panic: kernel diagnostic assertion "ISSET(p->p_flag, P_SUSPSIG | P_SUSPSINGLE) == 0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_sig.c", line 1603 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 372774 61768 0 0x8000 0x8000000 1 syz-executor *301132 61768 0 0x8000 0xc000000 0 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834d2f2d) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff8350dd6d,ffffffff834750c4,643,ffffffff83457140) at __assert+0x29 sys/kern/subr_prf.c:-1 process_stop(ffff800045fe7568,8000000,1) at process_stop+0x3fe cursig(ffff80002a22b240,ffff80002a30e338,0) at cursig+0x509 x86_atomic_setbits_u32 sys/arch/amd64/compile/SYZKALLER/obj/machine/atomic.h:-1 [inline] cursig(ffff80002a22b240,ffff80002a30e338,0) at cursig+0x509 sys/kern/kern_sig.c:1446 userret(ffff80002a22b240) at userret+0x203 sys/kern/kern_sig.c:2208 syscall(ffff80002a30e470) at syscall+0x9ce mi_syscall_return sys/sys/syscall_mi.h:203 [inline] syscall(ffff80002a30e470) at syscall+0x9ce sys/arch/amd64/amd64/trap.c:812 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xc273591d780, count: 7 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 *cpu0: kernel diagnostic assertion "ISSET(p->p_flag, P_SUSPSIG | P_SUSPSINGLE) == 0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_sig.c", line 1603 ddb{0}> show kasan No such command ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834d2f2d) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff8350dd6d,ffffffff834750c4,643,ffffffff83457140) at __assert+0x29 sys/kern/subr_prf.c:-1 process_stop(ffff800045fe7568,8000000,1) at process_stop+0x3fe cursig(ffff80002a22b240,ffff80002a30e338,0) at cursig+0x509 x86_atomic_setbits_u32 sys/arch/amd64/compile/SYZKALLER/obj/machine/atomic.h:-1 [inline] cursig(ffff80002a22b240,ffff80002a30e338,0) at cursig+0x509 sys/kern/kern_sig.c:1446 userret(ffff80002a22b240) at userret+0x203 sys/kern/kern_sig.c:2208 syscall(ffff80002a30e470) at syscall+0x9ce mi_syscall_return sys/sys/syscall_mi.h:203 [inline] syscall(ffff80002a30e470) at syscall+0x9ce sys/arch/amd64/amd64/trap.c:812 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xc273591d780, count: -8 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff80002a30e150 rbx 0xffffffff8396fe0f cpu_info_full_primary+0x2e0f rdx 0 rcx 0xffff80002a22b240 rax 0xffffffff8396eff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0xfed285242c3b12f r11 0x623655928e6f1bdc r12 0xffffffff8396fc10 cpu_info_full_primary+0x2c10 r13 0 r14 0 r15 0x1 rip 0xffffffff82bd27e5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002a30e140 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=301132 pid=61768 tcnt=3 stat=onproc flags process=8000 proc=c000000 runpri=32, usrpri=50, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=2 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002a22a7e0,0xffff800045fe8568 process=0xffff800045fe7568 user=0xffff80002a309000, vmspace=0xfffff0006c942208 estcpu=36, cpticks=0, pctcpu=0.0, user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S PRLAGS PFLAGS WAIT COMMAND 61768 372774 62032 0 7 0x8000 0x8000000 syz-executor *61768 301132 62032 0 7 0x8000 0xc000000 syz-executor 61768 45470 62032 0 4 0x8000 0xc000000 syz-executor 52289 337670 82851 0 2 0 0 syz-executor 10947 379919 816 0 2 0 0 syz-executor 97442 433837 65271 0 2 0 0 syz-executor 97442 267039 65271 0 3 0 0x4000080 fsleep syz-executor 31635 485655 12578 0 2 0x100002 0 sh 919 111588 90793 0 2 0x100002 0 ndp 90793 370260 58092 0 3 0x100002 0x88 sigsusp sh 12578 445837 95441 0 3 0x2 0x80 wait syz-executor 82851 123908 95441 0 3 0x2 0x80 nanoslp syz-executor 28454 459257 72091 0 3 0 0x80 nanoslp syz-executor 28454 383143 72091 0 3 0 0x4000080 fifow syz-executor 58092 123314 95441 0 3 0x2 0x80 wait syz-executor 33334 410493 95441 0 3 0x2 0x80 piperd syz-executor 816 70758 95441 0 3 0x2 0x80 nanoslp syz-executor 65271 165960 95441 0 3 0x2 0x80 nanoslp syz-executor 62032 19412 95441 0 3 0x2 0x80 nanoslp syz-executor 73648 281045 1 0 3 0x100003 0x80 ttyin getty 72091 5994 95441 0 3 0x2 0x80 nanoslp syz-executor 95441 266762 16977 0 2 0x2 0 syz-executor 16977 308055 70859 0 3 0x100002 0x88 sigsusp ksh 70859 210777 93641 0 3 0x10 0x88 kqread sshd-session 93641 34561 64781 0 3 0x12 0x80 kqread sshd-session 64781 252009 1 0 3 0 0x88 kqread sshd 96826 60641 41557 74 3 0x1100012 0x80 bpf pflogd 41557 279632 1 0 3 0 0x80 sbwait pflogd 7517 258687 84189 73 3 0x1100010 0x80 kqread syslogd 84189 244153 1 0 3 0x100002 0x80 sbwait syslogd 61082 498622 1 0 3 0x100000 0x80 kqread resolvd 74609 257402 8839 77 3 0x100012 0x80 kqread dhcpleased 20414 269863 8839 77 3 0x100012 0x80 kqread dhcpleased 8839 35164 1 0 3 0 0x80 kqread dhcpleased 16156 425063 0 0 3 0x14000 0x200 bored smr 37372 244711 0 0 3 0x14000 0x200 pgzero zerothread 39133 448407 0 0 3 0x14000 0x200 aiodoned aiodoned 567 487925 0 0 3 0x14000 0x200 syncer update 84510 162840 0 0 3 0x14000 0x200 cleaner cleaner 32314 447971 0 0 3 0x14000 0x200 reaper reaper 52837 474198 0 0 3 0x14000 0x200 pgdaemon pagedaemon 92475 5714 0 0 3 0x14000 0x200 bored viomb 3331 336840 0 0 3 0x14000 0x40000200 acpi0 acpi0 47163 370979 0 0 3 0x14000 0x40000200 idle1 32356 421982 0 0 3 0x14000 0x200 bored softnet1 70932 93945 0 0 3 0x14000 0x200 bored softnet0 10211 483777 0 0 3 0x14000 0x200 smrbar systqmp 14194 51281 0 0 3 0x14000 0x200 bored systq 22918 185161 0 0 3 0x14000 0x200 tmoslp softclockmp 23188 344032 0 0 3 0x14000 0x40000200 tmoslp softclock 39713 70979 0 0 3 0x14000 0x40000200 idle0 1 424585 0 0 4 0x40000002 0x8000080 init 0 0 -1 0 3 0x10010000 0x200 scheduler swapper ddb{0}> show all locks CPU 0: exclusive mutex &sched_lock r = 0 (0xffffffff83ac43d8) #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 cursig+0x4ee sys/kern/kern_sig.c:1445 #3 userret+0x203 sys/kern/kern_sig.c:2208 #4 syscall+0x9ce mi_syscall_return sys/sys/syscall_mi.h:203 [inline] #4 syscall+0x9ce sys/arch/amd64/amd64/trap.c:812 #5 Xsyscall+0x128 exclusive mutex &pr->ps_mtx r = 0 (0xffff800045fe7680) #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 cursig+0x4c2 sys/kern/kern_sig.c:1441 #3 userret+0x203 sys/kern/kern_sig.c:2208 #4 syscall+0x9ce mi_syscall_return sys/sys/syscall_mi.h:203 [inline] #4 syscall+0x9ce sys/arch/amd64/amd64/trap.c:812 #5 Xsyscall+0x128 Process 10211 (systqmp) thread 0xffff800045ffe7c8 (483777) shared rwlock systqmp r = 0 (0xffffffff839402c8) #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{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11071 12090K 12219K 166960K 12383 0 pcb 18 12K 12K 166960K 55 0 rtable 235 16K 17K 166960K 1061 0 pf 38 18K 22K 166960K 112 0 ifaddr 40 7K 7K 166960K 139 0 ifgroup 59 2K 2K 166960K 156 0 sysctl 4 1K 9K 166960K 10 0 counters 72 37K 37K 166960K 192 0 ioctlops 0 0K 4K 166960K 1572 0 iov 0 0K 20K 166960K 13 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1295 81K 82K 166960K 1697 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 5 0 VM map 2 1K 1K 166960K 2 0 sem 19 1K 1K 166960K 20 0 dirhash 12 2K 2K 166960K 12 0 ACPI 1734 201K 291K 166960K 11964 0 file desc 18 65K 93K 166960K 626 0 sigio 0 0K 0K 166960K 1 0 proc 72 115K 180K 166960K 1174 0 subproc 72 4K 4K 166960K 270 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 150 0 in_multi 87 5K 6K 166960K 336 0 ether_multi 1 0K 0K 166960K 4 0 mrt 1 0K 0K 166960K 13 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 97 440K 440K 166960K 97 0 exec 0 0K 1K 166960K 712 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 223 170K 181K 166960K 6575 0 UVM aobj 9 2K 2K 166960K 11 0 pinsyscall 44 88K 102K 166960K 2368 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 3 0 NDP 23 1K 2K 166960K 96 0 temp 39 9123K 9151K 166960K 15832 0 kqueue 13 20K 28K 166960K 59 0 SYN cache 2 16K 16K 166960K 2 0 ddb{0}> 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 89 0 85 1 0 1 1 0 8 0 rtentry 176 348 0 251 6 0 6 6 0 8 1 unpcb 144 181 0 161 3 1 2 2 0 8 1 syncache 336 4 0 4 1 1 0 1 0 8 0 tcpcb 736 118 0 114 4 0 4 4 0 8 3 arp 136 60 0 44 1 0 1 1 0 8 0 inpcb 328 365 0 354 4 0 4 4 0 8 3 nd6 152 88 0 67 1 0 1 1 0 8 0 pkpcb 40 1 0 1 1 0 1 1 0 8 1 kcovpl 48 30 0 22 1 0 1 1 0 8 0 ppxss 1192 37 0 37 1 0 1 1 0 8 1 pppxif 1576 1 0 1 1 0 1 1 0 8 1 pfstscr 40 6 0 4 1 0 1 1 0 8 0 pffrag 232 3 0 0 1 0 1 1 0 482 0 pffrnode 88 3 0 0 1 0 1 1 0 8 0 pffrent 40 3 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 pfrktable 1344 4 0 4 1 0 1 1 0 8 1 pfstlim 224 1 0 1 1 0 1 1 0 8 1 pfanchor 1288 1 0 1 1 0 1 1 0 8 1 pfstitem 24 48 0 0 1 0 1 1 0 8 0 pfstkey 128 52 0 4 2 0 2 2 0 8 0 pfstate 448 49 0 2 6 0 6 6 0 8 0 pfrule 1360 26 0 20 2 0 2 2 0 8 0 rttmr 136 1 0 1 1 0 1 1 0 8 1 art_heap8 4096 3 0 1 3 0 3 3 0 8 1 art_heap4 256 1438 0 987 31 0 31 31 0 8 2 art_table 40 1441 0 988 5 0 5 5 0 8 0 art_node 32 347 0 256 1 0 1 1 0 8 0 sysvmsgpl 40 2 0 1 1 0 1 1 0 8 0 semupl 112 2 0 2 1 0 1 1 0 8 1 semapl 72 18 0 1 1 0 1 1 0 8 0 shmpl 120 8 0 2 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1934 0 417 95 0 95 95 0 8 0 ffsino 296 1934 0 417 117 0 117 117 0 8 0 nchpl 144 2377 0 596 66 0 66 66 0 8 0 rtmask 32 2 0 2 1 1 0 1 0 8 0 vnodes 216 2275 0 0 127 0 127 127 0 8 0 namei 1024 10973 0 10973 3 2 1 2 0 8 1 percpumem 16 112 0 60 1 0 1 1 0 8 0 pfiaddrpl 120 1 0 1 1 0 1 1 0 8 1 kstatmem 264 81 0 50 3 0 3 3 0 8 0 scxspl 216 8017 0 8017 11 3 8 8 1 8 8 plimitpl 152 91 0 73 1 0 1 1 0 8 0 sigapl 424 909 0 861 7 1 6 7 0 8 0 knotepl 120 618 0 0 19 0 19 19 0 8 0 kqueuepl 224 117 0 108 3 2 1 3 0 8 0 pipepl 344 207 0 179 3 0 3 3 0 8 0 fdescpl 528 893 0 861 3 0 3 3 0 8 0 filepl 160 3691 0 3472 13 0 13 13 0 8 2 lockfpl 104 104 0 101 1 0 1 1 0 8 0 lockfspl 48 44 0 41 1 0 1 1 0 8 0 sessionpl 144 50 0 41 1 0 1 1 0 8 0 pgrppl 48 87 0 69 1 0 1 1 0 8 0 ucredpl 104 457 0 444 1 0 1 1 0 8 0 zombiepl 144 861 0 861 1 0 1 1 0 8 1 processpl 1240 909 0 861 5 1 4 5 0 8 0 procpl 664 1240 0 1188 6 0 6 6 0 8 0 sockpl 752 772 0 737 9 1 8 8 0 8 3 mcl64k 65536 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 120 0 0 15 0 15 15 0 8 0 mcl2k 2048 26 0 0 4 0 4 4 0 8 0 mextrefs 64 25 0 0 1 0 1 1 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 251 0 0 16 0 16 16 0 8 0 bufpl 272 2674 0 105 172 0 172 172 0 8 0 anonpl 32 3877 0 0 32 0 32 32 0 247 0 amapchunkpl 152 18331 0 17913 31 1 30 30 0 158 13 amappl16 200 2189 0 2174 5 3 2 5 0 8 0 amappl15 192 24 0 24 2 2 0 1 0 8 0 amappl14 184 693 0 690 1 0 1 1 0 8 0 amappl13 176 166 0 153 1 0 1 1 0 8 0 amappl12 168 1236 0 1207 2 0 2 2 0 8 0 amappl11 160 4 0 4 1 1 0 1 0 8 0 amappl10 152 65 0 51 1 0 1 1 0 8 0 amappl9 144 300 0 298 1 0 1 1 0 8 0 amappl8 136 188 0 186 1 0 1 1 0 8 0 amappl7 128 210 0 194 1 0 1 1 0 8 0 amappl6 120 368 0 365 1 0 1 1 0 8 0 amappl5 112 100 0 90 1 0 1 1 0 8 0 amappl4 104 372 0 350 1 0 1 1 0 8 0 amappl3 96 3324 0 3237 3 0 3 3 0 8 0 amappl2 88 934 0 860 2 0 2 2 0 8 0 amappl1 80 13918 0 13290 14 0 14 14 0 8 0 amappl 88 5432 0 5288 5 0 5 5 0 92 0 uvmvnodes 80 106 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 10 0 2 1 0 1 1 0 8 0 uaddrrnd 24 893 0 861 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 893 0 861 1 0 1 1 0 8 0 vmmpekpl 168 9062 0 9007 3 0 3 3 0 8 0 vmmpepl 168 66325 0 64442 89 0 89 89 0 357 6 vmsppl 488 892 0 861 5 0 5 5 0 8 0 rwobjpl 80 21515 0 20455 23 0 23 23 0 8 0 pdppl 4096 1793 0 1722 111 36 75 85 0 8 4 pvpl 32 10761 0 0 87 0 87 87 0 265 0 pmappl 256 892 0 861 3 0 3 3 0 8 0 extentpl 40 46 0 28 1 0 1 1 0 8 0 phpool 112 474 0 41 13 0 13 13 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff834d2f2d) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff8350dd6d,ffffffff834750c4,643,ffffffff83457140) at __assert+0x29 sys/kern/subr_prf.c:-1 process_stop(ffff800045fe7568,8000000,1) at process_stop+0x3fe cursig(ffff80002a22b240,ffff80002a30e338,0) at cursig+0x509 x86_atomic_setbits_u32 sys/arch/amd64/compile/SYZKALLER/obj/machine/atomic.h:-1 [inline] cursig(ffff80002a22b240,ffff80002a30e338,0) at cursig+0x509 sys/kern/kern_sig.c:1446 userret(ffff80002a22b240) at userret+0x203 sys/kern/kern_sig.c:2208 syscall(ffff80002a30e470) at syscall+0x9ce mi_syscall_return sys/sys/syscall_mi.h:203 [inline] syscall(ffff80002a30e470) at syscall+0x9ce sys/arch/amd64/amd64/trap.c:812 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xc273591d780, count: -8 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffff80002999dff0) 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 mtx_enter(ffff800045fe7670) at mtx_enter+0x377 sys/kern/kern_lock.c:454 userret(ffff80002a22a7e0) at userret+0x79 proc_suspend_check sys/kern/kern_sig.c:2282 [inline] userret(ffff80002a22a7e0) at userret+0x79 sys/kern/kern_sig.c:2195 Xsyscall() at Xsyscall+0x156 end of kernel end trace frame: 0x78f7d58b5a30, count: 9 ddb{1}> trace x86_ipi_db(ffff80002999dff0) 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 mtx_enter(ffff800045fe7670) at mtx_enter+0x377 sys/kern/kern_lock.c:454 userret(ffff80002a22a7e0) at userret+0x79 proc_suspend_check sys/kern/kern_sig.c:2282 [inline] userret(ffff80002a22a7e0) at userret+0x79 sys/kern/kern_sig.c:2195 Xsyscall() at Xsyscall+0x156 end of kernel end trace frame: 0x78f7d58b5a30, count: -6