*cpu0: uvm_fault(0xfffff2806cd963f0, 0x98, 0, 1) -> e ddb{1}> show kasan No such command ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x7e1539a0d690, count: -1 ddb{1}> show registers rdi 0 rsi 0 rbp 0xffff80002a28e310 rbx 0 rdx 0 rcx 0xffff800045ffd760 rax 0x34 r8 0xffff80002a28e240 r9 0xffff80002a28e0ac r10 0x5ba4c7f181854fe0 r11 0xa9270b82a63db682 r12 0 r13 0 r14 0xffff800045ffd760 r15 0 rip 0xffffffff826b93ee savectx+0xae cs 0x8 rflags 0x46 rsp 0xffff80002a28e290 ss 0x10 savectx+0xae: movl $0,%gs:0x688 ddb{1}> show proc PROC (syz-executor) tid=219940 pid=32836 tcnt=1 stat=onproc flags process=2 proc=0 runpri=50, usrpri=50, slppri=24, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff800045ffdc90,0xffff800045ffcd10 process=0xffff800045ff3030 user=0xffff80002a289000, vmspace=0xfffff2806e2101f8 estcpu=0, cpticks=8, pctcpu=0.6, user=0, sys=8, intr=0 ddb{1}> ps PID TID PPID UID S PRLAGS PFLAGS WAIT COMMAND 28175 46034 41315 0 2 0 0 syz-executor 28175 517023 41315 0 3 0 0x4000080 fsleep syz-executor 6912 360601 33556 0 2 0 0 syz-executor 6912 247726 33556 0 3 0 0x4000080 fsleep syz-executor 47321 189969 7152 0 2 0x100002 0 sh 1842 33020 67942 0 2 0 0 syz-executor 1842 400125 67942 0 7 0 0x4000000 syz-executor 35539 258712 73392 0 2 0x2 0 ndp 73392 161690 31696 0 3 0x100002 0x88 sigsusp sh 36566 27159 15769 0 2 0x2 0 ifconfig 15769 152474 67428 0 3 0x100002 0x88 sigsusp sh 26401 445911 34734 0 2 0x2 0 sh 34734 463663 32836 0 3 0x2 0x80 wait syz-executor 67942 327445 32836 0 3 0x2 0x80 nanoslp syz-executor 33556 298450 32836 0 3 0x2 0x80 nanoslp syz-executor 67428 96559 32836 0 3 0x2 0x80 wait syz-executor 41315 408431 32836 0 3 0x2 0x80 nanoslp syz-executor 31696 154589 32836 0 3 0x2 0x80 wait syz-executor 7152 16935 32836 0 3 0x2 0x80 wait syz-executor 35714 178523 32836 0 2 0x2 0 syz-executor *32836 219940 88301 0 7 0x2 0 syz-executor 88301 237679 63324 0 3 0x100002 0x88 sigsusp ksh 63324 434075 24701 0 3 0x10 0x88 kqread sshd-session 24701 236192 36699 0 3 0x12 0x80 kqread sshd-session 56770 212555 1 0 3 0x100003 0x80 ttyin getty 36699 240200 1 0 3 0 0x88 kqread sshd 51577 409183 32067 74 3 0x1100012 0x80 bpf pflogd 32067 98611 1 0 3 0 0x80 sbwait pflogd 80725 110811 38159 73 3 0x1100010 0x80 kqread syslogd 38159 406315 1 0 3 0x100002 0x80 sbwait syslogd 76113 392308 1 0 3 0x100000 0x80 kqread resolvd 18194 378081 51353 77 3 0x100012 0x80 kqread dhcpleased 20331 287401 51353 77 3 0x100012 0x80 kqread dhcpleased 51353 446044 1 0 3 0 0x80 kqread dhcpleased 50652 326071 0 0 3 0x14000 0x200 bored smr 37818 440115 0 0 2 0x14000 0x200 zerothread 58994 474617 0 0 3 0x14000 0x200 aiodoned aiodoned 9305 80499 0 0 3 0x14000 0x200 syncer update 12950 232493 0 0 3 0x14000 0x200 cleaner cleaner 2944 497524 0 0 3 0x14000 0x200 reaper reaper 46854 519805 0 0 3 0x14000 0x200 pgdaemon pagedaemon 1369 434290 0 0 3 0x14000 0x200 bored viomb 89673 204453 0 0 3 0x14000 0x40000200 acpi0 acpi0 42274 278702 0 0 3 0x14000 0x40000200 idle1 52223 476160 0 0 3 0x14000 0x200 bored softnet1 59131 437210 0 0 3 0x14000 0x200 bored softnet0 46541 451373 0 0 3 0x14000 0x200 smrbar systqmp 48729 483663 0 0 3 0x14000 0x200 bored systq 21975 43717 0 0 3 0x14000 0x200 tmoslp softclockmp 46820 80709 0 0 3 0x14000 0x40000200 tmoslp softclock 8445 140989 0 0 3 0x14000 0x40000200 idle0 1 330611 0 0 3 0x2 0x80 wait init 0 0 -1 0 3 0x10000 0x200 scheduler swapper ddb{1}> show all locks CPU 1: exclusive mutex /syzkaller/managers/multicore/kernel/sys/kern/kern_malloc.c:96 r = 0 (0xffffffff839120a8) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 mtx_enter+0x4b4 sys/kern/kern_lock.c:487 #2 free+0x9f sys/kern/kern_malloc.c:393 #3 dopselect+0xd42 sys/kern/sys_generic.c:732 #4 sys_pselect+0x25a sys/kern/sys_generic.c:593 #5 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #5 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 #6 Xsyscall+0x128 Process 1842 (syz-executor) thread 0xffff800045fefa08 (400125) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff83a7a440) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 syscall+0xaf4 mi_syscall sys/sys/syscall_mi.h:175 [inline] #1 syscall+0xaf4 sys/arch/amd64/amd64/trap.c:783 #2 Xsyscall+0x128 Process 35714 (syz-executor) thread 0xffff800045ffcd00 (178523) exclusive rrwlock inode r = 0 (0xfffff2806d7f77b0) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 #3 VOP_LOCK+0xbd sys/kern/vfs_vops.c:527 #4 ufs_ihashins+0x4f ufs_ihash sys/ufs/ufs/ufs_ihash.c:-1 [inline] #4 ufs_ihashins+0x4f sys/ufs/ufs/ufs_ihash.c:150 #5 ffs_vget+0x187 sys/ufs/ffs/ffs_vfsops.c:1232 #6 ffs_inode_alloc+0x279 sys/ufs/ffs/ffs_alloc.c:393 #7 ufs_mkdir+0xfc sys/ufs/ufs/ufs_vnops.c:1112 #8 VOP_MKDIR+0x101 sys/kern/vfs_vops.c:394 #9 domkdirat+0x179 sys/kern/vfs_syscalls.c:3063 #10 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] #10 syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 #11 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffff2806e077300) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 #3 VOP_LOCK+0xbd sys/kern/vfs_vops.c:527 #4 vn_lock+0xa4 sys/kern/vfs_vnops.c:576 #5 vfs_lookup+0x12b sys/kern/vfs_lookup.c:431 #6 namei+0x7c5 sys/kern/vfs_lookup.c:250 #7 domkdirat+0x8b sys/kern/vfs_syscalls.c:3048 #8 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] #8 syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 #9 Xsyscall+0x128 Process 46541 (systqmp) thread 0xffff800045ffe000 (451373) shared rwlock systqmp r = 0 (0xffffffff839acfd8) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 taskq_thread+0x12a sys/kern/kern_task.c:442 #2 proc_trampoline+0x10 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11052 12085K 12149K 166960K 12148 0 pcb 17 12K 12K 166960K 18 0 rtable 203 5K 6K 166960K 311 0 pf 34 17K 37K 166960K 46 0 ifaddr 39 6K 6K 166960K 42 0 ifgroup 55 2K 2K 166960K 55 0 sysctl 1 1K 9K 166960K 5 0 counters 70 37K 37K 166960K 70 0 ioctlops 0 0K 4K 166960K 1484 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1291 81K 81K 166960K 1362 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 1K 166960K 2 0 VM map 2 1K 1K 166960K 2 0 sem 2 0K 0K 166960K 2 0 dirhash 12 2K 2K 166960K 12 0 ACPI 1734 201K 291K 166960K 11964 0 file desc 19 69K 97K 166960K 131 0 proc 77 131K 180K 166960K 545 0 subproc 72 4K 4K 166960K 72 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 1 0 in_multi 84 5K 5K 166960K 85 0 ether_multi 1 0K 0K 166960K 1 0 mrt 0 0K 0K 166960K 1 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 31 148K 148K 166960K 31 0 exec 0 0K 1K 166960K 383 0 fusefs mount 1 32K 32K 166960K 1 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 213 162K 167K 166960K 3028 0 UVM aobj 4 2K 2K 166960K 4 0 pinsyscall 45 90K 108K 166960K 1297 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 NDP 25 1K 1K 166960K 25 0 temp 33 9114K 9120K 166960K 3891 0 kqueue 13 20K 20K 166960K 25 0 SYN cache 2 16K 16K 166960K 2 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 28 0 0 1 0 1 1 0 8 0 rtpcb 120 31 0 28 1 0 1 1 0 8 0 rtentry 176 98 0 5 5 0 5 5 0 8 0 unpcb 144 43 0 24 1 0 1 1 0 8 0 syncache 336 4 0 4 1 0 1 1 0 8 1 tcpcb 736 9 0 5 1 0 1 1 0 8 0 arp 136 17 0 2 1 0 1 1 0 8 0 inpcb 328 69 0 61 1 0 1 1 0 8 0 nd6 152 17 0 0 1 0 1 1 0 8 0 kcovpl 48 8 0 0 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 15 0 0 1 0 1 1 0 8 0 pfstkey 128 15 0 0 1 0 1 1 0 8 0 pfstate 448 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 256 394 0 0 25 0 25 25 0 8 0 art_table 40 395 0 0 4 0 4 4 0 8 0 art_node 32 98 0 7 1 0 1 1 0 8 0 shmpl 112 1 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1567 0 102 92 0 92 92 0 8 0 ffsino 296 1567 0 102 113 0 113 113 0 8 0 nchpl 144 1768 0 76 63 0 63 63 0 8 0 vnodes 216 1658 0 0 93 0 93 93 0 8 0 namei 1024 5418 0 5417 2 0 2 2 0 8 1 percpumem 16 51 0 0 1 0 1 1 0 8 0 kstatmem 264 27 0 0 2 0 2 2 0 8 0 scxspl 216 6157 0 6157 4 2 2 3 1 8 2 plimitpl 152 30 0 12 1 0 1 1 0 8 0 sigapl 424 457 0 408 7 0 7 7 0 8 1 knotepl 120 52 0 0 2 0 2 2 0 8 0 kqueuepl 224 21 0 12 1 0 1 1 0 8 0 pipepl 344 129 0 102 3 0 3 3 0 8 0 fdescpl 528 441 0 408 3 0 3 3 0 8 0 filepl 160 1575 0 1362 10 0 10 10 0 8 0 lockfpl 104 12 0 10 1 0 1 1 0 8 0 lockfspl 48 7 0 5 1 0 1 1 0 8 0 sessionpl 144 24 0 15 1 0 1 1 0 8 0 pgrppl 48 32 0 15 1 0 1 1 0 8 0 ucredpl 104 87 0 74 1 0 1 1 0 8 0 zombiepl 144 408 0 408 1 0 1 1 0 8 1 processpl 1232 457 0 408 5 0 5 5 0 8 0 procpl 664 470 0 418 5 0 5 5 0 8 0 sockpl 752 143 0 113 4 0 4 4 0 8 0 mcl64k 65536 1 0 0 1 0 1 1 0 8 0 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 1 0 0 1 0 1 1 0 8 0 mcl4k 4096 122 0 0 16 0 16 16 0 8 0 mcl2k 2048 24 0 0 3 0 3 3 0 8 0 mextrefs 64 26 0 0 1 0 1 1 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 203 0 0 13 0 13 13 0 8 0 bufpl 272 2284 0 105 146 0 146 146 0 8 0 anonpl 32 3830 0 0 31 0 31 31 0 247 0 amapchunkpl 152 8396 0 8002 17 0 17 17 0 158 1 amappl16 200 1802 0 1787 5 0 5 5 0 8 4 amappl15 192 9 0 8 1 0 1 1 0 8 0 amappl14 184 432 0 427 1 0 1 1 0 8 0 amappl13 176 122 0 108 1 0 1 1 0 8 0 amappl12 168 690 0 660 2 0 2 2 0 8 0 amappl11 160 3 0 3 1 0 1 1 0 8 1 amappl10 152 65 0 51 1 0 1 1 0 8 0 amappl9 144 277 0 277 1 0 1 1 0 8 1 amappl8 136 101 0 98 1 0 1 1 0 8 0 amappl7 128 145 0 131 1 0 1 1 0 8 0 amappl6 120 155 0 149 1 0 1 1 0 8 0 amappl5 112 126 0 116 1 0 1 1 0 8 0 amappl4 104 294 0 275 1 0 1 1 0 8 0 amappl3 96 1421 0 1338 3 0 3 3 0 8 0 amappl2 88 570 0 496 2 0 2 2 0 8 0 amappl1 80 10399 0 9760 15 0 15 15 0 8 0 amappl 88 2303 0 2169 4 0 4 4 0 92 0 uvmvnodes 80 99 0 0 3 0 3 3 0 8 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 72 3 0 0 1 0 1 1 0 8 0 uaddrrnd 24 441 0 408 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 441 0 408 1 0 1 1 0 8 0 vmmpekpl 168 5693 0 5663 2 0 2 2 0 8 0 vmmpepl 168 37885 0 36055 86 0 86 86 0 357 3 vmsppl 488 440 0 408 5 0 5 5 0 8 0 rwobjpl 80 14527 0 13470 25 0 25 25 0 8 2 pdppl 4096 889 0 816 99 12 87 87 0 8 14 pvpl 32 9060 0 0 74 0 74 74 0 265 0 pmappl 256 440 0 408 3 0 3 3 0 8 0 extentpl 40 46 0 28 1 0 1 1 0 8 0 phpool 112 415 0 15 12 0 12 12 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff83984ff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 x86_bus_space_io_write_1(3f8,0,6c) at x86_bus_space_io_write_1+0x40 sys/arch/amd64/amd64/bus_space.c:790 comcnputc(800,6c) at comcnputc+0x1ab bus_space_barrier sys/dev/ic/com.c:-1 [inline] comcnputc(800,6c) at comcnputc+0x1ab sys/dev/ic/com.c:1268 cnputc(6c) at cnputc+0x67 sys/dev/cons.c:218 db_putchar(6c) at db_putchar+0x36d sys/ddb/db_output.c:155 kprintf() at kprintf+0x223 sys/kern/subr_prf.c:723 db_printf(ffffffff835480cf) at db_printf+0x9b sys/kern/subr_prf.c:-1 db_ktrap(6,0,ffff8000373a3540) at db_ktrap+0xe3 db_printtrap sys/arch/amd64/amd64/db_interface.c:99 [inline] db_ktrap(6,0,ffff8000373a3540) at db_ktrap+0xe3 sys/arch/amd64/amd64/db_interface.c:128 kerntrap(ffff8000373a3540) at kerntrap+0x243 sys/arch/amd64/amd64/trap.c:519 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b dovutimens(ffff800045fefa08,fffff2806ce2abd0,ffff8000373a3720) at dovutimens+0x368 sys/kern/vfs_syscalls.c:2691 sys_futimes(ffff800045fefa08,ffff8000373a3870,ffff8000373a37c0) at sys_futimes+0x208 sys/kern/vfs_syscalls.c:2733 end trace frame: 0xffff8000373a3860, count: 0 ddb{0}> trace x86_ipi_db(ffffffff83984ff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 x86_bus_space_io_write_1(3f8,0,6c) at x86_bus_space_io_write_1+0x40 sys/arch/amd64/amd64/bus_space.c:790 comcnputc(800,6c) at comcnputc+0x1ab bus_space_barrier sys/dev/ic/com.c:-1 [inline] comcnputc(800,6c) at comcnputc+0x1ab sys/dev/ic/com.c:1268 cnputc(6c) at cnputc+0x67 sys/dev/cons.c:218 db_putchar(6c) at db_putchar+0x36d sys/ddb/db_output.c:155 kprintf() at kprintf+0x223 sys/kern/subr_prf.c:723 db_printf(ffffffff835480cf) at db_printf+0x9b sys/kern/subr_prf.c:-1 db_ktrap(6,0,ffff8000373a3540) at db_ktrap+0xe3 db_printtrap sys/arch/amd64/amd64/db_interface.c:99 [inline] db_ktrap(6,0,ffff8000373a3540) at db_ktrap+0xe3 sys/arch/amd64/amd64/db_interface.c:128 kerntrap(ffff8000373a3540) at kerntrap+0x243 sys/arch/amd64/amd64/trap.c:519 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b dovutimens(ffff800045fefa08,fffff2806ce2abd0,ffff8000373a3720) at dovutimens+0x368 sys/kern/vfs_syscalls.c:2691 sys_futimes(ffff800045fefa08,ffff8000373a3870,ffff8000373a37c0) at sys_futimes+0x208 sys/kern/vfs_syscalls.c:2733 syscall(ffff8000373a3870) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff8000373a3870) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x51e20515960, count: -16 ddb{0}> machine ddbcpu 1 Stopped at savectx+0xae: movl $0,%gs:0x688 savectx() at savectx+0xae end of kernel end trace frame: 0x7e1539a0d690, count: 14 ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x7e1539a0d690, count: -1