X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;f=src%2Flaunch.c;h=a93ef0bd49053370421f405bac84351740b1a0a1;hb=3f54bd02fcf540f9b4b6edc93f3b6b9c7ba136bd;hp=11d1acffd8a4620f0d401c0779cdebd3b8384a7a;hpb=f3673343564d885919ee01591f9f730d1be33631;p=libguestfs.git

diff --git a/src/launch.c b/src/launch.c
index 11d1acf..a93ef0b 100644
--- a/src/launch.c
+++ b/src/launch.c
@@ -105,9 +105,9 @@ free_regexps (void)
 }
 #endif
 
-/* Add a string to the current command line. */
+/* Functions to add a string to the current command line. */
 static void
-incr_cmdline_size (guestfs_h *g)
+alloc_cmdline (guestfs_h *g)
 {
   if (g->cmdline == NULL) {
     /* g->cmdline[0] is reserved for argv[0], set in guestfs_launch. */
@@ -115,7 +115,12 @@ incr_cmdline_size (guestfs_h *g)
     g->cmdline = safe_malloc (g, sizeof (char *));
     g->cmdline[0] = NULL;
   }
+}
 
+static void
+incr_cmdline_size (guestfs_h *g)
+{
+  alloc_cmdline (g);
   g->cmdline_size++;
   g->cmdline = safe_realloc (g, g->cmdline, sizeof (char *) * g->cmdline_size);
 }
@@ -160,11 +165,7 @@ guestfs__debug_cmdline (guestfs_h *g)
   size_t i;
   char **r;
 
-  if (g->cmdline == NULL) {
-    r = safe_malloc (g, sizeof (char *) * 1);
-    r[0] = NULL;
-    return r;
-  }
+  alloc_cmdline (g);
 
   r = safe_malloc (g, sizeof (char *) * (g->cmdline_size + 1));
   r[0] = safe_strdup (g, g->qemu); /* g->cmdline[0] is always NULL */
@@ -512,8 +513,24 @@ launch_appliance (guestfs_h *g)
     /* Set up the full command line.  Do this in the subprocess so we
      * don't need to worry about cleaning up.
      */
+
+    /* Set g->cmdline[0] to the name of the qemu process.  However
+     * it is possible that no g->cmdline has been allocated yet so
+     * we must do that first.
+     */
+    alloc_cmdline (g);
     g->cmdline[0] = g->qemu;
 
+    /* CVE-2011-4127 mitigation: Disable SCSI ioctls on virtio-blk
+     * devices.  The -global option must exist, but you can pass any
+     * strings to it so we don't need to check for the specific virtio
+     * feature.
+     */
+    if (qemu_supports (g, "-global")) {
+      add_cmdline (g, "-global");
+      add_cmdline (g, "virtio-blk-pci.scsi=off");
+    }
+
     if (qemu_supports (g, "-nodefconfig"))
       add_cmdline (g, "-nodefconfig");
 
@@ -523,7 +540,19 @@ launch_appliance (guestfs_h *g)
      */
     if (qemu_supports (g, "-machine")) {
       add_cmdline (g, "-machine");
+#if QEMU_MACHINE_TYPE_IS_BROKEN
+      /* Workaround for qemu 0.15: We have to add the '[type=]pc'
+       * since there is no default.  This is not a permanent solution
+       * because this only works on PC-like hardware.  Other platforms
+       * like ppc would need a different machine type.
+       *
+       * This bug is fixed in qemu commit 2645c6dcaf6ea2a51a, and was
+       * not a problem in qemu < 0.15.
+       */
+      add_cmdline (g, "pc,accel=kvm:tcg");
+#else
       add_cmdline (g, "accel=kvm:tcg");
+#endif
     } else {
       /* qemu sometimes needs this option to enable hardware
        * virtualization, but some versions of 'qemu-kvm' will use KVM
@@ -607,6 +636,7 @@ launch_appliance (guestfs_h *g)
     "console=ttyS0 "   /* serial console */				\
     "udevtimeout=300 " /* good for very slow systems (RHBZ#480319) */	\
     "noapic "          /* workaround for RHBZ#502058 - ok if not SMP */ \
+    "no_timer_check "  /* fix for RHBZ#502058 */                        \
     "acpi=off "        /* we don't need ACPI, turn it off */		\
     "printk.time=1 "   /* display timestamp before kernel messages */   \
     "cgroup_disable=memory " /* saves us about 5 MB of RAM */
@@ -1083,7 +1113,8 @@ test_qemu (guestfs_h *g)
    * probably indicates that the qemu binary is missing.
    */
   if (test_qemu_cmd (g, cmd, &g->qemu_help) == -1) {
-    perrorf (g, _("%s: command failed: If qemu is located on a non-standard path, try setting the LIBGUESTFS_QEMU environment variable."), cmd);
+    error (g, _("command failed: %s\n\nIf qemu is located on a non-standard path, try setting the LIBGUESTFS_QEMU\nenvironment variable.  There may also be errors printed above."),
+           cmd);
     return -1;
   }