panic: pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd806a6faf00+16 0x0!=0x9eb9ada25fb28655 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 120595 39926 0 0 0x4000080 1 syz-executor.1 *500917 42680 0 0 0x4000000 0 syz-executor.0 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8240e744) at panic+0x164 sys/kern/subr_prf.c:218 pool_cache_get(ffffffff828d47c8) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff828d47c8) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff828d47c8,1) at pool_get+0x91 sys/kern/subr_pool.c:572 m_get(1,1) at m_get+0x4c sys/kern/uipc_mbuf.c:250 m_getuio(ffff800020ed4bd8,1,2000,ffff800020ed4ca0) at m_getuio+0xbe sys/kern/uipc_socket.c:592 sosend(fffffd8063a47998,0,ffff800020ed4ca0,0,0,80) at sosend+0x54e sys/kern/uipc_socket.c:542 sendit(ffff800020eb2c70,a,ffff800020ed4d80,0,ffff800020ed4e60) at sendit+0x52b sys/kern/uipc_syscalls.c:657 sys_sendto(ffff800020eb2c70,ffff800020ed4e18,ffff800020ed4e60) at sys_sendto+0x80 sys/kern/uipc_syscalls.c:522 syscall(ffff800020ed4ee0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020ed4ee0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x5dbec82e240, count: 4 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 0xfffffd806a6faf00+16 0x0!=0x9eb9ada25fb28655 ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8240e744) at panic+0x164 sys/kern/subr_prf.c:218 pool_cache_get(ffffffff828d47c8) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff828d47c8) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff828d47c8,1) at pool_get+0x91 sys/kern/subr_pool.c:572 m_get(1,1) at m_get+0x4c sys/kern/uipc_mbuf.c:250 m_getuio(ffff800020ed4bd8,1,2000,ffff800020ed4ca0) at m_getuio+0xbe sys/kern/uipc_socket.c:592 sosend(fffffd8063a47998,0,ffff800020ed4ca0,0,0,80) at sosend+0x54e sys/kern/uipc_socket.c:542 sendit(ffff800020eb2c70,a,ffff800020ed4d80,0,ffff800020ed4e60) at sendit+0x52b sys/kern/uipc_syscalls.c:657 sys_sendto(ffff800020eb2c70,ffff800020ed4e18,ffff800020ed4e60) at sys_sendto+0x80 sys/kern/uipc_syscalls.c:522 syscall(ffff800020ed4ee0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020ed4ee0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x5dbec82e240, count: -11 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800020ed4900 rbx 0xffff800020ed49b0 rdx 0x8b rcx 0x2 rax 0x1 r8 0xffff800020ed48c0 r9 0xffffffff8167b47f kprintf+0x16f r10 0x1 r11 0x220bcddf70e71dd7 r12 0x3000000008 r13 0xffff800020ed4910 r14 0x100 r15 0x1 rip 0xffffffff8215e708 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020ed48f0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.0) pid=500917 stat=onproc flags process=0 proc=4000000 pri=32, usrpri=57, nice=20 forw=0xffffffffffffffff, list=0xffff800020eb2780,0xffff800020eb38d8 process=0xffff800020eb4bd0 user=0xffff800020ecf000, vmspace=0xfffffd807effea10 estcpu=36, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 39926 462747 12976 0 2 0 syz-executor.1 39926 120595 12976 0 7 0x4000080 syz-executor.1 42680 86236 8930 0 2 0 syz-executor.0 *42680 500917 8930 0 7 0x4000000 syz-executor.0 42680 231467 8930 0 3 0x4000080 fsleep syz-executor.0 8141 506313 0 0 3 0x14200 bored sosplice 12976 150089 63811 0 3 0x82 nanosleep syz-executor.1 8930 59897 63811 0 3 0x82 nanosleep syz-executor.0 63811 147634 65784 0 3 0x82 thrsleep syz-fuzzer 63811 50586 65784 0 3 0x4000082 thrsleep syz-fuzzer 63811 448780 65784 0 3 0x4000082 thrsleep syz-fuzzer 63811 471837 65784 0 3 0x4000082 thrsleep syz-fuzzer 63811 182868 65784 0 3 0x4000082 kqread syz-fuzzer 63811 238056 65784 0 3 0x4000082 thrsleep syz-fuzzer 63811 32983 65784 0 3 0x4000082 thrsleep syz-fuzzer 63811 306168 65784 0 3 0x4000082 thrsleep syz-fuzzer 65784 389464 58690 0 3 0x10008a pause ksh 58690 67215 49546 0 3 0x92 select sshd 35064 199877 1 0 3 0x100083 ttyin getty 49546 70197 1 0 3 0x80 select sshd 37342 471232 86999 74 3 0x100092 bpf pflogd 86999 79440 1 0 3 0x80 netio pflogd 51188 303446 51001 73 3 0x100090 kqread syslogd 51001 7600 1 0 3 0x100082 netio syslogd 62392 266999 1 77 3 0x100090 poll dhclient 6688 104488 1 0 3 0x80 poll dhclient 94196 167222 0 0 3 0x14200 bored smr 224 6251 0 0 2 0x14200 zerothread 22957 347961 0 0 3 0x14200 aiodoned aiodoned 71185 111336 0 0 3 0x14200 syncer update 64348 209328 0 0 3 0x14200 cleaner cleaner 26257 109709 0 0 3 0x14200 reaper reaper 83021 298867 0 0 3 0x14200 pgdaemon pagedaemon 44308 247837 0 0 3 0x14200 bored crynlk 29546 392115 0 0 3 0x14200 bored crypto 42073 445552 0 0 3 0x40014200 acpi0 acpi0 16687 221588 0 0 3 0x40014200 idle1 82139 190242 0 0 3 0x14200 bored softnet 52643 218764 0 0 3 0x14200 bored systqmp 31259 260581 0 0 3 0x14200 bored systq 86872 55259 0 0 3 0x40014200 bored softclock 54185 413269 0 0 3 0x40014200 idle0 1 503183 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9501 6408K 6923K 78643K 11455 0 pcb 13 8K 8K 78643K 73 0 rtable 133 8K 8K 78643K 661 0 ifaddr 75 16K 16K 78643K 121 0 sysctl 2 0K 0K 78643K 2 0 counters 43 33K 34K 78643K 55 0 ioctlops 0 0K 4K 78643K 1576 0 iov 0 0K 16K 78643K 35 0 mount 1 1K 1K 78643K 1 0 vnodes 1224 77K 77K 78643K 1462 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 13 0 VM map 2 1K 1K 78643K 2 0 sem 12 1K 1K 78643K 148 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1824 197K 290K 78643K 13058 0 file desc 6 17K 25K 78643K 615 0 sigio 0 0K 0K 78643K 3 0 proc 62 63K 95K 78643K 488 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 38 0 in_multi 53 3K 3K 78643K 108 0 ether_multi 1 0K 0K 78643K 9 0 mrt 1 0K 0K 78643K 3 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 224 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 179 75K 91K 78643K 2976 0 UVM aobj 42 4K 4K 78643K 50 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 41 0 NDP 10 0K 0K 78643K 24 0 temp 119 3870K 3938K 78643K 5846 0 kqueue 3 4K 12K 78643K 23 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 7 0 0 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 88 423 0 417 1 0 1 1 0 8 0 rtentry 112 66 0 19 2 0 2 2 0 8 0 unpcb 120 275 0 265 1 0 1 1 0 8 0 syncache 272 5 0 5 2 2 0 1 0 8 0 tcpqe 32 125 0 125 1 1 0 1 0 8 0 tcpcb 592 156 0 148 4 2 2 2 0 8 1 inpcb 296 503 0 494 5 3 2 2 0 8 1 rttmr 72 1 0 1 1 0 1 1 0 8 1 nd6 48 20 0 13 1 0 1 1 0 8 0 pkpcb 40 4 0 4 2 2 0 1 0 8 0 ppxss 1136 1 0 1 1 1 0 1 0 8 0 pfstscr 40 4 0 4 1 1 0 1 0 8 0 pffrag 232 6 0 5 2 1 1 1 0 482 0 pffrnode 88 6 0 5 2 1 1 1 0 8 0 pffrent 40 15 0 14 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 pfrktable 1344 18 0 9 1 0 1 1 0 8 0 pftag 88 1 0 0 1 0 1 1 0 8 0 pfqueue 264 2 0 2 1 1 0 1 0 8 0 pfstitem 24 12 0 10 1 0 1 1 0 8 0 pfstkey 112 16 0 14 1 0 1 1 0 8 0 pfstate 328 14 0 12 2 1 1 2 0 8 0 pfrule 1360 36 0 19 3 1 2 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 288 0 63 18 3 15 17 0 8 0 art_table 32 289 0 63 3 1 2 3 0 8 0 art_node 16 65 0 23 1 0 1 1 0 8 0 sysvmsgpl 40 33 0 24 2 1 1 1 0 8 0 semupl 112 4 0 4 2 2 0 1 0 8 0 semapl 112 139 0 129 1 0 1 1 0 8 0 shmpl 112 47 0 8 2 0 2 2 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 2130 0 726 88 0 88 88 0 8 0 ffsino 272 2130 0 726 94 0 94 94 0 8 0 nchpl 144 3336 0 1740 60 0 60 60 0 8 0 uvmvnodes 72 2365 0 0 43 0 43 43 0 8 0 vnodes 208 2365 0 0 125 0 125 125 0 8 0 namei 1024 9148 0 9148 2 1 1 1 0 8 1 percpumem 16 38 0 6 1 0 1 1 0 8 0 vcpupl 1984 6 0 1 1 0 1 1 0 8 0 vmpool 560 8 0 3 1 0 1 1 0 8 0 pfiaddrpl 120 8 0 2 1 0 1 1 0 8 0 scsiplug 72 1 0 1 1 1 0 1 0 8 0 scxspl 200 9095 0 9095 11 10 1 7 0 8 1 plimitpl 152 61 0 53 1 0 1 1 0 8 0 sigapl 424 831 0 798 4 0 4 4 0 8 0 futexpl 56 7225 0 7224 3 2 1 1 0 8 0 knotepl 112 82 0 62 1 0 1 1 0 8 0 kqueuepl 152 63 0 61 1 0 1 1 0 8 0 pipepl 304 158 0 147 8 6 2 2 0 8 1 fdescpl 496 815 0 798 3 0 3 3 0 8 0 filepl 152 4774 0 4666 5 0 5 5 0 8 0 lockfpl 104 157 0 156 1 0 1 1 0 8 0 lockfspl 48 43 0 42 1 0 1 1 0 8 0 sessionpl 120 18 0 7 1 0 1 1 0 8 0 pgrppl 48 30 0 19 1 0 1 1 0 8 0 ucredpl 96 725 0 716 1 0 1 1 0 8 0 zombiepl 144 798 0 798 4 3 1 1 0 8 1 processpl 1008 831 0 798 7 2 5 5 0 8 0 procpl 632 2132 0 2089 4 0 4 4 0 8 0 sosppl 144 5 0 5 2 2 0 1 0 8 0 sockpl 400 1207 0 1182 9 6 3 4 0 8 0 mcl64k 65536 6 0 0 1 0 1 1 0 8 0 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl12k 12288 11 0 0 2 0 2 2 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 8 0 0 1 0 1 1 0 8 0 mcl4k 4096 12 0 0 2 0 2 2 0 8 0 mcl2k2 2112 3 0 0 1 0 1 1 0 8 0 mcl2k 2048 182 0 0 22 2 20 22 0 8 0 mtagpl 96 23 0 0 1 0 1 1 0 8 0 mbufpl 256 400 0 0 21 0 21 21 0 8 0 bufpl 280 4190 0 130 290 0 290 290 0 8 0 anonpl 16 99561 0 80852 114 22 92 92 0 124 16 amapchunkpl 152 5254 0 4955 34 17 17 26 0 158 4 amappl16 192 4171 0 3282 79 26 53 57 0 8 8 amappl15 184 9 0 7 1 0 1 1 0 8 0 amappl14 176 299 0 293 2 1 1 1 0 8 0 amappl13 168 31 0 27 1 0 1 1 0 8 0 amappl12 160 28 0 24 1 0 1 1 0 8 0 amappl11 152 51 0 36 1 0 1 1 0 8 0 amappl10 144 14 0 11 1 0 1 1 0 8 0 amappl9 136 660 0 656 1 0 1 1 0 8 0 amappl8 128 651 0 605 2 0 2 2 0 8 0 amappl7 120 117 0 105 1 0 1 1 0 8 0 amappl6 112 31 0 24 1 0 1 1 0 8 0 amappl5 104 719 0 702 1 0 1 1 0 8 0 amappl4 96 494 0 467 1 0 1 1 0 8 0 amappl3 88 438 0 429 1 0 1 1 0 8 0 amappl2 80 5561 0 5483 2 0 2 2 0 8 0 amappl1 72 33383 0 32900 23 13 10 18 0 8 0 amappl 80 2431 0 2345 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 49 0 8 1 0 1 1 0 8 0 uaddrrnd 24 823 0 801 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 823 0 801 1 0 1 1 0 8 0 vmmpekpl 168 10417 0 10383 2 0 2 2 0 8 0 vmmpepl 168 110962 0 108719 150 41 109 117 0 357 11 vmsppl 368 822 0 801 3 1 2 3 0 8 0 pdppl 4096 1653 0 1607 6 0 6 6 0 8 0 pvpl 32 294287 0 272286 257 43 214 214 0 265 36 pmappl 232 822 0 801 3 1 2 2 0 8 0 extentpl 40 53 0 36 1 0 1 1 0 8 0 phpool 112 279 0 18 8 0 8 8 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:398 panic(ffffffff8240e744) at panic+0x164 sys/kern/subr_prf.c:218 pool_cache_get(ffffffff828d47c8) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff828d47c8) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff828d47c8,1) at pool_get+0x91 sys/kern/subr_pool.c:572 m_get(1,1) at m_get+0x4c sys/kern/uipc_mbuf.c:250 m_getuio(ffff800020ed4bd8,1,2000,ffff800020ed4ca0) at m_getuio+0xbe sys/kern/uipc_socket.c:592 sosend(fffffd8063a47998,0,ffff800020ed4ca0,0,0,80) at sosend+0x54e sys/kern/uipc_socket.c:542 sendit(ffff800020eb2c70,a,ffff800020ed4d80,0,ffff800020ed4e60) at sendit+0x52b sys/kern/uipc_syscalls.c:657 sys_sendto(ffff800020eb2c70,ffff800020ed4e18,ffff800020ed4e60) at sys_sendto+0x80 sys/kern/uipc_syscalls.c:522 syscall(ffff800020ed4ee0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020ed4ee0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x5dbec82e240, count: -11 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp x86_ipi_db(ffff800020d70ff0) 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 __mp_lock(ffffffff8293cd60) at __mp_lock+0x127 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff8293cd60) at __mp_lock+0x127 sys/kern/kern_lock.c:147 __mp_acquire_count(ffffffff8293cd60,2) at __mp_acquire_count+0x51 sys/kern/kern_lock.c:227 mi_switch() at mi_switch+0x392 sys/kern/sched_bsd.c:435 sleep_finish(ffff800021f03d60,1) at sleep_finish+0x113 sys/kern/kern_synch.c:418 sleep_finish_all(ffff800021f03d60,1) at sleep_finish_all+0x32 sleep_finish_timeout sys/kern/kern_synch.c:447 [inline] sleep_finish_all(ffff800021f03d60,1) at sleep_finish_all+0x32 sys/kern/kern_synch.c:393 rwsleep(ffff800020eb2508,ffffffff82731aa0,120,ffffffff824058ef,0) at rwsleep+0x11b sys/kern/kern_synch.c:313 futex_wait(bccc70976d0,1,0,2) at futex_wait+0x13c sys/kern/sys_futex.c:254 sys_futex(ffff800020eb2508,ffff800021f03f00,ffff800021f03f50) at sys_futex+0x114 sys/kern/sys_futex.c:110 syscall(ffff800021f03fd0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800021f03fd0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xbcced44b5a0, count: 2 ddb{1}> trace x86_ipi_db(ffff800020d70ff0) 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 __mp_lock(ffffffff8293cd60) at __mp_lock+0x127 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff8293cd60) at __mp_lock+0x127 sys/kern/kern_lock.c:147 __mp_acquire_count(ffffffff8293cd60,2) at __mp_acquire_count+0x51 sys/kern/kern_lock.c:227 mi_switch() at mi_switch+0x392 sys/kern/sched_bsd.c:435 sleep_finish(ffff800021f03d60,1) at sleep_finish+0x113 sys/kern/kern_synch.c:418 sleep_finish_all(ffff800021f03d60,1) at sleep_finish_all+0x32 sleep_finish_timeout sys/kern/kern_synch.c:447 [inline] sleep_finish_all(ffff800021f03d60,1) at sleep_finish_all+0x32 sys/kern/kern_synch.c:393 rwsleep(ffff800020eb2508,ffffffff82731aa0,120,ffffffff824058ef,0) at rwsleep+0x11b sys/kern/kern_synch.c:313 futex_wait(bccc70976d0,1,0,2) at futex_wait+0x13c sys/kern/sys_futex.c:254 sys_futex(ffff800020eb2508,ffff800021f03f00,ffff800021f03f50) at sys_futex+0x114 sys/kern/sys_futex.c:110 syscall(ffff800021f03fd0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800021f03fd0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xbcced44b5a0, count: -13