login: witness: lock order reversal: 1st 0xfffffd806d9e73d0 inode (&ip->i_lock) @ /syzkaller/managers/multicore/kernel/sys/ufs/ufs/ufs_vnops.c:1547 2nd 0xfffffd806e6b9068 fdlock (&newfdp->fd_fd.fd_lock) @ /syzkaller/managers/multicore/kernel/sys/kern/vfs_syscalls.c:1113 lock order "&newfdp->fd_fd.fd_lock"(rwlock) -> "&ip->i_lock"(rrwlock) first seen at: #0 witness_checkorder+0x6cd sys/kern/subr_witness.c:902 #1 _rw_enter+0xc6 #2 _rrw_enter+0x60 sys/kern/kern_rwlock.c:410 #3 VOP_LOCK+0x4b sys/kern/vfs_vops.c:602 #4 vn_closefile+0x129 vn_lock sys/kern/vfs_vnops.c:549 [inline] #4 vn_closefile+0x129 vn_close sys/kern/vfs_vnops.c:288 [inline] #4 vn_closefile+0x129 sys/kern/vfs_vnops.c:575 #5 fdrop+0xe1 sys/kern/kern_descrip.c:1260 #6 closef+0x11d sys/kern/kern_descrip.c:1244 #7 finishdup+0x2e6 sys/kern/kern_descrip.c:679 #8 dodup3+0x622 sys/kern/kern_descrip.c:377 #9 syscall+0x576 mi_syscall sys/sys/syscall_mi.h:99 [inline] #9 syscall+0x576 sys/arch/amd64/amd64/trap.c:574 #10 Xsyscall+0x128 lock order "&ip->i_lock"(rrwlock) -> "&newfdp->fd_fd.fd_lock"(rwlock) first seen at: #0 witness_checkorder+0x6cd sys/kern/subr_witness.c:902 #1 _rw_enter_write+0x6f sys/kern/kern_rwlock.c:118 #2 doopenat+0x675 sys/kern/vfs_syscalls.c:1114 #3 syscall+0x576 mi_syscall sys/sys/syscall_mi.h:99 [inline] #3 syscall+0x576 sys/arch/amd64/amd64/trap.c:574 #4 Xsyscall+0x128 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(fffffd806e6b9068,9,ffffffff81f67672,459,0) at witness_checkorder+0x12ff witness_debugger sys/kern/subr_witness.c:2646 [inline] witness_checkorder(fffffd806e6b9068,9,ffffffff81f67672,459,0) at witness_checkorder+0x12ff sys/kern/subr_witness.c:1118 _rw_enter_write(fffffd806e6b9058,ffffffff81f67672,459) at _rw_enter_write+0x6f sys/kern/kern_rwlock.c:118 doopenat(ffff8000220752c8,ffffff9c,20000040,0,0,ffff80002213fd00) at doopenat+0x675 sys/kern/vfs_syscalls.c:1114 syscall(ffff80002213fd70) at syscall+0x576 mi_syscall sys/sys/syscall_mi.h:99 [inline] syscall(ffff80002213fd70) at syscall+0x576 sys/arch/amd64/amd64/trap.c:574 Xsyscall(6,0,c31aa08b0c8,0,c31aa08b0a8,c31aa08b0a0) at Xsyscall+0x128 end of kernel end trace frame: 0xc34a250e074, count: -6 ddb{1}> show registers rdi 0x3 rsi 0xffffffff821a0eb0 __sancov_gen_cov_switch_values.127 rbp 0xffff80002213f910 rbx 0x3 rdx 0x8b rcx 0x3 rax 0x3 r8 0xffffffff81024098 witness_checkorder+0x12d8 r9 0x5 r10 0x25e12dd868a6b974 r11 0xeb49ee5c9459572e r12 0xffffffff81f67672 cmd0646_9_tim_udma+0x34283 r13 0xfffffd800267c8e0 r14 0xffffffff82301d10 w_lodata+0x4eef0 r15 0xfffffd8002677660 rip 0xffffffff81cbe8b8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80002213f900 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor5297) pid=263249 stat=onproc flags process=0 proc=4000000 pri=32, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff800022074008,0xffff8000220744c8 process=0xffff8000220ec9f0 user=0xffff80002213a000, vmspace=0xfffffd807effd9d8 estcpu=4, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 19497 372037 33153 0 2 0 syz-executor5297 *19497 263249 33153 0 7 0x4000000 syz-executor5297 19497 322237 33153 0 2 0x4000000 syz-executor5297 33409 471237 11608 0 2 0 syz-executor5297 33409 382209 11608 0 2 0x4000000 syz-executor5297 33409 239839 11608 0 3 0x4000080 fsleep syz-executor5297 11608 229270 17583 0 3 0x80 nanosleep syz-executor5297 33153 132722 17583 0 3 0x80 nanosleep syz-executor5297 17583 496734 81294 0 3 0x82 nanosleep syz-executor5297 81294 203264 21618 0 3 0x10008a pause ksh 21618 520733 37348 0 3 0x92 select sshd 47281 495427 1 0 3 0x100083 ttyin getty 37348 41784 1 0 3 0x80 select sshd 29469 6099 20747 74 3 0x100092 bpf pflogd 20747 507031 1 0 3 0x80 netio pflogd 24537 215972 87342 73 7 0x100090 syslogd 87342 254846 1 0 3 0x100082 netio syslogd 73114 78067 1 77 3 0x100090 poll dhclient 98017 323566 1 0 3 0x80 poll dhclient 74559 147414 0 0 2 0x14200 zerothread 71203 92253 0 0 3 0x14200 aiodoned aiodoned 41633 196412 0 0 3 0x14200 syncer update 42316 296649 0 0 3 0x14200 cleaner cleaner 32922 367517 0 0 3 0x14200 reaper reaper 86620 2105 0 0 3 0x14200 pgdaemon pagedaemon 14478 134967 0 0 3 0x14200 bored crynlk 91986 33141 0 0 3 0x14200 bored crypto 68131 357478 0 0 3 0x40014200 acpi0 acpi0 38779 325652 0 0 3 0x40014200 idle1 23370 327463 0 0 3 0x14200 bored softnet 56629 496879 0 0 3 0x14200 bored systqmp 88958 129133 0 0 3 0x14200 bored systq 65721 185456 0 0 3 0x40014200 bored softclock 35209 401347 0 0 3 0x40014200 idle0 12391 351027 0 0 3 0x14200 bored smr 1 805 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 19497 (syz-executor5297) thread 0xffff8000220752c8 (263249) exclusive rrwlock inode r = 0 (0xfffffd806d9e73d0) locked @ /syzkaller/managers/multicore/kernel/sys/ufs/ufs/ufs_vnops.c:1547 #0 witness_lock+0x5a4 sys/kern/subr_witness.c:1201 #1 _rw_enter+0x43c sys/kern/kern_rwlock.c:280 #2 _rrw_enter+0x60 sys/kern/kern_rwlock.c:410 #3 VOP_LOCK+0x4b sys/kern/vfs_vops.c:602 #4 vn_lock+0x6e sys/kern/vfs_vnops.c:549 #5 spec_open+0x431 sys/kern/spec_vnops.c:159 #6 VOP_OPEN+0x6a sys/kern/vfs_vops.c:153 #7 vn_open+0x495 sys/kern/vfs_vnops.c:174 #8 doopenat+0x2a6 sys/kern/vfs_syscalls.c:1045 #9 syscall+0x576 mi_syscall sys/sys/syscall_mi.h:99 [inline] #9 syscall+0x576 sys/arch/amd64/amd64/trap.c:574 #10 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82376d70) locked @ /syzkaller/managers/multicore/kernel/sys/kern/sched_bsd.c:439 #0 witness_lock+0x5a4 sys/kern/subr_witness.c:1201 #1 ___mp_acquire_count+0x67 sys/kern/kern_lock.c:231 #2 mi_switch+0x3c2 sys/kern/sched_bsd.c:439 #3 sleep_finish+0x110 sys/kern/kern_synch.c:312 #4 _rw_enter+0x338 sys/kern/kern_rwlock.c:256 #5 _rrw_enter+0x60 sys/kern/kern_rwlock.c:410 #6 VOP_LOCK+0x4b sys/kern/vfs_vops.c:602 #7 vn_lock+0x6e sys/kern/vfs_vnops.c:549 #8 spec_open+0x431 sys/kern/spec_vnops.c:159 #9 VOP_OPEN+0x6a sys/kern/vfs_vops.c:153 #10 vn_open+0x495 sys/kern/vfs_vnops.c:174 #11 doopenat+0x2a6 sys/kern/vfs_syscalls.c:1045 #12 syscall+0x576 mi_syscall sys/sys/syscall_mi.h:99 [inline] #12 syscall+0x576 sys/arch/amd64/amd64/trap.c:574 #13 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9452 6382K 6383K 78643K 10539 0 0 pcb 25 9K 9K 78643K 57 0 0 rtable 61 2K 2K 78643K 125 0 0 ifaddr 25 7K 7K 78643K 26 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1467 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1167 73K 73K 78643K 1179 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 1K 78643K 2 0 0 VM map 2 1K 1K 78643K 2 0 0 sem 2 0K 0K 78643K 2 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12628 0 0 file desc 3 4K 5K 78643K 13 0 0 proc 52 50K 58K 78643K 279 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 in_multi 11 0K 0K 78643K 11 0 0 ether_multi 1 0K 0K 78643K 1 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 30 132K 132K 78643K 30 0 0 exec 0 0K 1K 78643K 179 0 0 pagedep 1 8K 8K 78643K 1 0 0 inodedep 1 32K 32K 78643K 1 0 0 newblk 1 0K 0K 78643K 1 0 0 VM swap 7 26K 26K 78643K 7 0 0 UVM amap 63 3K 3K 78643K 783 0 0 UVM aobj 2 2K 2K 78643K 2 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 NDP 4 0K 0K 78643K 4 0 0 temp 39 2692K 2756K 78643K 1994 0 0 SYN cache 2 16K 16K 78643K 2 0 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 inpcbpl 280 29 0 23 1 0 1 1 0 8 0 plimitpl 152 14 0 8 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtentry 112 23 0 1 1 0 1 1 0 8 0 syncache 264 5 0 5 1 0 1 1 0 8 1 tcpcb 544 8 0 5 1 0 1 1 0 8 0 pfosfp 40 846 0 423 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 8 0 0 1 0 1 1 0 8 0 pfstkey 112 8 0 0 1 0 1 1 0 8 0 pfstate 328 8 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 96 0 0 6 0 6 6 0 8 0 art_table 32 97 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 dino1pl 128 1399 0 26 45 0 45 45 0 8 0 ffsino 272 1399 0 26 92 0 92 92 0 8 0 nchpl 144 1570 0 38 57 0 57 57 0 8 0 uvmvnodes 72 1409 0 0 26 0 26 26 0 8 0 vnodes 200 1409 0 0 75 0 75 75 0 8 0 namei 1024 3576 0 3576 2 1 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 2337 0 2337 2 1 1 2 0 8 1 sigapl 432 211 0 195 2 0 2 2 0 8 0 futexpl 56 11 0 10 1 0 1 1 0 8 0 knotepl 112 5 0 0 1 0 1 1 0 8 0 kqueuepl 104 1 0 0 1 0 1 1 0 8 0 pipepl 112 134 0 127 2 1 1 1 0 8 0 fdescpl 488 212 0 195 3 0 3 3 0 8 0 filepl 152 976 0 923 3 0 3 3 0 8 0 lockfpl 104 6 0 6 1 1 0 1 0 8 0 lockfspl 32 3 0 3 1 1 0 1 0 8 0 sessionpl 112 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 55 1 0 1 1 0 8 0 zombiepl 144 195 0 195 2 1 1 1 0 8 1 processpl 840 227 0 195 4 0 4 4 0 8 0 procpl 600 235 0 199 3 0 3 3 0 8 0 sockpl 384 73 0 55 2 0 2 2 0 8 0 mcl4k 4096 4 0 0 1 0 1 1 0 8 0 mcl2k 2048 73 0 0 10 0 10 10 0 8 1 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 99 0 0 6 0 6 6 0 8 0 bufpl 256 2145 0 271 118 0 118 118 0 8 0 anonpl 16 19336 0 18024 8 2 6 7 0 125 0 amapchunkpl 152 576 0 527 2 0 2 2 0 158 0 amappl16 192 86 0 80 1 0 1 1 0 8 0 amappl14 176 16 0 15 2 1 1 1 0 8 0 amappl12 160 6 0 6 1 0 1 1 0 8 1 amappl11 152 41 0 23 1 0 1 1 0 8 0 amappl10 144 56 0 54 1 0 1 1 0 8 0 amappl9 136 415 0 414 1 0 1 1 0 8 0 amappl8 128 105 0 96 1 0 1 1 0 8 0 amappl7 120 20 0 19 1 0 1 1 0 8 0 amappl6 112 45 0 41 1 0 1 1 0 8 0 amappl5 104 138 0 125 1 0 1 1 0 8 0 amappl4 96 456 0 430 1 0 1 1 0 8 0 amappl3 88 107 0 101 1 0 1 1 0 8 0 amappl2 80 683 0 624 2 0 2 2 0 8 0 amappl1 72 13738 0 13276 15 5 10 15 0 8 0 amappl 72 441 0 412 1 0 1 1 0 75 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma64 64 259 0 259 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 17 0 17 1 1 0 1 0 8 0 aobjpl 64 1 0 0 1 0 1 1 0 8 0 uaddrrnd 24 212 0 195 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 212 0 195 1 0 1 1 0 8 0 vmmpekpl 168 5630 0 5608 2 0 2 2 0 8 0 vmmpepl 168 27579 0 26651 52 11 41 46 0 357 0 vmsppl 360 211 0 195 2 0 2 2 0 8 0 pdppl 4096 432 0 390 6 0 6 6 0 8 0 pvpl 32 81030 0 77868 30 2 28 28 0 265 2 pmappl 232 211 0 195 1 0 1 1 0 8 0 extentpl 40 39 0 25 1 0 1 1 0 8 0 phpool 112 250 0 4 8 0 8 8 0 8 0 ddb{1}>