Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 7 Jun 2020 12:15:42 +0000 (UTC)
From:      Peter Holm <pho@FreeBSD.org>
To:        src-committers@freebsd.org, svn-src-user@freebsd.org
Subject:   svn commit: r361890 - user/pho/stress2/misc
Message-ID:  <202006071215.057CFgsI046296@repo.freebsd.org>

next in thread | raw e-mail | index | archive | help
Author: pho
Date: Sun Jun  7 12:15:41 2020
New Revision: 361890
URL: https://svnweb.freebsd.org/changeset/base/361890

Log:
  Added a syzkaller reproducer.

Added:
  user/pho/stress2/misc/syzkaller13.sh   (contents, props changed)

Added: user/pho/stress2/misc/syzkaller13.sh
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ user/pho/stress2/misc/syzkaller13.sh	Sun Jun  7 12:15:41 2020	(r361890)
@@ -0,0 +1,249 @@
+#!/bin/sh
+
+# Kernel page fault with the following non-sleepable locks held:
+# exclusive sleep mutex so_rcv (so_rcv) r = 0 (0xfffffe012b5ee300) locked @ kern/uipc_usrreq.c:1272
+# exclusive sleep mutex socket (socket) r = 0 (0xfffffe012b5ee1a8) locked @ kern/uipc_usrreq.c:1265
+# shared rw unp_link_rwlock (unp_link_rwlock) r = 0 (0xffffffff81d99640) locked @ kern/uipc_usrreq.c:1334
+# stack backtrace:
+# #0 0xffffffff80c35701 at witness_debugger+0x71
+# #1 0xffffffff80c3669d at witness_warn+0x40d
+# #2 0xffffffff8106fb90 at trap_pfault+0x80
+# #3 0xffffffff8106f1a5 at trap+0x2a5
+# #4 0xffffffff810450d8 at calltrap+0x8
+# #5 0xffffffff80bc6fcc at sendfile_iodone+0x1ac
+# #6 0xffffffff80f3d98a at vnode_pager_generic_getpages_done_async+0x3a
+# #7 0xffffffff80c8236c at bufdone+0x6c
+# #8 0xffffffff80b0c06e at g_io_deliver+0x25e
+# #9 0xffffffff80b0c06e at g_io_deliver+0x25e
+# #10 0xffffffff80b08dfd at g_disk_done+0xed
+# #11 0xffffffff803ac1f3 at dadone+0x603
+# #12 0xffffffff8037ddf2 at xpt_done_process+0x382
+# #13 0xffffffff8037fdb5 at xpt_done_td+0xf5
+# #14 0xffffffff80b85b10 at fork_exit+0x80
+# #15 0xffffffff8104611e at fork_trampoline+0xe
+# 
+# 
+# Fatal trap 12: page fault while in kernel mode
+# cpuid = 23; apic id = 2b
+# fault virtual address   = 0x8
+# fault code              = supervisor read data, page not present
+# instruction pointer     = 0x20:0xffffffff80c74bc0
+# stack pointer           = 0x0:0xfffffe0126b118e0
+# frame pointer           = 0x0:0xfffffe0126b11920
+# code segment            = base 0x0, limit 0xfffff, type 0x1b
+#                         = DPL 0, pres 1, long 1, def32 0, gran 1
+# processor eflags        = interrupt enabled, resume, IOPL = 0
+# current process         = 32 (doneq0)
+# trap number             = 12
+# panic: page fault
+# cpuid = 23
+# time = 1591531029
+# KDB: stack backtrace:
+# db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe0126b11590
+# vpanic() at vpanic+0x182/frame 0xfffffe0126b115e0
+# panic() at panic+0x43/frame 0xfffffe0126b11640
+# trap_fatal() at trap_fatal+0x387/frame 0xfffffe0126b116a0
+# trap_pfault() at trap_pfault+0x99/frame 0xfffffe0126b11700
+# trap() at trap+0x2a5/frame 0xfffffe0126b11810
+# calltrap() at calltrap+0x8/frame 0xfffffe0126b11810
+# --- trap 0xc, rip = 0xffffffff80c74bc0, rsp = 0xfffffe0126b118e0, rbp = 0xfffffe0126b11920 ---
+# uipc_ready() at uipc_ready+0x1f0/frame 0xfffffe0126b11920
+# sendfile_iodone() at sendfile_iodone+0x1ac/frame 0xfffffe0126b11960
+# vnode_pager_generic_getpages_done_async() at vnode_pager_generic_getpages_done_async+0x3a/frame 0xfffffe0126b11980
+# bufdone() at bufdone+0x6c/frame 0xfffffe0126b119f0
+# g_io_deliver() at g_io_deliver+0x25e/frame 0xfffffe0126b11a40
+# g_io_deliver() at g_io_deliver+0x25e/frame 0xfffffe0126b11a90
+# g_disk_done() at g_disk_done+0xed/frame 0xfffffe0126b11ad0
+# dadone() at dadone+0x603/frame 0xfffffe0126b11b20
+# xpt_done_process() at xpt_done_process+0x382/frame 0xfffffe0126b11b60
+# xpt_done_td() at xpt_done_td+0xf5/frame 0xfffffe0126b11bb0
+# fork_exit() at fork_exit+0x80/frame 0xfffffe0126b11bf0
+# fork_trampoline() at fork_trampoline+0xe/frame 0xfffffe0126b11bf0
+# --- trap 0, rip = 0, rsp = 0, rbp = 0 ---
+# KDB: enter: panic
+# [ thread pid 32 tid 100163 ]
+# Stopped at      kdb_enter+0x37: movq    $0,0x10c72c6(%rip)
+# db>
+
+# $FreeBSD$
+
+# Reproduced on r361889
+
+[ `uname -p` = "i386" ] && exit 0
+
+. ../default.cfg
+cat > /tmp/syzkaller13.c <<EOF
+// https://syzkaller.appspot.com/bug?id=8a63fce7c52d85d6fca9aca543ce5a77cdd15f25
+// autogenerated by syzkaller (https://github.com/google/syzkaller)
+// Reported-by: syzbot+6a689cc9c27bd265237a@syzkaller.appspotmail.com
+
+#define _GNU_SOURCE
+
+#include <sys/types.h>
+
+#include <dirent.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/stat.h>
+#include <sys/syscall.h>
+#include <sys/wait.h>
+#include <time.h>
+#include <unistd.h>
+
+static unsigned long long procid;
+
+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 use_temporary_dir(void)
+{
+  char tmpdir_template[] = "./syzkaller.XXXXXX";
+  char* tmpdir = mkdtemp(tmpdir_template);
+  if (!tmpdir)
+    exit(1);
+  if (chmod(tmpdir, 0777))
+    exit(1);
+  if (chdir(tmpdir))
+    exit(1);
+}
+
+static void remove_dir(const char* dir)
+{
+  DIR* dp;
+  struct dirent* ep;
+  dp = opendir(dir);
+  if (dp == NULL)
+    exit(1);
+  while ((ep = readdir(dp))) {
+    if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0)
+      continue;
+    char filename[FILENAME_MAX];
+    snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name);
+    struct stat st;
+    if (lstat(filename, &st))
+      exit(1);
+    if (S_ISDIR(st.st_mode)) {
+      remove_dir(filename);
+      continue;
+    }
+    if (unlink(filename))
+      exit(1);
+  }
+  closedir(dp);
+  if (rmdir(dir))
+    exit(1);
+}
+
+static void execute_one(void);
+
+#define WAIT_FLAGS 0
+
+static void loop(void)
+{
+  int iter;
+  for (iter = 0;; iter++) {
+    char cwdbuf[32];
+    sprintf(cwdbuf, "./%d", iter);
+    if (mkdir(cwdbuf, 0777))
+      exit(1);
+    int pid = fork();
+    if (pid < 0)
+      exit(1);
+    if (pid == 0) {
+      if (chdir(cwdbuf))
+        exit(1);
+      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;
+    }
+    remove_dir(cwdbuf);
+  }
+}
+
+uint64_t r[5] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff,
+                 0xffffffffffffffff, 0xffffffffffffffff};
+
+void execute_one(void)
+{
+  intptr_t res = 0;
+  memcpy((void*)0x20000100, "./file0\000", 8);
+  res = syscall(SYS_open, 0x20000100ul, 0x40000400000002c2ul, 0ul);
+  if (res != -1)
+    r[0] = res;
+  syscall(SYS_fcntl, r[0], 4ul, 0x10048ul);
+  *(uint64_t*)0x20000340 = 0x20000180;
+  *(uint64_t*)0x20000348 = 0x81700;
+  syscall(SYS_writev, r[0], 0x20000340ul, 0x1000000000000013ul);
+  res = syscall(SYS_socket, 2ul, 2ul, 0x88);
+  if (res != -1)
+    r[1] = res;
+  res = syscall(SYS_socketpair, 1ul, 1ul, 0, 0x20000000ul);
+  if (res != -1)
+    r[2] = *(uint32_t*)0x20000000;
+  res = syscall(SYS_dup2, r[2], r[1]);
+  if (res != -1)
+    r[3] = res;
+  memcpy((void*)0x20000140, "./file0\000", 8);
+  res = syscall(SYS_open, 0x20000140ul, 0ul, 0ul);
+  if (res != -1)
+    r[4] = res;
+  syscall(SYS_sendfile, r[4], r[3], 0ul, 1ul, 0ul, 0ul, 0ul);
+}
+int main(void)
+{
+  syscall(SYS_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x1012ul, -1, 0ul);
+  for (procid = 0; procid < 4; procid++) {
+    if (fork() == 0) {
+      use_temporary_dir();
+      loop();
+    }
+  }
+  sleep(1000000);
+  return 0;
+}
+EOF
+mycc -o /tmp/syzkaller13 -Wall -Wextra -O2 /tmp/syzkaller13.c -lpthread ||
+    exit 1
+
+(cd ../testcases/swap; ./swap -t 1m -i 20 -h > /dev/null 2>&1) &
+(cd /tmp; ./syzkaller13) &
+sleep 60
+pkill -9 syzkaller13 swap
+wait
+
+rm -f /tmp/syzkaller13 /tmp/syzkaller13.c /tmp/syzkaller13.core /tmp/file0
+exit 0



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?202006071215.057CFgsI046296>