disk: Check if returned pointer for allocated memory is NULL

When using grub_malloc(), grub_zalloc() or grub_calloc(), these functions can
fail if we are out of memory. After allocating memory we should check if these
functions returned NULL and handle this error if they did.

On the occasion make a NULL check in ATA code more obvious.

Signed-off-by: Alec Brown <alec.r.brown@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

grub-core/disk/ata.c

@@ -112,10 +112,10 @@ grub_ata_identify (struct grub_ata *dev)
     return grub_atapi_identify (dev);
 
   info64 = grub_malloc (GRUB_DISK_SECTOR_SIZE);
+  if (info64 == NULL)
+    return grub_errno;
   info32 = (grub_uint32_t *) info64;
   info16 = (grub_uint16_t *) info64;
-  if (! info16)
-    return grub_errno;
 
   grub_memset (&parms, 0, sizeof (parms));
   parms.buffer = info16;

grub-core/disk/ieee1275/obdisk.c

@@ -423,6 +423,12 @@ canonicalise_disk (const char *devname)
 	}
 
       real_canon = grub_malloc (real_unit_str_len);
+      if (real_canon == NULL)
+	{
+	  grub_free (parent);
+	  grub_print_error ();
+	  return NULL;
+	}
 
       grub_snprintf (real_canon, real_unit_str_len, "%s/disk@%s",
                      op->name, real_unit_address);

grub-core/disk/ldm.c

@@ -292,6 +292,12 @@ make_vg (grub_disk_t disk,
 	    }
 
 	  pv->id.uuid = grub_malloc (sz);
+	  if (pv->id.uuid == NULL)
+	    {
+	      grub_free (pv->internal_id);
+	      grub_free (pv);
+	      goto fail2;
+	    }
 	  grub_memcpy (pv->id.uuid, ptr + 1, pv->id.uuidlen);
 	  pv->id.uuid[pv->id.uuidlen] = 0;
 

grub-core/disk/lvm.c

@@ -370,6 +370,8 @@ grub_lvm_detect (grub_disk_t disk,
 		break;
 
 	      pv = grub_zalloc (sizeof (*pv));
+	      if (pv == NULL)
+		goto fail4;
 	      q = p;
 	      while (*q != ' ' && q < mda_end)
 		q++;
@@ -379,6 +381,8 @@ grub_lvm_detect (grub_disk_t disk,
 
 	      s = q - p;
 	      pv->name = grub_malloc (s + 1);
+	      if (pv->name == NULL)
+		goto pvs_fail_noname;
 	      grub_memcpy (pv->name, p, s);
 	      pv->name[s] = '\0';
 
@@ -451,6 +455,8 @@ grub_lvm_detect (grub_disk_t disk,
 		break;
 
 	      lv = grub_zalloc (sizeof (*lv));
+	      if (lv == NULL)
+		goto fail4;
 
 	      q = p;
 	      while (*q != ' ' && q < mda_end)
@@ -545,6 +551,8 @@ grub_lvm_detect (grub_disk_t disk,
 		  goto lvs_fail;
 		}
 	      lv->segments = grub_calloc (lv->segment_count, sizeof (*seg));
+	      if (lv->segments == NULL)
+		goto lvs_fail;
 	      seg = lv->segments;
 
 	      for (i = 0; i < lv->segment_count; i++)
@@ -612,6 +620,8 @@ grub_lvm_detect (grub_disk_t disk,
 
 		      seg->nodes = grub_calloc (seg->node_count,
 						sizeof (*stripe));
+		      if (seg->nodes == NULL)
+			goto lvs_segment_fail;
 		      stripe = seg->nodes;
 
 		      p = grub_strstr (p, "stripes = [");
@@ -672,6 +682,8 @@ grub_lvm_detect (grub_disk_t disk,
 			}
 
 		      seg->nodes = grub_calloc (seg->node_count, sizeof (seg->nodes[0]));
+		      if (seg->nodes == NULL)
+			goto lvs_segment_fail;
 
 		      p = grub_strstr (p, "mirrors = [");
 		      if (p == NULL)
@@ -760,6 +772,8 @@ grub_lvm_detect (grub_disk_t disk,
 			}
 
 		      seg->nodes = grub_calloc (seg->node_count, sizeof (seg->nodes[0]));
+		      if (seg->nodes == NULL)
+			goto lvs_segment_fail;
 
 		      p = grub_strstr (p, "raids = [");
 		      if (p == NULL)

grub-core/disk/memdisk.c

@@ -103,6 +103,8 @@ GRUB_MOD_INIT(memdisk)
 	    return;
 	  }
 	memdisk_addr = grub_malloc (memdisk_size);
+	if (memdisk_addr == NULL)
+	  return;
 
 	grub_dprintf ("memdisk", "Copying memdisk image to dynamic memory\n");
 	grub_memmove (memdisk_addr, memdisk_orig_addr, memdisk_size);