login: panic: kernel diagnostic assertion "len >= 0 && !M_READONLY(m)" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/uipc_mbuf.c", line 1384 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *364687 69730 0 0 0 1K syz-executor.0 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff82574ae4) at panic+0x177 sys/kern/subr_prf.c:202 __assert(ffffffff825eb323,ffffffff825605fb,568,ffffffff8258ec0b) at __assert+0x25 sys/kern/subr_prf.c:161 m_align(fffffd807f00df00,ffffffe9) at m_align+0x1a0 sys/kern/uipc_mbuf.c:1385 bpf_movein(ffff8000211f6920,ffff800000ba4400,ffff8000211f6688,ffff8000211f6588) at bpf_movein+0x25e sys/net/bpf.c:228 bpfwrite(31700,ffff8000211f6920,1) at bpfwrite+0x169 sys/net/bpf.c:648 spec_write(ffff8000211f6780) at spec_write+0xd4 sys/kern/spec_vnops.c:309 VOP_WRITE(fffffd806a945e80,ffff8000211f6920,1,fffffd807f7d8900) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245 vn_write(fffffd806e526b58,ffff8000211f6920,1) at vn_write+0x1a1 sys/kern/vfs_vnops.c:414 dofilewritev(ffff8000ffff4000,3,ffff8000211f6920,1,ffff8000211f6a20) at dofilewritev+0x19c sys/kern/sys_generic.c:380 sys_pad_pwrite(ffff8000ffff4000,ffff8000211f69c8,ffff8000211f6a20) at sys_pad_pwrite+0x92 sys_pwrite sys/kern/vfs_syscalls.c:3354 [inline] sys_pad_pwrite(ffff8000ffff4000,ffff8000211f69c8,ffff8000211f6a20) at sys_pad_pwrite+0x92 sys/kern/vfs_syscalls.c:3426 syscall(ffff8000211f6a90) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000211f6a90) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd01b0, count: 2 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 *cpu1: kernel diagnostic assertion "len >= 0 && !M_READONLY(m)" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/uipc_mbuf.c", line 1384 ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff82574ae4) at panic+0x177 sys/kern/subr_prf.c:202 __assert(ffffffff825eb323,ffffffff825605fb,568,ffffffff8258ec0b) at __assert+0x25 sys/kern/subr_prf.c:161 m_align(fffffd807f00df00,ffffffe9) at m_align+0x1a0 sys/kern/uipc_mbuf.c:1385 bpf_movein(ffff8000211f6920,ffff800000ba4400,ffff8000211f6688,ffff8000211f6588) at bpf_movein+0x25e sys/net/bpf.c:228 bpfwrite(31700,ffff8000211f6920,1) at bpfwrite+0x169 sys/net/bpf.c:648 spec_write(ffff8000211f6780) at spec_write+0xd4 sys/kern/spec_vnops.c:309 VOP_WRITE(fffffd806a945e80,ffff8000211f6920,1,fffffd807f7d8900) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245 vn_write(fffffd806e526b58,ffff8000211f6920,1) at vn_write+0x1a1 sys/kern/vfs_vnops.c:414 dofilewritev(ffff8000ffff4000,3,ffff8000211f6920,1,ffff8000211f6a20) at dofilewritev+0x19c sys/kern/sys_generic.c:380 sys_pad_pwrite(ffff8000ffff4000,ffff8000211f69c8,ffff8000211f6a20) at sys_pad_pwrite+0x92 sys_pwrite sys/kern/vfs_syscalls.c:3354 [inline] sys_pad_pwrite(ffff8000ffff4000,ffff8000211f69c8,ffff8000211f6a20) at sys_pad_pwrite+0x92 sys/kern/vfs_syscalls.c:3426 syscall(ffff8000211f6a90) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000211f6a90) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd01b0, count: -13 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff8000211f63a0 rbx 0xffff800020ce9bff rdx 0x3fd rcx 0 rax 0x94 r8 0x101010101010101 r9 0x8080808080808080 r10 0xcd5ec4e5f8503773 r11 0x9c7a20474b84a592 r12 0xffff800020ce9a00 r13 0 r14 0 r15 0x1 rip 0xffffffff812d1e98 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000211f6390 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.0) pid=364687 stat=onproc flags process=0 proc=0 pri=50, usrpri=54, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffff5a40,0xffffffff82b00788 process=0xffff8000ffff8858 user=0xffff8000211f1000, vmspace=0xfffffd800871a8a0 estcpu=4, cpticks=2, pctcpu=0.0 user=0, sys=2, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND *69730 364687 37275 0 7 0 syz-executor.0 37275 191573 50221 0 3 0x82 nanoslp syz-executor.0 50221 494555 34292 0 3 0x82 thrsleep syz-execprog 50221 308370 34292 0 3 0x4000082 nanoslp syz-execprog 50221 196789 34292 0 3 0x4000082 thrsleep syz-execprog 50221 358270 34292 0 3 0x4000082 thrsleep syz-execprog 50221 43060 34292 0 3 0x4000082 nanoslp syz-execprog 50221 53110 34292 0 3 0x4000082 thrsleep syz-execprog 50221 390112 34292 0 3 0x4000082 kqread syz-execprog 50221 256333 34292 0 3 0x4000082 thrsleep syz-execprog 34292 335986 78258 0 3 0x10008a sigsusp ksh 78258 421043 18211 0 3 0x9a poll sshd 66153 326480 1 0 3 0x100083 ttyin getty 18211 493911 1 0 3 0x88 poll sshd 39269 253589 73322 74 3 0x100092 bpf pflogd 73322 130806 1 0 3 0x80 netio pflogd 51820 8090 38583 73 3 0x100090 kqread syslogd 38583 478581 1 0 3 0x100082 netio syslogd 80294 353740 1 0 3 0x100080 kqread resolvd 46656 146374 2415 77 3 0x100092 kqread dhcpleased 32737 95707 2415 77 3 0x100092 kqread dhcpleased 2415 286131 1 0 3 0x80 kqread dhcpleased 19441 208822 0 0 3 0x14200 bored smr 80298 174583 0 0 3 0x14200 pgzero zerothread 62727 111193 0 0 3 0x14200 aiodoned aiodoned 33897 499634 0 0 3 0x14200 syncer update 10050 331934 0 0 3 0x14200 cleaner cleaner 65868 18294 0 0 3 0x14200 reaper reaper 29076 29792 0 0 3 0x14200 pgdaemon pagedaemon 83437 431658 0 0 3 0x14200 bored viomb 59819 430275 0 0 3 0x40014200 acpi0 acpi0 73449 129572 0 0 3 0x40014200 idle1 9428 509197 0 0 3 0x14200 bored softnet 28542 325616 0 0 3 0x14200 bored systqmp 29170 459342 0 0 3 0x14200 bored systq 4448 345093 0 0 3 0x40014200 bored softclock 93833 393741 0 0 7 0x40014200 idle0 1 102493 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 69730 (syz-executor.0) thread 0xffff8000ffff4000 (364687) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82ac6568) #0 witness_lock+0x44d #1 vn_write+0x42 sys/kern/vfs_vnops.c:399 #2 dofilewritev+0x19c sys/kern/sys_generic.c:380 #3 sys_pad_pwrite+0x92 sys_pwrite sys/kern/vfs_syscalls.c:3354 [inline] #3 sys_pad_pwrite+0x92 sys/kern/vfs_syscalls.c:3426 #4 syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] #4 syscall+0x489 sys/arch/amd64/amd64/trap.c:585 #5 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10157 6522K 6522K 78643K 11247 0 pcb 13 8K 8K 78643K 13 0 rtable 84 2K 3K 78643K 146 0 ifaddr 37 9K 9K 78643K 40 0 counters 42 33K 33K 78643K 42 0 ioctlops 0 0K 4K 78643K 1480 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1168 73K 73K 78643K 1181 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 12548 0 file desc 4 9K 13K 78643K 20 0 proc 67 87K 99K 78643K 310 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 in_multi 22 1K 1K 78643K 22 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 25 122K 122K 78643K 25 0 exec 0 0K 2K 78643K 491 0 tdb 3 0K 0K 78643K 3 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 133 15K 16K 78643K 2511 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 7 0K 0K 78643K 7 0 temp 29 4682K 4745K 78643K 3615 0 kqueue 10 14K 14K 78643K 10 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 plcache 128 22 0 0 1 0 1 1 0 8 0 rtpcb 120 21 0 18 1 0 1 1 0 8 0 rtentry 112 34 0 1 1 0 1 1 0 8 0 unpcb 136 35 0 20 1 0 1 1 0 8 0 syncache 296 5 0 5 1 0 1 1 0 8 1 tcpcb 736 8 0 5 1 0 1 1 0 8 0 arp 120 4 0 0 1 0 1 1 0 8 0 inpcb 304 36 0 30 1 0 1 1 0 8 0 nd6 48 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 pfstitem 24 11 0 0 1 0 1 1 0 8 0 pfstkey 112 11 0 0 1 0 1 1 0 8 0 pfstate 320 11 0 0 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 256 145 0 0 10 0 10 10 0 8 0 art_table 32 146 0 0 2 0 2 2 0 8 0 art_node 16 33 0 3 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1451 0 49 88 0 88 88 0 8 0 ffsino 272 1451 0 49 94 0 94 94 0 8 0 nchpl 144 1679 0 59 60 0 60 60 0 8 0 uvmvnodes 80 1462 0 0 30 0 30 30 0 8 0 vnodes 224 1462 0 0 86 0 86 86 0 8 0 namei 1024 5181 0 5181 2 0 2 2 0 8 2 percpumem 16 33 0 0 1 0 1 1 0 8 0 scxspl 216 5194 0 5194 2 1 1 2 0 8 1 plimitpl 152 17 0 9 1 0 1 1 0 8 0 sigapl 424 353 0 322 5 0 5 5 0 8 1 knotepl 112 50 0 0 2 0 2 2 0 8 0 kqueuepl 216 6 0 0 1 0 1 1 0 8 0 pipepl 336 108 0 101 1 0 1 1 0 8 0 fdescpl 496 339 0 322 4 0 4 4 0 8 1 filepl 152 1364 0 1293 4 0 4 4 0 8 1 lockfpl 104 6 0 4 1 0 1 1 0 8 0 lockfspl 48 4 0 2 1 0 1 1 0 8 0 sessionpl 144 19 0 9 1 0 1 1 0 8 0 pgrppl 48 19 0 9 1 0 1 1 0 8 0 ucredpl 96 69 0 57 1 0 1 1 0 8 0 zombiepl 144 322 0 322 1 0 1 1 0 8 1 processpl 1064 353 0 322 3 0 3 3 0 8 0 procpl 672 360 0 322 4 0 4 4 0 8 0 sockpl 480 92 0 68 4 0 4 4 0 8 0 mcl8k 8192 4 0 0 1 0 1 1 0 8 0 mcl4k 4096 3 0 0 1 0 1 1 0 8 0 mcl2k 2048 57 0 0 8 0 8 8 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 113 0 0 7 0 7 7 0 8 0 bufpl 288 3562 0 143 245 0 245 245 0 8 0 anonpl 24 49886 0 46121 47 3 44 45 0 186 17 amapchunkpl 152 5051 0 4747 20 1 19 19 0 158 6 amappl16 200 157 0 95 5 1 4 4 0 8 0 amappl15 192 84 0 80 1 0 1 1 0 8 0 amappl14 184 2 0 1 1 0 1 1 0 8 0 amappl13 176 49 0 47 1 0 1 1 0 8 0 amappl12 168 16 0 16 1 0 1 1 0 8 1 amappl11 160 53 0 39 1 0 1 1 0 8 0 amappl10 152 29 0 25 1 0 1 1 0 8 0 amappl9 144 433 0 431 1 0 1 1 0 8 0 amappl8 136 437 0 417 1 0 1 1 0 8 0 amappl7 128 88 0 79 1 0 1 1 0 8 0 amappl6 120 180 0 162 2 0 2 2 0 8 1 amappl5 112 183 0 169 1 0 1 1 0 8 0 amappl4 104 710 0 687 2 0 2 2 0 8 1 amappl3 96 146 0 136 1 0 1 1 0 8 0 amappl2 88 483 0 440 3 0 3 3 0 8 1 amappl1 80 9893 0 9460 19 0 19 19 0 8 8 amappl 88 2171 0 2070 4 0 4 4 0 92 1 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 2 0 0 1 0 1 1 0 8 0 uaddrrnd 24 339 0 322 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 339 0 322 1 0 1 1 0 8 0 vmmpekpl 168 8114 0 8096 2 0 2 2 0 8 0 vmmpepl 168 32436 0 31303 91 0 91 91 0 357 40 vmsppl 368 338 0 322 3 0 3 3 0 8 1 rwobjpl 56 11010 0 8820 41 0 41 41 0 8 5 pdppl 4096 685 0 644 79 26 53 57 0 8 12 pvpl 32 217922 0 211220 247 1 246 246 0 265 183 pmappl 248 338 0 322 2 0 2 2 0 8 0 extentpl 40 58 0 38 1 0 1 1 0 8 0 phpool 112 549 0 29 15 0 15 15 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp x86_ipi_db(ffffffff82952ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:393 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(ffffffff82ac6360) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82ac6360) at __mp_lock+0x122 sys/kern/kern_lock.c:147 softintr_dispatch(0) at softintr_dispatch+0x4e sys/arch/amd64/amd64/softintr.c:88 Xsoftclock() at Xsoftclock+0x1f acpicpu_idle() at acpicpu_idle+0x312 sys/dev/acpi/acpicpu.c:1206 sched_idle(ffffffff82952ff0) at sched_idle+0x417 sys/kern/kern_sched.c:178 end trace frame: 0x0, count: 7 ddb{0}> trace x86_ipi_db(ffffffff82952ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:393 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(ffffffff82ac6360) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82ac6360) at __mp_lock+0x122 sys/kern/kern_lock.c:147 softintr_dispatch(0) at softintr_dispatch+0x4e sys/arch/amd64/amd64/softintr.c:88 Xsoftclock() at Xsoftclock+0x1f acpicpu_idle() at acpicpu_idle+0x312 sys/dev/acpi/acpicpu.c:1206 sched_idle(ffffffff82952ff0) at sched_idle+0x417 sys/kern/kern_sched.c:178 end trace frame: 0x0, count: -8 ddb{0}> machine ddbcpu 1 Stopped at db_enter+0x18: addq $0x8,%rsp db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff82574ae4) at panic+0x177 sys/kern/subr_prf.c:202 __assert(ffffffff825eb323,ffffffff825605fb,568,ffffffff8258ec0b) at __assert+0x25 sys/kern/subr_prf.c:161 m_align(fffffd807f00df00,ffffffe9) at m_align+0x1a0 sys/kern/uipc_mbuf.c:1385 bpf_movein(ffff8000211f6920,ffff800000ba4400,ffff8000211f6688,ffff8000211f6588) at bpf_movein+0x25e sys/net/bpf.c:228 bpfwrite(31700,ffff8000211f6920,1) at bpfwrite+0x169 sys/net/bpf.c:648 spec_write(ffff8000211f6780) at spec_write+0xd4 sys/kern/spec_vnops.c:309 VOP_WRITE(fffffd806a945e80,ffff8000211f6920,1,fffffd807f7d8900) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245 vn_write(fffffd806e526b58,ffff8000211f6920,1) at vn_write+0x1a1 sys/kern/vfs_vnops.c:414 dofilewritev(ffff8000ffff4000,3,ffff8000211f6920,1,ffff8000211f6a20) at dofilewritev+0x19c sys/kern/sys_generic.c:380 sys_pad_pwrite(ffff8000ffff4000,ffff8000211f69c8,ffff8000211f6a20) at sys_pad_pwrite+0x92 sys_pwrite sys/kern/vfs_syscalls.c:3354 [inline] sys_pad_pwrite(ffff8000ffff4000,ffff8000211f69c8,ffff8000211f6a20) at sys_pad_pwrite+0x92 sys/kern/vfs_syscalls.c:3426 syscall(ffff8000211f6a90) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000211f6a90) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd01b0, count: 2 ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff82574ae4) at panic+0x177 sys/kern/subr_prf.c:202 __assert(ffffffff825eb323,ffffffff825605fb,568,ffffffff8258ec0b) at __assert+0x25 sys/kern/subr_prf.c:161 m_align(fffffd807f00df00,ffffffe9) at m_align+0x1a0 sys/kern/uipc_mbuf.c:1385 bpf_movein(ffff8000211f6920,ffff800000ba4400,ffff8000211f6688,ffff8000211f6588) at bpf_movein+0x25e sys/net/bpf.c:228 bpfwrite(31700,ffff8000211f6920,1) at bpfwrite+0x169 sys/net/bpf.c:648 spec_write(ffff8000211f6780) at spec_write+0xd4 sys/kern/spec_vnops.c:309 VOP_WRITE(fffffd806a945e80,ffff8000211f6920,1,fffffd807f7d8900) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245 vn_write(fffffd806e526b58,ffff8000211f6920,1) at vn_write+0x1a1 sys/kern/vfs_vnops.c:414 dofilewritev(ffff8000ffff4000,3,ffff8000211f6920,1,ffff8000211f6a20) at dofilewritev+0x19c sys/kern/sys_generic.c:380 sys_pad_pwrite(ffff8000ffff4000,ffff8000211f69c8,ffff8000211f6a20) at sys_pad_pwrite+0x92 sys_pwrite sys/kern/vfs_syscalls.c:3354 [inline] sys_pad_pwrite(ffff8000ffff4000,ffff8000211f69c8,ffff8000211f6a20) at sys_pad_pwrite+0x92 sys/kern/vfs_syscalls.c:3426 syscall(ffff8000211f6a90) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000211f6a90) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd01b0, count: -13 ddb{1}>