syzbot


panic: proc_dtor: non-empty p_ktr

Status: upstream: reported on 2025/06/26 21:36
Reported-by: syzbot+951d6d462fdeeebc9931@syzkaller.appspotmail.com
First crash: 23d, last: 23d

Sample crash report:
panic: proc_dtor: non-empty p_ktr
cpuid = 0
time = 1750973743
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0xc6/frame 0xfffffe0056cbb350
kdb_backtrace() at kdb_backtrace+0xd0/frame 0xfffffe0056cbb4b0
vpanic() at vpanic+0x257/frame 0xfffffe0056cbb670
panic() at panic+0xb5/frame 0xfffffe0056cbb730
proc_dtor() at proc_dtor+0x532/frame 0xfffffe0056cbb780
item_dtor() at item_dtor+0xc3/frame 0xfffffe0056cbb7d0
uma_zfree_arg() at uma_zfree_arg+0x10a/frame 0xfffffe0056cbb870
proc_reap() at proc_reap+0xab4/frame 0xfffffe0056cbb8d0
proc_to_reap() at proc_to_reap+0x6e9/frame 0xfffffe0056cbb930
kern_wait6() at kern_wait6+0x34b/frame 0xfffffe0056cbba10
sys_wait4() at sys_wait4+0x1c4/frame 0xfffffe0056cbbd10
amd64_syscall() at amd64_syscall+0x4e2/frame 0xfffffe0056cbbf30
fast_syscall_common() at fast_syscall_common+0xf8/frame 0xfffffe0056cbbf30
--- syscall (7, FreeBSD ELF64, wait4), rip = 0x3a223a, rsp = 0x820c78498, rbp = 0x820c784d0 ---
KDB: enter: panic
[ thread pid 764 tid 100098 ]
Stopped at      kdb_enter+0x6e: movq    $0,0x25b9d27(%rip)
db> 
db> set $lines = 0
db> set $maxwidth = 0
db> show registers
cs                        0x20
ds                        0x3b
es                        0x3b
fs                        0x13
gs                        0x1b
ss                        0x28
rax                       0x12
rcx         0xfffffe0072600000
rdx                    0x7ffff
rbx         0xffffffff827baf60  .str.27
rsp         0xfffffe0056cbb490
rbp         0xfffffe0056cbb4b0
rsi                    0x80001
rdi         0xffffffff81618ad9  printf+0x149
r8                           0
r9                  0xffffffff
r10                          0
r11         0xfffffe00540c1550
r12         0xfffffe00540c1000
r13         0xfffffffffffffffe
r14         0xffffffff827baf60  .str.27
r15                          0
rip         0xffffffff8160266e  kdb_enter+0x6e
rflags                    0x46
kdb_enter+0x6e: movq    $0,0x25b9d27(%rip)
db> show proc
Process 764 (syz-executor) at 0xfffffe0054007ae0:
 state: NORMAL
 uid: 0  gids: 0, 0, 5
 parent: pid 763 at 0xfffffe00540095c0
 ABI: FreeBSD ELF64
 flag: 0x10004000  flag2: 0
 arguments: ./syz-executor exec
 reaper: 0xfffffe0007809040 reapsubtree: 1
 sigparent: 20
 vmspace: 0xfffffe0007810b68
   (map 0xfffffe0007810b68)
   (map.pmap 0xfffffe0007810c08)
   (pmap 0xfffffe0007810c78)
 threads: 1
100098                   Run     CPU 0                       syz-executor
db> ps
  pid  ppid  pgrp   uid  state   wmesg   wchan               cmd
  890   765   765     0  R       (threaded)                  syz-executor
100188                   RunQ                                syz-executor
100219                   S       uwait   0xfffffe006e51e500  syz-executor
  889   767   767     0  R       (threaded)                  syz-executor
100208                   RunQ                                syz-executor
100214                   S       pipdwt  0xfffffe006e4d6000  syz-executor
100215                   S       uwait   0xfffffe006e51e400  syz-executor
100216                   S       uwait   0xfffffe006e51e200  syz-executor
  888   766   766     0  R       (threaded)                  syz-executor
100144                   RunQ                                syz-executor
100217                   S       uwait   0xfffffe006e51e800  syz-executor
  886     1   764     0  S       uwait   0xfffffe0059648e00  syz-executor
  882     1   767     0  S       uwait   0xfffffe0059644480  syz-executor
  873     1   766     0  S       uwait   0xfffffe006e51ee80  syz-executor
  869     1   765     0  S       uwait   0xfffffe00584e9000  syz-executor
  863     1   765     0  S       uwait   0xfffffe0059648b00  syz-executor
  862     1   764     0  SV      uwait   0xfffffe0059646200  syz-executor
  856     1   856     0  Ss+     ttyin   0xfffffe0057dfa8b0  getty
  855     1   855     0  Ss+     ttyin   0xfffffe0053f6d0b0  getty
  854     1   854     0  Ss+     ttyin   0xfffffe00582914b0  getty
  853     1   853     0  Ss+     ttyin   0xfffffe0053f6d8b0  getty
  852     1   852     0  Ss+     ttyin   0xfffffe0058291cb0  getty
  851     1   851     0  Ss+     ttyin   0xfffffe00582924b0  getty
  850     1   850     0  Ss+     ttyin   0xfffffe0053f6e0b0  getty
  849     1   849     0  Ss+     ttyin   0xfffffe0053f6e8b0  getty
  848     1   848     0  Ss+     ttyin   0xfffffe0053f6f0b0  getty
  839     0     0     0  DL      (threaded)                  [so_splice]
100097                   D       -       0xfffffe000776e380  [thr_0]
100148                   D       -       0xfffffe000776e3c0  [thr_1]
  837     1   767     0  SV      uwait   0xfffffe0059648480  syz-executor
  822   813   822     0  Ss      select  0xfffffe00596e7740  dhclient
  813     1   424    65  S       select  0xfffffe00596e79c0  dhclient
  808     0     0     0  DL      aiordy  0xfffffe0054009060  [aiod4]
  807     0     0     0  DL      aiordy  0xfffffe000780a060  [aiod3]
  806     0     0     0  DL      aiordy  0xfffffe0007809b00  [aiod2]
  805     0     0     0  DL      aiordy  0xfffffe0054006ac0  [aiod1]
  767   763   767     0  R                                   syz-executor
  766   763   766     0  R                                   syz-executor
  765   763   765     0  R                                   syz-executor
  764   763   764     0  R       CPU 0                       syz-executor
  763   761   761     0  R                                   syz-executor
  761     1   761     0  Ss      sigsusp 0xfffffe00540d8670  csh
   17     0     0     0  DL      syncer  0xffffffff83cbafa0  [syncer]
   16     0     0     0  DL      vlruwt  0xfffffe0007828040  [vnlru]
   15     0     0     0  DL      (threaded)                  [bufdaemon]
100080                   D       psleep  0xffffffff83cb9560  [bufdaemon]
100081                   D       -       0xffffffff83001ec0  [bufspacedaemon-0]
100095                   D       sdflush 0xfffffe00595948e8  [/ worker]
    9     0     0     0  DL      psleep  0xffffffff83d04400  [vmdaemon]
    8     0     0     0  DL      (threaded)                  [pagedaemon]
100078                   D       psleep  0xffffffff83cea4c8  [dom0]
100084                   D       launds  0xffffffff83cea4d4  [laundry: dom0]
100085                   D       umarcl  0xffffffff81dd8620  [uma]
    7     0     0     0  DL      -       0xffffffff8391acd0  [rand_harvestq]
    6     0     0     0  DL      pftm    0xffffffff843b1980  [pf purge]
    5     0     0     0  DL      waiting 0xffffffff84743700  [sctp_iterator]
    4     0     0     0  DL      (threaded)                  [cam]
100046                   D       -       0xffffffff838e5340  [doneq0]
100047                   D       -       0xffffffff838e52c0  [async]
100076                   D       -       0xffffffff838e5140  [scanner]
    3     0     0     0  DL      (threaded)                  [crypto]
100043                   D       crypto_ 0xffffffff83ce5d80  [crypto]
100044                   D       crypto_ 0xfffffe0007a6fc30  [crypto returns 0]
100045                   D       crypto_ 0xfffffe0007a6fc80  [crypto returns 1]
   14     0     0     0  DL      seqstat 0xfffffe0053ff0088  [sequencer 00]
   13     0     0     0  DL      (threaded)                  [geom]
100037                   D       -       0xffffffff83b45f20  [g_event]
100038                   D       -       0xffffffff83b45f40  [g_up]
100039                   D       -       0xffffffff83b45f60  [g_down]
    2     0     0     0  RL      (threaded)                  [clock]
100031                   I                                   [clock (0)]
100032                   Run     CPU 1                       [clock (1)]
   12     0     0     0  WL      (threaded)                  [intr]
100013                   I                                   [swi6: task queue]
100014                   I                                   [swi6: Giant taskq]
100016                   I                                   [swi5: fast taskq]
100033                   I                                   [swi1: netisr 0]
100034                   I                                   [swi1: hpts]
100035                   I                                   [swi1: hpts]
100048                   I                                   [irq24: virtio_pci0]
100049                   I                                   [irq25: virtio_pci0]
100050                   I                                   [irq26: virtio_pci0]
100051                   I                                   [irq27: virtio_pci0]
100052                   I                                   [irq28: virtio_pci1]
100053                   I                                   [irq29: virtio_pci1]
100054                   I                                   [irq30: virtio_pci1]
100055                   I                                   [irq31: virtio_pci1]
100056                   I                                   [irq32: virtio_pci1]
100061                   I                                   [irq10: virtio_pci2]
100063                   I                                   [irq1: atkbd0]
100064                   I                                   [irq12: psm0]
100065                   I                                   [swi0: uart uart++]
100069                   I                                   [swi1: pf send]
   11     0     0     0  RL      (threaded)                  [idle]
100003                   CanRun                              [idle: cpu0]
100004                   CanRun                              [idle: cpu1]
    1     0     1     0  SLs     wait    0xfffffe0007809040  [init]
   10     0     0     0  DL      audit_w 0xffffffff83ce6820  [audit]
    0     0     0     0  DLs     (threaded)                  [kernel]
100000                   D       parked  0xffffffff84c36ff0  [swapper]
100005                   D       -       0xfffffe0053e9c800  [softirq_0]
100006                   D       -       0xfffffe0053e9c700  [softirq_1]
100007                   D       -       0xfffffe0053e9c600  [if_io_tqg_0]
100008                   D       -       0xfffffe0053e9c500  [if_io_tqg_1]
100009                   D       -       0xfffffe0053e9c400  [if_config_tqg_0]
100010                   D       -       0xfffffe0007769b00  [kqueue_ctx taskq]
100011                   D       -       0xfffffe0007769a00  [jail_remove taskq]
100012                   D       -       0xfffffe0007769900  [bus taskq]
100015                   D       -       0xfffffe0007769600  [thread taskq]
100017                   D       -       0xfffffe0007769400  [aiod_kick taskq]
100018                   D       -       0xfffffe0007769300  [deferred_unmount ta]
100019                   D       -       0xfffffe0007769200  [inm_free taskq]
100020                   D       -       0xfffffe0007769100  [in6m_free taskq]
100021                   D       -       0xfffffe0007769000  [linuxkpi_irq_wq]
100022                   D       -       0xfffffe0007768e00  [linuxkpi_short_wq_0]
100023                   D       -       0xfffffe0007768e00  [linuxkpi_short_wq_1]
100024                   D       -       0xfffffe0007768e00  [linuxkpi_short_wq_2]
100025                   D       -       0xfffffe0007768e00  [linuxkpi_short_wq_3]
100026                   D       -       0xfffffe0007768d00  [linuxkpi_long_wq_0]
100027                   D       -       0xfffffe0007768d00  [linuxkpi_long_wq_1]
100028                   D       -       0xfffffe0007768d00  [linuxkpi_long_wq_2]
100029                   D       -       0xfffffe0007768d00  [linuxkpi_long_wq_3]
100036                   D       -       0xfffffe0007768a00  [firmware taskq]
100041                   D       -       0xfffffe0007768700  [crypto_0]
100042                   D       -       0xfffffe0007768700  [crypto_1]
100057                   D       -       0xfffffe0007768300  [vtnet0 rxq 0]
100058                   D       -       0xfffffe0007768200  [vtnet0 txq 0]
100059                   D       -       0xfffffe0007768100  [vtnet0 rxq 1]
100060                   D       -       0xfffffe0007768000  [vtnet0 txq 1]
100062                   D       vtbslp  0xfffffe0057d7eb80  [virtio_balloon]
100066                   D       -       0xffffffff827c0300  [deadlkres]
100070                   D       -       0xfffffe00593dc300  [acpi_task_0]
100071                   D       -       0xfffffe00593dc300  [acpi_task_1]
100072                   D       -       0xfffffe00593dc300  [acpi_task_2]
100074                   D       -       0xfffffe0007769c00  [mca taskq]
100075                   D       -       0xfffffe0007768600  [CAM taskq]
100077                   D       -       0xfffffe0007767b00  [ipsec_offload]
db> show all locks
Process 763 (syz-executor) thread 0xfffffe00540e8780 (100109)
exclusive sleep mutex pipe mutex (pipe mutex) r = 0 (0xfffffe0059824f70) locked @ /syzkaller/managers/main/kernel/sys/kern/sys_pipe.c:1506
db> 

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/26 21:35 freebsd-src 1ee33e3a578c ba7e550f console log report ci-freebsd-main panic: proc_dtor: non-empty p_ktr
* Struck through repros no longer work on HEAD.