65 0 46 1 0 1 1 0 8 0 kqueuepl 144 14 0 12 1 0 1 1 0 8 0 pipelkpl 48 83 0 73 1 0 1 1 0 8 0 pipepl 120 166 0 147 1 0 1 1 0 8 0 fdescpl 496 274 0 258 3 0 3 3 0 8 0 filepl 152 1377 0 1276 6 0 6 6 0 8 2 lockfpl 104 17 0 16 1 0 1 1 0 8 0 lockfspl 48 7 0 6 1 0 1 1 0 8 0 sessionpl 112 18 0 7 1 0 1 1 0 8 0 pgrppl 48 18 0 7 1 0 1 1 0 8 0 ucredpl 96 58 0 49 1 0 1 1 0 8 0 zombiepl 144 258 0 258 1 0 1 1 0 8 1 processpl 984 289 0 258 5 0 5 5 0 8 1 procpl 624 398 0 358 4 0 4 4 0 8 0 sockpl 400 128 0 109 3 0 3 3 0 8 1 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 1 0 0 1 0 1 1 0 8 0 mcl4k 4096 3 0 0 1 0 1 1 0 8 0 mcl2k 2048 202 0 0 25 0 25 25 0 8 0 mtagpl 80 6 0 0 1 0 1 1 0 8 0 mbufpl 256 232 0 0 14 0 14 14 0 8 0 bufpl 280 3421 0 133 235 0 235 235 0 8 0 anonpl 16 44071 0 29278 77 1 76 76 0 124 15 amapchunkpl 152 1298 0 1164 8 0 8 8 0 158 1 amappl16 192 1280 0 478 52 0 52 52 0 8 11 amappl15 184 1 0 1 1 1 0 1 0 8 0 amappl14 176 45 0 39 1 0 1 1 0 8 0 amappl13 168 72 0 67 1 0 1 1 0 8 0 amappl12 160 29 0 24 1 0 1 1 0 8 0 amappl11 152 53 0 38 1 0 1 1 0 8 0 amappl10 144 18 0 12 1 0 1 1 0 8 0 amappl9 136 383 0 382 1 0 1 1 0 8 0 amappl8 128 342 0 313 2 0 2 2 0 8 0 amappl7 120 120 0 107 1 0 1 1 0 8 0 amappl6 112 23 0 20 1 0 1 1 0 8 0 amappl5 104 157 0 142 1 0 1 1 0 8 0 amappl4 96 509 0 480 1 0 1 1 0 8 0 amappl3 88 131 0 121 1 0 1 1 0 8 0 amappl2 80 1254 0 1191 2 0 2 2 0 8 0 amappl1 72 16007 0 15579 23 6 17 18 0 8 7 amappl 80 648 0 607 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 1 0 0 1 0 1 1 0 8 0 uaddrrnd 24 274 0 258 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 274 0 258 1 0 1 1 0 8 0 vmmpekpl 168 6218 0 6188 2 0 2 2 0 8 0 vmmpepl 168 40404 0 38487 115 2 113 113 0 357 28 vmsppl 368 273 0 258 2 0 2 2 0 8 0 pdppl 4096 555 0 516 6 0 6 6 0 8 0 pvpl 32 145778 0 127936 180 0 180 180 0 265 31 pmappl 232 273 0 258 2 0 2 2 0 8 1 extentpl 40 53 0 36 1 0 1 1 0 8 0 phpool 112 262 0 3 8 0 8 8 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp x86_ipi_db(ffffffff82700ff0) 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(ffffffff823e71fa) at panic+0xf3 vprintf sys/kern/subr_prf.c:528 [inline] panic(ffffffff823e71fa) at panic+0xf3 sys/kern/subr_prf.c:197 pool_cache_get(ffffffff8290ecd8) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff8290ecd8) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff8290ecd8,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_gethdr(2,2) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 tcp_output(ffff800000ad7760) at tcp_output+0x14e6 tcp_usrreq(fffffd806f680640,9,fffffd806a1fdd00,0,0,ffff800020e5f600) at tcp_usrreq+0xa55 end trace frame: 0xffff800020e47270, count: 0 ddb{0}> trace x86_ipi_db(ffffffff82700ff0) 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(ffffffff823e71fa) at panic+0xf3 vprintf sys/kern/subr_prf.c:528 [inline] panic(ffffffff823e71fa) at panic+0xf3 sys/kern/subr_prf.c:197 pool_cache_get(ffffffff8290ecd8) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff8290ecd8) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff8290ecd8,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_gethdr(2,2) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 tcp_output(ffff800000ad7760) at tcp_output+0x14e6 tcp_usrreq(fffffd806f680640,9,fffffd806a1fdd00,0,0,ffff800020e5f600) at tcp_usrreq+0xa55 sosend(fffffd806f680640,0,ffff800020e47338,0,0,80) at sosend+0x671 sys/kern/uipc_socket.c:549 dofilewritev(ffff800020e5f600,4,ffff800020e47338,0,ffff800020e47420) at dofilewritev+0x1b6 sys/kern/sys_generic.c:365 sys_write(ffff800020e5f600,ffff800020e473d0,ffff800020e47420) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff800020e474a0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020e474a0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffe23a0, 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: 0x7f7ffffeaa60, count: 14 ddb{1}> trace savectx() at savectx+0xb1 end of kernel end trace frame: 0x7f7ffffeaa60, count: -1