Add a syzkaller reproducer.

misc/syzkaller29.sh

@@ -0,0 +1,130 @@
+#!/bin/sh
+
+# panic: uma_zalloc_debug: called within spinlock or critical section
+# cpuid = 9
+# time = 1606151277
+# KDB: stack backtrace:
+# db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe0101c628a0
+# vpanic() at vpanic+0x181/frame 0xfffffe0101c628f0
+# panic() at panic+0x43/frame 0xfffffe0101c62950
+# uma_zalloc_arg() at uma_zalloc_arg+0x1e6/frame 0xfffffe0101c62990
+# cpuset_modify_domain() at cpuset_modify_domain+0x1bf/frame 0xfffffe0101c62a10
+# kern_cpuset_setdomain() at kern_cpuset_setdomain+0x402/frame 0xfffffe0101c62aa0
+# sys_cpuset_setdomain() at sys_cpuset_setdomain+0x26/frame 0xfffffe0101c62ac0
+# amd64_syscall() at amd64_syscall+0x147/frame 0xfffffe0101c62bf0
+# fast_syscall_common() at fast_syscall_common+0xf8/frame 0xfffffe0101c62bf0
+# --- syscall (0, FreeBSD ELF64, nosys), rip = 0x800380d4a, rsp = 0x7fffffffe4b8, rbp = 0x7fffffffe4f0 ---
+# KDB: enter: panic
+# [ thread pid 81187 tid 100369 ]
+# Stopped at      kdb_enter+0x37: movq    $0,0x10b3236(%rip)
+# db> x/s version
+# version: FreeBSD 13.0-CURRENT #0 r367945: Mon Nov 23 09:10:40 CET 2020
+# pho@t2.osted.lan:/usr/src/sys/amd64/compile/PHO
+# db>
+
+# $FreeBSD$
+
+[ `uname -p` != "amd64" ] && exit 0
+
+# Fixed by r368116
+
+. ../default.cfg
+cat > /tmp/syzkaller29.c <<EOF
+// https://syzkaller.appspot.com/bug?id=c3452066dba9238c4551010eb130944442d9174f
+// autogenerated by syzkaller (https://github.com/google/syzkaller)
+// Reported-by: syzbot+6743fa07b9b7528dc561@syzkaller.appspotmail.com
+
+#define _GNU_SOURCE
+
+#include <sys/types.h>
+
+#include <pwd.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/endian.h>
+#include <sys/syscall.h>
+#include <sys/wait.h>
+#include <time.h>
+#include <unistd.h>
+
+static void kill_and_wait(int pid, int* status)
+{
+  kill(pid, SIGKILL);
+  while (waitpid(-1, status, 0) != pid) {
+  }
+}
+
+static void sleep_ms(uint64_t ms)
+{
+  usleep(ms * 1000);
+}
+
+static uint64_t current_time_ms(void)
+{
+  struct timespec ts;
+  if (clock_gettime(CLOCK_MONOTONIC, &ts))
+    exit(1);
+  return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
+}
+
+static void execute_one(void);
+
+#define WAIT_FLAGS 0
+
+static void loop(void)
+{
+  int iter = 0;
+  for (;; iter++) {
+    int pid = fork();
+    if (pid < 0)
+      exit(1);
+    if (pid == 0) {
+      execute_one();
+      exit(0);
+    }
+    int status = 0;
+    uint64_t start = current_time_ms();
+    for (;;) {
+      if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
+        break;
+      sleep_ms(1);
+      if (current_time_ms() - start < 5 * 1000)
+        continue;
+      kill_and_wait(pid, &status);
+      break;
+    }
+  }
+}
+
+void execute_one(void)
+{
+  *(uint64_t*)0x20000240 = 1;
+  *(uint64_t*)0x20000248 = 0;
+  *(uint64_t*)0x20000250 = 0;
+  *(uint64_t*)0x20000258 = 0;
+  syscall(SYS_cpuset_setdomain, 2ul, 2ul, 0ul, 0x20ul, 0x20000240ul, 4ul);
+  *(uint64_t*)0x20000240 = 1;
+  *(uint64_t*)0x20000248 = 0;
+  *(uint64_t*)0x20000250 = 0;
+  *(uint64_t*)0x20000258 = 0;
+  syscall(SYS_cpuset_setdomain, 3ul, 2ul, 0ul, 0x20ul, 0x20000240ul, 1ul);
+}
+int main(void)
+{
+  syscall(SYS_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x1012ul, -1, 0ul);
+  loop();
+  return 0;
+}
+EOF
+mycc -o /tmp/syzkaller29 -Wall -Wextra -O0 /tmp/syzkaller29.c ||
+    exit 1
+
+(cd /tmp; timeout 3m ./syzkaller29)
+
+rm -rf /tmp/syzkaller29 syzkaller29.c /tmp/syzkaller.*
+exit 0