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Subject: svn commit: r361890 - user/pho/stress2/misc
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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

From owner-svn-src-user@freebsd.org  Tue Jun  9 06:48:26 2020
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Subject: svn commit: r361961 - user/pho/stress2/misc
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Author: pho
Date: Tue Jun  9 06:48:25 2020
New Revision: 361961
URL: https://svnweb.freebsd.org/changeset/base/361961

Log:
  Added a syzkaller reproducer.

Added:
  user/pho/stress2/misc/syzkaller14.sh   (contents, props changed)

Added: user/pho/stress2/misc/syzkaller14.sh
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ user/pho/stress2/misc/syzkaller14.sh	Tue Jun  9 06:48:25 2020	(r361961)
@@ -0,0 +1,297 @@
+#!/bin/sh
+
+# panic: mtx_lock() of spin mutex (null) @ ../../../kern/uipc_ktls.c:1034
+# cpuid = 5
+# time = 1591684934
+# KDB: stack backtrace:
+# db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe013a91b6c0
+# vpanic() at vpanic+0x182/frame 0xfffffe013a91b710
+# panic() at panic+0x43/frame 0xfffffe013a91b770
+# __mtx_lock_flags() at __mtx_lock_flags+0x13c/frame 0xfffffe013a91b7c0
+# ktls_get_rx_mode() at ktls_get_rx_mode+0x4e/frame 0xfffffe013a91b7f0
+# tcp_default_ctloutput() at tcp_default_ctloutput+0x800/frame 0xfffffe013a91b960
+# tcp_ctloutput() at tcp_ctloutput+0x1f5/frame 0xfffffe013a91b9d0
+# sogetopt() at sogetopt+0x101/frame 0xfffffe013a91ba40
+# kern_getsockopt() at kern_getsockopt+0xb4/frame 0xfffffe013a91baa0
+# sys_getsockopt() at sys_getsockopt+0x52/frame 0xfffffe013a91bad0
+# amd64_syscall() at amd64_syscall+0x159/frame 0xfffffe013a91bbf0
+# fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe013a91bbf0
+# --- syscall (0, FreeBSD ELF64, nosys), rip = 0x80045446a, rsp = 0x7fffdffdcf88, rbp = 0x7fffdffdcfc0 ---
+# KDB: enter: panic
+# [ thread pid 5313 tid 101679 ]
+# Stopped at      kdb_enter+0x37: movq    $0,0x10c7fa6(%rip)
+# db> x/s version
+# version:        FreeBSD 13.0-CURRENT #0 r361886: Tue Jun  9 08:32:24 CEST 2020\012    pho@t2.osted.lan:/usr/src/sys/amd64/compile/KTLS\012
+# db>
+
+# $FreeBSD$
+
+# Reproduced on r361886 with "options KERN_TLS"
+
+[ `uname -p` = "i386" ] && exit 0
+
+. ../default.cfg
+cat > /tmp/syzkaller14.c <<EOF
+// https://syzkaller.appspot.com/bug?id=d50164ce557a20a785510aac5d6f104d8a62e779
+// autogenerated by syzkaller (https://github.com/google/syzkaller)
+// Reported-by: syzbot+a8829e888a93a4a04619@syzkaller.appspotmail.com
+
+#define _GNU_SOURCE
+
+#include <sys/types.h>
+
+#include <errno.h>
+#include <pthread.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 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 thread_start(void* (*fn)(void*), void* arg)
+{
+  pthread_t th;
+  pthread_attr_t attr;
+  pthread_attr_init(&attr);
+  pthread_attr_setstacksize(&attr, 128 << 10);
+  int i;
+  for (i = 0; i < 100; i++) {
+    if (pthread_create(&th, &attr, fn, arg) == 0) {
+      pthread_attr_destroy(&attr);
+      return;
+    }
+    if (errno == EAGAIN) {
+      usleep(50);
+      continue;
+    }
+    break;
+  }
+  exit(1);
+}
+
+typedef struct {
+  pthread_mutex_t mu;
+  pthread_cond_t cv;
+  int state;
+} event_t;
+
+static void event_init(event_t* ev)
+{
+  if (pthread_mutex_init(&ev->mu, 0))
+    exit(1);
+  if (pthread_cond_init(&ev->cv, 0))
+    exit(1);
+  ev->state = 0;
+}
+
+static void event_reset(event_t* ev)
+{
+  ev->state = 0;
+}
+
+static void event_set(event_t* ev)
+{
+  pthread_mutex_lock(&ev->mu);
+  if (ev->state)
+    exit(1);
+  ev->state = 1;
+  pthread_mutex_unlock(&ev->mu);
+  pthread_cond_broadcast(&ev->cv);
+}
+
+static void event_wait(event_t* ev)
+{
+  pthread_mutex_lock(&ev->mu);
+  while (!ev->state)
+    pthread_cond_wait(&ev->cv, &ev->mu);
+  pthread_mutex_unlock(&ev->mu);
+}
+
+static int event_isset(event_t* ev)
+{
+  pthread_mutex_lock(&ev->mu);
+  int res = ev->state;
+  pthread_mutex_unlock(&ev->mu);
+  return res;
+}
+
+static int event_timedwait(event_t* ev, uint64_t timeout)
+{
+  uint64_t start = current_time_ms();
+  uint64_t now = start;
+  pthread_mutex_lock(&ev->mu);
+  for (;;) {
+    if (ev->state)
+      break;
+    uint64_t remain = timeout - (now - start);
+    struct timespec ts;
+    ts.tv_sec = remain / 1000;
+    ts.tv_nsec = (remain % 1000) * 1000 * 1000;
+    pthread_cond_timedwait(&ev->cv, &ev->mu, &ts);
+    now = current_time_ms();
+    if (now - start > timeout)
+      break;
+  }
+  int res = ev->state;
+  pthread_mutex_unlock(&ev->mu);
+  return res;
+}
+
+struct thread_t {
+  int created, call;
+  event_t ready, done;
+};
+
+static struct thread_t threads[16];
+static void execute_call(int call);
+static int running;
+
+static void* thr(void* arg)
+{
+  struct thread_t* th = (struct thread_t*)arg;
+  for (;;) {
+    event_wait(&th->ready);
+    event_reset(&th->ready);
+    execute_call(th->call);
+    __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED);
+    event_set(&th->done);
+  }
+  return 0;
+}
+
+static void execute_one(void)
+{
+  int i, call, thread;
+  int collide = 0;
+again:
+  for (call = 0; call < 3; call++) {
+    for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0]));
+         thread++) {
+      struct thread_t* th = &threads[thread];
+      if (!th->created) {
+        th->created = 1;
+        event_init(&th->ready);
+        event_init(&th->done);
+        event_set(&th->done);
+        thread_start(thr, th);
+      }
+      if (!event_isset(&th->done))
+        continue;
+      event_reset(&th->done);
+      th->call = call;
+      __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED);
+      event_set(&th->ready);
+      if (collide && (call % 2) == 0)
+        break;
+      event_timedwait(&th->done, 45);
+      break;
+    }
+  }
+  for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++)
+    sleep_ms(1);
+  if (!collide) {
+    collide = 1;
+    goto again;
+  }
+}
+
+static void execute_one(void);
+
+#define WAIT_FLAGS 0
+
+static void loop(void)
+{
+  int iter;
+  for (iter = 0;; 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;
+    }
+  }
+}
+
+uint64_t r[1] = {0xffffffffffffffff};
+
+void execute_call(int call)
+{
+  intptr_t res = 0;
+  switch (call) {
+  case 0:
+    res = syscall(SYS_socket, 0x1cul, 1ul, 0);
+    if (res != -1)
+      r[0] = res;
+    break;
+  case 1:
+    syscall(SYS_getsockopt, r[0], 6, 0x2a, 0ul, 0ul);
+    break;
+  case 2:
+    syscall(SYS_listen, r[0], 1);
+    break;
+  }
+}
+int main(void)
+{
+  syscall(SYS_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x1012ul, -1, 0ul);
+  for (procid = 0; procid < 4; procid++) {
+    if (fork() == 0) {
+      loop();
+    }
+  }
+  sleep(1000000);
+  return 0;
+}
+EOF
+mycc -o /tmp/syzkaller14 -Wall -Wextra -O2 /tmp/syzkaller14.c -lpthread ||
+    exit 1
+
+(cd /tmp; ./syzkaller14) &
+sleep 60
+pkill -9 syzkaller14
+wait
+
+rm -f /tmp/syzkaller14 /tmp/syzkaller14.c /tmp/syzkaller14.core
+exit 0