Merge remote-tracking branch 'riku/linux-user-for-upstream' into staging

* riku/linux-user-for-upstream:
  linux-user: Clarify "Unable to reserve guest address space" error
  linux-user: fix emulation of getdents
  linux-user: arg_table need not have global scope

linux-user/main.c

@@ -3222,7 +3222,7 @@ struct qemu_argument {
     const char *help;
 };
 
-struct qemu_argument arg_table[] = {
+static const struct qemu_argument arg_table[] = {
     {"h",          "",                 false, handle_arg_help,
      "",           "print this help"},
     {"g",          "QEMU_GDB",         true,  handle_arg_gdb,
@@ -3264,7 +3264,7 @@ struct qemu_argument arg_table[] = {
 
 static void usage(void)
 {
-    struct qemu_argument *arginfo;
+    const struct qemu_argument *arginfo;
     int maxarglen;
     int maxenvlen;
 
@@ -3330,7 +3330,7 @@ static int parse_args(int argc, char **argv)
 {
     const char *r;
     int optind;
-    struct qemu_argument *arginfo;
+    const struct qemu_argument *arginfo;
 
     for (arginfo = arg_table; arginfo->handle_opt != NULL; arginfo++) {
         if (arginfo->env == NULL) {
@@ -3519,7 +3519,10 @@ int main(int argc, char **argv, char **envp)
         guest_base = init_guest_space(guest_base, reserved_va, 0,
                                       have_guest_base);
         if (guest_base == (unsigned long)-1) {
-            fprintf(stderr, "Unable to reserve guest address space\n");
+            fprintf(stderr, "Unable to reserve 0x%lx bytes of virtual address "
+                    "space for use as guest address space (check your virtual "
+                    "memory ulimit setting or reserve less using -R option)\n",
+                    reserved_va);
             exit(1);
         }
 

linux-user/syscall.c

@@ -7025,15 +7025,14 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
 		tde = target_dirp;
                 while (len > 0) {
                     reclen = de->d_reclen;
-		    treclen = reclen - (2 * (sizeof(long) - sizeof(abi_long)));
+                    tnamelen = reclen - offsetof(struct linux_dirent, d_name);
+                    assert(tnamelen >= 0);
+                    treclen = tnamelen + offsetof(struct target_dirent, d_name);
+                    assert(count1 + treclen <= count);
                     tde->d_reclen = tswap16(treclen);
                     tde->d_ino = tswapal(de->d_ino);
                     tde->d_off = tswapal(de->d_off);
-		    tnamelen = treclen - (2 * sizeof(abi_long) + 2);
-		    if (tnamelen > 256)
-                        tnamelen = 256;
-                    /* XXX: may not be correct */
-                    pstrcpy(tde->d_name, tnamelen, de->d_name);
+                    memcpy(tde->d_name, de->d_name, tnamelen);
                     de = (struct linux_dirent *)((char *)de + reclen);
                     len -= reclen;
                     tde = (struct target_dirent *)((char *)tde + treclen);

linux-user/syscall_defs.h

@@ -255,10 +255,10 @@ struct kernel_statfs {
 };
 
 struct target_dirent {
-	abi_long	d_ino;
-	abi_long	d_off;
-	unsigned short	d_reclen;
-	char		d_name[256]; /* We must not include limits.h! */
+        abi_long        d_ino;
+        abi_long        d_off;
+        unsigned short  d_reclen;
+        char            d_name[];
 };
 
 struct target_dirent64 {