grub: clean up CVE patches

Clean up several patches introduced in commit 6732918498 ("grub:fix
several CVEs in grub 2.04").

1) Add CVE tags to individual patches.
2) Rename upstream patches and prefix them with CVE tags.
3) Add description of reference to upstream patch.

Signed-off-by: Yongxin Liu <yongxin.liu@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 287 insertions, 0 deletions

diff --git a/meta/recipes-bsp/grub/files/lvm-Add-LVM-cache-logical-volume-handling.patch b/meta/recipes-bsp/grub/files/lvm-Add-LVM-cache-logical-volume-handling.patch
new file mode 100644
index 0000000000..2b8157f592
--- /dev/null
+++ b/meta/recipes-bsp/grub/files/lvm-Add-LVM-cache-logical-volume-handling.patch
@@ -0,0 +1,287 @@
+From 8eb02bcb5897b238b29ff762402bb0c3028f0eab Mon Sep 17 00:00:00 2001
+From: Michael Chang <mchang@suse.com>
+Date: Thu, 19 Mar 2020 13:56:13 +0800
+Subject: [PATCH 3/9] lvm: Add LVM cache logical volume handling
+
+The LVM cache logical volume is the logical volume consisting of the original
+and the cache pool logical volume. The original is usually on a larger and
+slower storage device while the cache pool is on a smaller and faster one. The
+performance of the original volume can be improved by storing the frequently
+used data on the cache pool to utilize the greater performance of faster
+device.
+
+The default cache mode "writethrough" ensures that any data written will be
+stored both in the cache and on the origin LV, therefore grub can be straight
+to read the original lv as no data loss is guarenteed.
+
+The second cache mode is "writeback", which delays writing from the cache pool
+back to the origin LV to have increased performance. The drawback is potential
+data loss if losing the associated cache device.
+
+During the boot time grub reads the LVM offline i.e. LVM volumes are not
+activated and mounted, hence it should be fine to read directly from original
+lv since all cached data should have been flushed back in the process of taking
+it offline.
+
+It is also not much helpful to the situation by adding fsync calls to the
+install code. The fsync did not force to write back dirty cache to the original
+device and rather it would update associated cache metadata to complete the
+write transaction with the cache device. IOW the writes to cached blocks still
+go only to the cache device.
+
+To write back dirty cache, as LVM cache did not support dirty cache flush per
+block range, there'no way to do it for file. On the other hand the "cleaner"
+policy is implemented and can be used to write back "all" dirty blocks in a
+cache, which effectively drain all dirty cache gradually to attain and last in
+the "clean" state, which can be useful for shrinking or decommissioning a
+cache. The result and effect is not what we are looking for here.
+
+In conclusion, as it seems no way to enforce file writes to the original
+device, grub may suffer from power failure as it cannot assemble the cache
+device and read the dirty data from it. However since the case is only
+applicable to writeback mode which is sensitive to data lost in nature, I'd
+still like to propose my (relatively simple) patch and treat reading dirty
+cache as improvement.
+
+Upstream-Status: Backport [commit 0454b0445393aafc5600e92ef0c39494e333b135
+from https://git.savannah.gnu.org/git/grub.git]
+
+Signed-off-by: Michael Chang <mchang@suse.com>
+Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
+Signed-off-by: Yongxin Liu <yongxin.liu@windriver.com>
+---
+ grub-core/disk/lvm.c | 190 +++++++++++++++++++++++++++++++++++++++++++++++++++
+ 1 file changed, 190 insertions(+)
+
+diff --git a/grub-core/disk/lvm.c b/grub-core/disk/lvm.c
+index 7b265c7..dc6b83b 100644
+--- a/grub-core/disk/lvm.c
++++ b/grub-core/disk/lvm.c
+@@ -33,6 +33,14 @@
+ 
+ GRUB_MOD_LICENSE ("GPLv3+");
+ 
++struct cache_lv
++{
++  struct grub_diskfilter_lv *lv;
++  char *cache_pool;
++  char *origin;
++  struct cache_lv *next;
++};
++
+ 
+ /* Go the string STR and return the number after STR.  *P will point
+    at the number.  In case STR is not found, *P will be NULL and the
+@@ -95,6 +103,34 @@ grub_lvm_check_flag (char *p, const char *str, const char *flag)
+     }
+ }
+ 
++static void
++grub_lvm_free_cache_lvs (struct cache_lv *cache_lvs)
++{
++  struct cache_lv *cache;
++
++  while ((cache = cache_lvs))
++    {
++      cache_lvs = cache_lvs->next;
++
++      if (cache->lv)
++	{
++	  unsigned int i;
++
++	  for (i = 0; i < cache->lv->segment_count; ++i)
++	    if (cache->lv->segments)
++	      grub_free (cache->lv->segments[i].nodes);
++	  grub_free (cache->lv->segments);
++	  grub_free (cache->lv->fullname);
++	  grub_free (cache->lv->idname);
++	  grub_free (cache->lv->name);
++	}
++      grub_free (cache->lv);
++      grub_free (cache->origin);
++      grub_free (cache->cache_pool);
++      grub_free (cache);
++    }
++}
++
+ static struct grub_diskfilter_vg * 
+ grub_lvm_detect (grub_disk_t disk,
+ 		 struct grub_diskfilter_pv_id *id,
+@@ -242,6 +278,8 @@ grub_lvm_detect (grub_disk_t disk,
+ 
+   if (! vg)
+     {
++      struct cache_lv *cache_lvs = NULL;
++
+       /* First time we see this volume group. We've to create the
+ 	 whole volume group structure. */
+       vg = grub_malloc (sizeof (*vg));
+@@ -671,6 +709,106 @@ grub_lvm_detect (grub_disk_t disk,
+ 			  seg->nodes[seg->node_count - 1].name = tmp;
+ 			}
+ 		    }
++		  else if (grub_memcmp (p, "cache\"",
++				   sizeof ("cache\"") - 1) == 0)
++		    {
++		      struct cache_lv *cache = NULL;
++
++		      char *p2, *p3;
++		      grub_size_t sz;
++
++		      cache = grub_zalloc (sizeof (*cache));
++		      if (!cache)
++			goto cache_lv_fail;
++		      cache->lv = grub_zalloc (sizeof (*cache->lv));
++		      if (!cache->lv)
++			goto cache_lv_fail;
++		      grub_memcpy (cache->lv, lv, sizeof (*cache->lv));
++
++		      if (lv->fullname)
++			{
++			  cache->lv->fullname = grub_strdup (lv->fullname);
++			  if (!cache->lv->fullname)
++			    goto cache_lv_fail;
++			}
++		      if (lv->idname)
++			{
++			  cache->lv->idname = grub_strdup (lv->idname);
++			  if (!cache->lv->idname)
++			    goto cache_lv_fail;
++			}
++		      if (lv->name)
++			{
++			  cache->lv->name = grub_strdup (lv->name);
++			  if (!cache->lv->name)
++			    goto cache_lv_fail;
++			}
++
++		      skip_lv = 1;
++
++		      p2 = grub_strstr (p, "cache_pool = \"");
++		      if (!p2)
++			goto cache_lv_fail;
++
++		      p2 = grub_strchr (p2, '"');
++		      if (!p2)
++			goto cache_lv_fail;
++
++		      p3 = ++p2;
++		      p3 = grub_strchr (p3, '"');
++		      if (!p3)
++			goto cache_lv_fail;
++
++		      sz = p3 - p2;
++
++		      cache->cache_pool = grub_malloc (sz + 1);
++		      if (!cache->cache_pool)
++			goto cache_lv_fail;
++		      grub_memcpy (cache->cache_pool, p2, sz);
++		      cache->cache_pool[sz] = '\0';
++
++		      p2 = grub_strstr (p, "origin = \"");
++		      if (!p2)
++			goto cache_lv_fail;
++
++		      p2 = grub_strchr (p2, '"');
++		      if (!p2)
++			goto cache_lv_fail;
++
++		      p3 = ++p2;
++		      p3 = grub_strchr (p3, '"');
++		      if (!p3)
++			goto cache_lv_fail;
++
++		      sz = p3 - p2;
++
++		      cache->origin = grub_malloc (sz + 1);
++		      if (!cache->origin)
++			goto cache_lv_fail;
++		      grub_memcpy (cache->origin, p2, sz);
++		      cache->origin[sz] = '\0';
++
++		      cache->next = cache_lvs;
++		      cache_lvs = cache;
++		      break;
++
++		    cache_lv_fail:
++		      if (cache)
++			{
++			  grub_free (cache->origin);
++			  grub_free (cache->cache_pool);
++			  if (cache->lv)
++			    {
++			      grub_free (cache->lv->fullname);
++			      grub_free (cache->lv->idname);
++			      grub_free (cache->lv->name);
++			    }
++			  grub_free (cache->lv);
++			  grub_free (cache);
++			}
++		      grub_lvm_free_cache_lvs (cache_lvs);
++		      goto fail4;
++		    }
+ 		  else
+ 		    {
+ #ifdef GRUB_UTIL
+@@ -747,6 +885,58 @@ grub_lvm_detect (grub_disk_t disk,
+ 	      }
+ 	
+       }
++
++      {
++	struct cache_lv *cache;
++
++	for (cache = cache_lvs; cache; cache = cache->next)
++	  {
++	    struct grub_diskfilter_lv *lv;
++
++	    for (lv = vg->lvs; lv; lv = lv->next)
++	      if (grub_strcmp (lv->name, cache->origin) == 0)
++		break;
++	    if (lv)
++	      {
++		cache->lv->segments = grub_malloc (lv->segment_count * sizeof (*lv->segments));
++		if (!cache->lv->segments)
++		  {
++		    grub_lvm_free_cache_lvs (cache_lvs);
++		    goto fail4;
++		  }
++		grub_memcpy (cache->lv->segments, lv->segments, lv->segment_count * sizeof (*lv->segments));
++
++		for (i = 0; i < lv->segment_count; ++i)
++		  {
++		    struct grub_diskfilter_node *nodes = lv->segments[i].nodes;
++		    grub_size_t node_count = lv->segments[i].node_count;
++
++		    cache->lv->segments[i].nodes = grub_malloc (node_count * sizeof (*nodes));
++		    if (!cache->lv->segments[i].nodes)
++		      {
++			for (j = 0; j < i; ++j)
++			  grub_free (cache->lv->segments[j].nodes);
++			grub_free (cache->lv->segments);
++			cache->lv->segments = NULL;
++			grub_lvm_free_cache_lvs (cache_lvs);
++			goto fail4;
++		      }
++		    grub_memcpy (cache->lv->segments[i].nodes, nodes, node_count * sizeof (*nodes));
++		  }
++
++		if (cache->lv->segments)
++		  {
++		    cache->lv->segment_count = lv->segment_count;
++		    cache->lv->vg = vg;
++		    cache->lv->next = vg->lvs;
++		    vg->lvs = cache->lv;
++		    cache->lv = NULL;
++		  }
++	      }
++	  }
++      }
++
++      grub_lvm_free_cache_lvs (cache_lvs);
+       if (grub_diskfilter_vg_register (vg))
+ 	goto fail4;
+     }
+-- 
+2.14.4
+