login: panic: kernel diagnostic assertion "len >= 0 && !M_READONLY(m)" failed: file "/syzkaller/managers/main/kernel/sys/kern/uipc_mbuf.c", line 1384 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *481647 94335 0 0 0 0 syz-executor.0 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff8254be5b) at panic+0x161 sys/kern/subr_prf.c:202 __assert(ffffffff825bbf89,ffffffff825cdd9d,568,ffffffff8255ec6a) at __assert+0x25 sys/kern/subr_prf.c:161 m_align(fffffd806c3b3000,ffffffeb) at m_align+0x1a0 sys/kern/uipc_mbuf.c:1385 bpf_movein(ffff800021677d70,ffff800000b8ba00,ffff800021677ad8,ffff8000216779d8) at bpf_movein+0x25e sys/net/bpf.c:228 bpfwrite(21700,ffff800021677d70,1) at bpfwrite+0x128 sys/net/bpf.c:648 spec_write(ffff800021677bd0) at spec_write+0xcb sys/kern/spec_vnops.c:309 VOP_WRITE(fffffd806c2e3780,ffff800021677d70,1,fffffd807f7d8900) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245 vn_write(fffffd806c67fa60,ffff800021677d70,1) at vn_write+0x19c sys/kern/vfs_vnops.c:414 dofilewritev(ffff8000215ee2a0,3,ffff800021677d70,1,ffff800021677e70) at dofilewritev+0x19c sys/kern/sys_generic.c:380 sys_pad_pwrite(ffff8000215ee2a0,ffff800021677e18,ffff800021677e70) at sys_pad_pwrite+0x92 sys_pwrite sys/kern/vfs_syscalls.c:3354 [inline] sys_pad_pwrite(ffff8000215ee2a0,ffff800021677e18,ffff800021677e70) at sys_pad_pwrite+0x92 sys/kern/vfs_syscalls.c:3426 syscall(ffff800021677ee0) at syscall+0x44e sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffee550, 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> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic *cpu0: kernel diagnostic assertion "len >= 0 && !M_READONLY(m)" failed: file "/syzkaller/managers/main/kernel/sys/kern/uipc_mbuf.c", line 1384 ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff8254be5b) at panic+0x161 sys/kern/subr_prf.c:202 __assert(ffffffff825bbf89,ffffffff825cdd9d,568,ffffffff8255ec6a) at __assert+0x25 sys/kern/subr_prf.c:161 m_align(fffffd806c3b3000,ffffffeb) at m_align+0x1a0 sys/kern/uipc_mbuf.c:1385 bpf_movein(ffff800021677d70,ffff800000b8ba00,ffff800021677ad8,ffff8000216779d8) at bpf_movein+0x25e sys/net/bpf.c:228 bpfwrite(21700,ffff800021677d70,1) at bpfwrite+0x128 sys/net/bpf.c:648 spec_write(ffff800021677bd0) at spec_write+0xcb sys/kern/spec_vnops.c:309 VOP_WRITE(fffffd806c2e3780,ffff800021677d70,1,fffffd807f7d8900) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245 vn_write(fffffd806c67fa60,ffff800021677d70,1) at vn_write+0x19c sys/kern/vfs_vnops.c:414 dofilewritev(ffff8000215ee2a0,3,ffff800021677d70,1,ffff800021677e70) at dofilewritev+0x19c sys/kern/sys_generic.c:380 sys_pad_pwrite(ffff8000215ee2a0,ffff800021677e18,ffff800021677e70) at sys_pad_pwrite+0x92 sys_pwrite sys/kern/vfs_syscalls.c:3354 [inline] sys_pad_pwrite(ffff8000215ee2a0,ffff800021677e18,ffff800021677e70) at sys_pad_pwrite+0x92 sys/kern/vfs_syscalls.c:3426 syscall(ffff800021677ee0) at syscall+0x44e sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffee550, count: -13 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800021677800 rbx 0x30 rdx 0x3fd rcx 0 rax 0x8f r8 0x101010101010101 r9 0x8080808080808080 r10 0x476fc975529229ed r11 0x1eb683e0a1a0e7f1 r12 0 r13 0xffffffeb r14 0 r15 0x1 rip 0xffffffff8172f728 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000216777f0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (syz-executor.0) pid=481647 stat=onproc flags process=0 proc=0 pri=50, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000215eed20,0xffffffff829b39d0 process=0xffff800021601788 user=0xffff800021672000, vmspace=0xfffffd807f018880 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND *94335 481647 96823 0 7 0 syz-executor.0 96823 324807 28509 0 3 0x82 nanoslp syz-executor.0 28509 483593 62814 0 3 0x82 thrsleep syz-execprog 28509 502126 62814 0 3 0x4000082 nanoslp syz-execprog 28509 180171 62814 0 3 0x4000082 kqread syz-execprog 28509 356737 62814 0 3 0x4000082 thrsleep syz-execprog 28509 506205 62814 0 3 0x4000082 thrsleep syz-execprog 28509 120421 62814 0 3 0x4000082 thrsleep syz-execprog 28509 173789 62814 0 3 0x4000082 thrsleep syz-execprog 28509 70070 62814 0 3 0x4000082 thrsleep syz-execprog 28509 224253 62814 0 3 0x4000082 thrsleep syz-execprog 62814 342121 26475 0 3 0x10008a sigsusp ksh 26475 51520 73765 0 3 0x9a poll sshd 51573 437142 1 0 3 0x100083 ttyin getty 73765 35307 1 0 3 0x88 poll sshd 23459 164256 34238 73 3 0x100090 kqread syslogd 34238 388293 1 0 3 0x100082 netio syslogd 45030 301755 1 0 3 0x100080 kqread resolvd 3161 325635 53295 77 3 0x100092 kqread dhcpleased 25977 255276 53295 77 3 0x100092 kqread dhcpleased 53295 275026 1 0 3 0x80 kqread dhcpleased 17664 267155 0 0 3 0x14200 bored smr 16294 421722 0 0 2 0x14200 zerothread 38496 204646 0 0 3 0x14200 aiodoned aiodoned 54000 67250 0 0 3 0x14200 syncer update 29099 455103 0 0 3 0x14200 cleaner cleaner 65205 185809 0 0 3 0x14200 reaper reaper 92278 446371 0 0 3 0x14200 pgdaemon pagedaemon 4269 89179 0 0 3 0x14200 bored viomb 4607 111194 0 0 3 0x40014200 acpi0 acpi0 16002 428283 0 0 3 0x14200 bored softnet 96852 337879 0 0 3 0x14200 bored systqmp 25950 249961 0 0 3 0x14200 bored systq 22348 35241 0 0 3 0x40014200 bored softclock 3920 108294 0 0 3 0x40014200 idle0 1 438961 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10139 6448K 6448K 78643K 11229 0 pcb 13 8K 8K 78643K 13 0 rtable 84 2K 3K 78643K 146 0 ifaddr 32 8K 8K 78643K 32 0 counters 20 16K 16K 78643K 20 0 ioctlops 0 0K 2K 78643K 26 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1167 73K 73K 78643K 1180 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 0K 0K 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 3 8K 12K 78643K 18 0 proc 55 54K 63K 78643K 254 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 460 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 123 13K 13K 78643K 2235 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 6 0K 0K 78643K 6 0 temp 24 4674K 4737K 78643K 3483 0 kqueue 10 14K 14K 78643K 10 0 SYN cache 2 16K 16K 78643K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 23 0 20 1 0 1 1 0 8 0 rtentry 112 34 0 1 1 0 1 1 0 8 0 unpcb 136 33 0 20 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 arp 88 4 0 0 1 0 1 1 0 8 0 inpcb 304 29 0 23 1 0 1 1 0 8 0 nd6 48 3 0 0 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 144 0 0 9 0 9 9 0 8 0 art_table 32 145 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 1442 0 48 88 0 88 88 0 8 0 ffsino 240 1442 0 48 83 0 83 83 0 8 1 nchpl 144 1670 0 57 60 0 60 60 0 8 0 uvmvnodes 80 1452 0 0 30 0 30 30 0 8 0 vnodes 224 1452 0 0 86 0 86 86 0 8 0 namei 1024 4920 0 4920 3 1 2 2 0 8 2 scxspl 216 5199 0 5199 10 3 7 8 0 8 7 plimitpl 152 16 0 9 1 0 1 1 0 8 0 sigapl 424 330 0 302 5 0 5 5 0 8 1 knotepl 112 192 0 162 2 0 2 2 0 8 0 kqueuepl 184 6 0 0 1 0 1 1 0 8 0 pipepl 304 103 0 96 2 1 1 1 0 8 0 fdescpl 432 317 0 302 3 0 3 3 0 8 1 filepl 120 1239 0 1173 3 0 3 3 0 8 0 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 18 0 9 1 0 1 1 0 8 0 pgrppl 48 18 0 9 1 0 1 1 0 8 0 ucredpl 96 64 0 54 1 0 1 1 0 8 0 zombiepl 144 302 0 302 2 1 1 1 0 8 1 processpl 1000 330 0 302 5 0 5 5 0 8 1 procpl 672 338 0 302 4 0 4 4 0 8 0 sockpl 448 85 0 63 3 0 3 3 0 8 0 mcl8k 8192 9 0 9 2 1 1 1 0 8 1 mcl4k 4096 5 0 5 2 1 1 1 0 8 1 mcl2k 2048 5328 0 5298 6 2 4 6 0 8 0 mtagpl 96 4 0 4 1 1 0 1 0 8 0 mbufpl 256 9785 0 9685 7 0 7 7 0 8 0 bufpl 288 3491 0 145 239 0 239 239 0 8 0 anonpl 24 49582 0 46149 47 3 44 44 0 188 19 amapchunkpl 152 4793 0 4509 20 1 19 19 0 158 7 amappl16 200 111 0 54 4 1 3 3 0 8 0 amappl15 192 85 0 80 1 0 1 1 0 8 0 amappl14 184 2 0 0 1 0 1 1 0 8 0 amappl13 176 47 0 45 2 1 1 1 0 8 0 amappl12 168 14 0 14 1 1 0 1 0 8 0 amappl11 160 49 0 38 1 0 1 1 0 8 0 amappl10 152 24 0 22 2 1 1 1 0 8 0 amappl9 144 422 0 420 1 0 1 1 0 8 0 amappl8 136 414 0 394 1 0 1 1 0 8 0 amappl7 128 79 0 73 1 0 1 1 0 8 0 amappl6 120 179 0 159 2 0 2 2 0 8 0 amappl5 112 188 0 178 1 0 1 1 0 8 0 amappl4 104 656 0 632 2 0 2 2 0 8 1 amappl3 96 139 0 128 1 0 1 1 0 8 0 amappl2 88 474 0 431 3 0 3 3 0 8 1 amappl1 80 9333 0 8933 19 1 18 18 0 8 9 amappl 88 1915 0 1825 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 24 317 0 302 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 317 0 302 1 0 1 1 0 8 0 vmmpekpl 168 7732 0 7715 1 0 1 1 0 8 0 vmmpepl 168 30752 0 29694 89 1 88 88 0 357 41 vmsppl 272 316 0 302 3 1 2 2 0 8 1 rwobjpl 24 10539 0 8413 17 0 17 17 0 8 1 pdppl 4096 640 0 604 78 26 52 52 0 8 16 pvpl 32 211697 0 205414 262 3 259 259 0 265 202 pmappl 216 316 0 302 2 0 2 2 0 8 1 extentpl 40 58 0 38 1 0 1 1 0 8 0 phpool 112 531 0 34 15 0 15 15 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff8254be5b) at panic+0x161 sys/kern/subr_prf.c:202 __assert(ffffffff825bbf89,ffffffff825cdd9d,568,ffffffff8255ec6a) at __assert+0x25 sys/kern/subr_prf.c:161 m_align(fffffd806c3b3000,ffffffeb) at m_align+0x1a0 sys/kern/uipc_mbuf.c:1385 bpf_movein(ffff800021677d70,ffff800000b8ba00,ffff800021677ad8,ffff8000216779d8) at bpf_movein+0x25e sys/net/bpf.c:228 bpfwrite(21700,ffff800021677d70,1) at bpfwrite+0x128 sys/net/bpf.c:648 spec_write(ffff800021677bd0) at spec_write+0xcb sys/kern/spec_vnops.c:309 VOP_WRITE(fffffd806c2e3780,ffff800021677d70,1,fffffd807f7d8900) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245 vn_write(fffffd806c67fa60,ffff800021677d70,1) at vn_write+0x19c sys/kern/vfs_vnops.c:414 dofilewritev(ffff8000215ee2a0,3,ffff800021677d70,1,ffff800021677e70) at dofilewritev+0x19c sys/kern/sys_generic.c:380 sys_pad_pwrite(ffff8000215ee2a0,ffff800021677e18,ffff800021677e70) at sys_pad_pwrite+0x92 sys_pwrite sys/kern/vfs_syscalls.c:3354 [inline] sys_pad_pwrite(ffff8000215ee2a0,ffff800021677e18,ffff800021677e70) at sys_pad_pwrite+0x92 sys/kern/vfs_syscalls.c:3426 syscall(ffff800021677ee0) at syscall+0x44e sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffee550, count: -13 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 panic(ffffffff8254be5b) at panic+0x161 sys/kern/subr_prf.c:202 __assert(ffffffff825bbf89,ffffffff825cdd9d,568,ffffffff8255ec6a) at __assert+0x25 sys/kern/subr_prf.c:161 m_align(fffffd806c3b3000,ffffffeb) at m_align+0x1a0 sys/kern/uipc_mbuf.c:1385 bpf_movein(ffff800021677d70,ffff800000b8ba00,ffff800021677ad8,ffff8000216779d8) at bpf_movein+0x25e sys/net/bpf.c:228 bpfwrite(21700,ffff800021677d70,1) at bpfwrite+0x128 sys/net/bpf.c:648 spec_write(ffff800021677bd0) at spec_write+0xcb sys/kern/spec_vnops.c:309 VOP_WRITE(fffffd806c2e3780,ffff800021677d70,1,fffffd807f7d8900) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245 vn_write(fffffd806c67fa60,ffff800021677d70,1) at vn_write+0x19c sys/kern/vfs_vnops.c:414 dofilewritev(ffff8000215ee2a0,3,ffff800021677d70,1,ffff800021677e70) at dofilewritev+0x19c sys/kern/sys_generic.c:380 sys_pad_pwrite(ffff8000215ee2a0,ffff800021677e18,ffff800021677e70) at sys_pad_pwrite+0x92 sys_pwrite sys/kern/vfs_syscalls.c:3354 [inline] sys_pad_pwrite(ffff8000215ee2a0,ffff800021677e18,ffff800021677e70) at sys_pad_pwrite+0x92 sys/kern/vfs_syscalls.c:3426 syscall(ffff800021677ee0) at syscall+0x44e sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffee550, count: -13 ddb>