witness: lock order reversal: 1st 0xfffffd807001d068 fdlock (&newfdp->fd_fd.fd_lock) 2nd 0xfffffd806d6e62c8 inode (&ip->i_lock) lock order data w2 -> w1 missing lock order data w1 -> w2 missing Stopped at db_enter+0x18: addq $0x8,%rsp ddb{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic the kernel did not panic ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 witness_checkorder(fffffd806d6e62c8,9,0) at witness_checkorder+0x108b rw_enter(fffffd806d6e62b8,1) at rw_enter+0xd4 rrw_enter(fffffd806d6e62b8,1) at rrw_enter+0x88 sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd806d8c9690,2001) at VOP_LOCK+0x4b sys/kern/vfs_vops.c:614 vn_lock(fffffd806d8c9690,2001) at vn_lock+0x6c sys/kern/vfs_vnops.c:575 vget(fffffd806d8c9690,2001) at vget+0x1c6 sys/kern/vfs_subr.c:671 ktrwriteraw(ffff8000211fed20,fffffd806d8c9690,fffffd807f7b76c0,ffff8000212697a0,ffff800021269780) at ktrwriteraw+0x138 sys/kern/kern_ktrace.c:659 ktrstruct(ffff8000211fed20,ffffffff823b3070,ffff800021269888,8) at ktrstruct+0x169 ktrwrite2 sys/kern/kern_ktrace.c:627 [inline] ktrstruct(ffff8000211fed20,ffffffff823b3070,ffff800021269888,8) at ktrstruct+0x169 sys/kern/kern_ktrace.c:311 sys_socketpair(ffff8000211fed20,ffff8000212698f8,ffff800021269940) at sys_socketpair+0x3ed sys/kern/uipc_syscalls.c:470 syscall(ffff8000212699c0) at syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000212699c0) at syscall+0x4a1 sys/arch/amd64/amd64/trap.c:590 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x2c811fa72b0, count: -12 ddb{1}> show registers rdi 0x3 rsi 0xffffffff826ee900 __sancov_gen_cov_switch_values.134 rbp 0xffff8000212693c0 rbx 0x3 rdx 0x8b rcx 0x3 rax 0x1 r8 0xffffffff813b9c91 witness_checkorder+0x1061 r9 0x5 r10 0x4f21151a3a6e42c3 r11 0x4ea7689cdf50b67a r12 0 r13 0xfffffd806d6e62c8 r14 0 r15 0xfffffd8002cf0600 rip 0xffffffff8153d808 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000212693b0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor7266) pid=511273 stat=onproc flags process=0 proc=4000001 pri=17, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000211ff260,0xffffffff8279c450 process=0xffff8000212261d0 user=0xffff800021264000, vmspace=0xfffffd80084ae730 estcpu=2, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 31191 340983 28270 0 7 0 syz-executor7266 *31191 511273 28270 0 7 0x4000001 syz-executor7266 10445 259829 89945 0 3 0x80 nanoslp syz-executor7266 10445 467822 89945 0 3 0x4000080 fifow syz-executor7266 10445 207946 89945 0 3 0x4000080 fsleep syz-executor7266 89945 111322 57427 0 3 0x80 nanoslp syz-executor7266 28270 345321 57427 0 3 0x80 nanoslp syz-executor7266 57427 302433 3447 0 3 0x82 nanoslp syz-executor7266 3447 226352 88274 0 3 0x10008a sigsusp ksh 88274 174250 81820 0 3 0x92 select sshd 91331 54673 1 0 3 0x100083 ttyin getty 81820 248159 1 0 3 0x80 select sshd 63828 385716 13728 74 3 0x100092 bpf pflogd 13728 230122 1 0 3 0x80 netio pflogd 36725 440377 61430 73 3 0x100090 kqread syslogd 61430 92776 1 0 3 0x100082 netio syslogd 45707 70131 1 77 3 0x100090 poll dhclient 23160 358963 1 0 3 0x80 poll dhclient 74959 115946 0 0 3 0x14200 bored smr 88434 347845 0 0 3 0x14200 pgzero zerothread 4540 500295 0 0 3 0x14200 aiodoned aiodoned 86655 398511 0 0 3 0x14200 syncer update 96944 165617 0 0 3 0x14200 cleaner cleaner 90196 168795 0 0 3 0x14200 reaper reaper 22264 190850 0 0 3 0x14200 pgdaemon pagedaemon 54267 223785 0 0 3 0x14200 bored crynlk 10973 67692 0 0 3 0x14200 bored crypto 7207 110567 0 0 3 0x14200 bored viomb 96976 85760 0 0 3 0x40014200 acpi0 acpi0 79350 109306 0 0 3 0x40014200 idle1 48581 360594 0 0 3 0x14200 bored softnet 56492 64775 0 0 3 0x14200 bored systqmp 7968 73942 0 0 3 0x14200 bored systq 73106 80633 0 0 3 0x40014200 bored softclock 65918 107480 0 0 3 0x40014200 idle0 1 267607 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 31191 (syz-executor7266) thread 0xffff8000211fed20 (511273) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff828d8de8) #0 witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4b0 sys/kern/subr_witness.c:1182 #1 ktrstruct+0xee #2 sys_socketpair+0x3ed sys/kern/uipc_syscalls.c:470 #3 syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] #3 syscall+0x4a1 sys/arch/amd64/amd64/trap.c:590 #4 Xsyscall+0x128 exclusive rwlock fdlock r = 0 (0xfffffd807001d068) #0 witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4b0 sys/kern/subr_witness.c:1182 #1 sys_socketpair+0x219 #2 syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] #2 syscall+0x4a1 sys/arch/amd64/amd64/trap.c:590 #3 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9475 6411K 6412K 78643K 10565 0 pcb 13 8K 8K 78643K 13 0 rtable 61 2K 2K 78643K 119 0 ifaddr 29 8K 8K 78643K 30 0 counters 40 33K 33K 78643K 40 0 ioctlops 0 0K 4K 78643K 1467 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 1 0 vnodes 1184 74K 75K 78643K 1191 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 2 0K 0K 78643K 2 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12598 0 file desc 1 0K 0K 78643K 1 0 proc 59 63K 71K 78643K 357 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 in_multi 11 0K 0K 78643K 11 0 ether_multi 1 0K 0K 78643K 1 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 2K 78643K 300 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 100 4K 5K 78643K 1437 0 UVM aobj 3 2K 2K 78643K 3 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 NDP 4 0K 0K 78643K 4 0 temp 23 3965K 4029K 78643K 1685 0 kqueue 2 2K 2K 78643K 2 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 2 0 0 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 120 15 0 13 1 0 1 1 0 8 0 rtentry 112 23 0 1 1 0 1 1 0 8 0 unpcb 120 45 0 29 1 0 1 1 0 8 0 syncache 296 5 0 5 2 1 1 1 0 8 1 tcpcb 736 8 0 5 1 0 1 1 0 8 0 inpcb 304 28 0 23 1 0 1 1 0 8 0 pfosfp 40 1428 0 1005 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 9 0 2 1 0 1 1 0 8 0 pfstkey 112 9 0 2 1 0 1 1 0 8 0 pfstate 320 9 0 2 1 0 1 1 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 97 0 0 7 0 7 7 0 8 0 art_table 32 98 0 0 1 0 1 1 0 8 0 art_node 16 22 0 2 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1415 0 25 87 0 87 87 0 8 0 ffsino 272 1415 0 25 93 0 93 93 0 8 0 nchpl 144 1602 0 51 58 0 58 58 0 8 0 uvmvnodes 72 1425 0 0 26 0 26 26 0 8 0 vnodes 224 1425 0 0 84 0 84 84 0 8 0 namei 1024 3819 0 3819 2 1 1 1 0 8 1 percpumem 16 31 0 0 1 0 1 1 0 8 0 scxspl 216 3700 0 3700 11 10 1 8 0 8 1 plimitpl 152 14 0 8 1 0 1 1 0 8 0 sigapl 424 227 0 194 4 0 4 4 0 8 0 futexpl 56 8 0 7 1 0 1 1 0 8 0 knotepl 112 5 0 0 1 0 1 1 0 8 0 kqueuepl 168 1 0 0 1 0 1 1 0 8 0 pipepl 336 64 0 60 2 1 1 1 0 8 0 fdescpl 496 211 0 194 3 0 3 3 0 8 0 filepl 152 974 0 921 3 0 3 3 0 8 0 lockfpl 104 5 0 4 1 0 1 1 0 8 0 lockfspl 48 3 0 2 1 0 1 1 0 8 0 sessionpl 144 18 0 9 1 0 1 1 0 8 0 pgrppl 48 18 0 9 1 0 1 1 0 8 0 ucredpl 96 62 0 53 1 0 1 1 0 8 0 zombiepl 144 194 0 194 2 1 1 1 0 8 1 processpl 1080 227 0 194 3 0 3 3 0 8 0 procpl 672 236 0 200 4 0 4 4 0 8 0 sockpl 432 88 0 65 4 1 3 3 0 8 0 mcl4k 4096 3 0 0 1 0 1 1 0 8 0 mcl2k 2048 91 0 0 10 0 10 10 0 8 0 mtagpl 96 1 0 0 1 0 1 1 0 8 0 mbufpl 256 97 0 0 6 0 6 6 0 8 0 bufpl 280 2025 0 90 139 0 139 139 0 8 0 anonpl 24 30202 0 27664 19 3 16 16 0 186 0 amapchunkpl 152 2760 0 2574 9 1 8 8 0 158 0 amappl16 200 38 0 34 2 1 1 1 0 8 0 amappl15 192 51 0 46 1 0 1 1 0 8 0 amappl13 176 14 0 13 2 1 1 1 0 8 0 amappl12 168 24 0 21 1 0 1 1 0 8 0 amappl11 160 39 0 28 1 0 1 1 0 8 0 amappl10 152 6 0 2 1 0 1 1 0 8 0 amappl9 144 241 0 241 2 2 0 1 0 8 0 amappl8 136 241 0 235 1 0 1 1 0 8 0 amappl7 128 36 0 33 1 0 1 1 0 8 0 amappl6 120 82 0 73 1 0 1 1 0 8 0 amappl5 112 129 0 119 1 0 1 1 0 8 0 amappl4 104 475 0 452 1 0 1 1 0 8 0 amappl3 96 37 0 31 1 0 1 1 0 8 0 amappl2 88 346 0 307 1 0 1 1 0 8 0 amappl1 80 6732 0 6339 11 2 9 9 0 8 0 amappl 88 1230 0 1148 2 0 2 2 0 92 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 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 2 0 0 1 0 1 1 0 8 0 uaddrrnd 24 211 0 194 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 211 0 194 1 0 1 1 0 8 0 vmmpekpl 168 5473 0 5456 1 0 1 1 0 8 0 vmmpepl 168 20056 0 19092 47 4 43 43 0 357 1 vmsppl 368 210 0 194 2 0 2 2 0 8 0 rwobjpl 56 6220 0 5684 10 2 8 8 0 8 0 pdppl 4096 429 0 388 59 18 41 41 0 8 0 pvpl 32 98921 0 94409 42 5 37 37 0 265 0 pmappl 232 210 0 194 1 0 1 1 0 8 0 extentpl 40 58 0 40 1 0 1 1 0 8 0 phpool 112 279 0 23 8 0 8 8 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp ddb{0}> trace x86_ipi_db(ffffffff826c9ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:352 x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23 __mp_lock(ffffffff828d8be0) at __mp_lock+0x129 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff828d8be0) at __mp_lock+0x129 sys/kern/kern_lock.c:147 softintr_dispatch(0) at softintr_dispatch+0x4e sys/arch/amd64/amd64/softintr.c:90 Xsoftclock() at Xsoftclock+0x1f end of kernel end trace frame: 0x7f7ffffd9ba0, count: -6 ddb{0}> machine ddbcpu 1 Stopped at db_enter+0x18: addq $0x8,%rsp ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 witness_checkorder(fffffd806d6e62c8,9,0) at witness_checkorder+0x108b rw_enter(fffffd806d6e62b8,1) at rw_enter+0xd4 rrw_enter(fffffd806d6e62b8,1) at rrw_enter+0x88 sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd806d8c9690,2001) at VOP_LOCK+0x4b sys/kern/vfs_vops.c:614 vn_lock(fffffd806d8c9690,2001) at vn_lock+0x6c sys/kern/vfs_vnops.c:575 vget(fffffd806d8c9690,2001) at vget+0x1c6 sys/kern/vfs_subr.c:671 ktrwriteraw(ffff8000211fed20,fffffd806d8c9690,fffffd807f7b76c0,ffff8000212697a0,ffff800021269780) at ktrwriteraw+0x138 sys/kern/kern_ktrace.c:659 ktrstruct(ffff8000211fed20,ffffffff823b3070,ffff800021269888,8) at ktrstruct+0x169 ktrwrite2 sys/kern/kern_ktrace.c:627 [inline] ktrstruct(ffff8000211fed20,ffffffff823b3070,ffff800021269888,8) at ktrstruct+0x169 sys/kern/kern_ktrace.c:311 sys_socketpair(ffff8000211fed20,ffff8000212698f8,ffff800021269940) at sys_socketpair+0x3ed sys/kern/uipc_syscalls.c:470 syscall(ffff8000212699c0) at syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000212699c0) at syscall+0x4a1 sys/arch/amd64/amd64/trap.c:590 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x2c811fa72b0, count: -12 ddb{1}>