[JFFS2] Check CRC32 on dirent and data nodes each time they're read

Also, make sure dirents are marked REF_UNCHECKED when we 'discover' them
through eraseblock summary.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

2 files changed, 38 insertions, 15 deletions

diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c
index 5351b34d5419..5ea4faafa2d3 100644
--- a/fs/jffs2/readinode.c
+++ b/fs/jffs2/readinode.c
@@ -116,19 +116,42 @@ static inline int read_direntry(struct jffs2_sb_info *c, struct jffs2_raw_node_r
                                 uint32_t *latest_mctime, uint32_t *mctime_ver)
 {
         struct jffs2_full_dirent *fd;
+        uint32_t crc;
 
-        /* The direntry nodes are checked during the flash scanning */
-        BUG_ON(ref_flags(ref) == REF_UNCHECKED);
         /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */
         BUG_ON(ref_obsolete(ref));
 
-        /* Sanity check */
-        if (unlikely(PAD((rd->nsize + sizeof(*rd))) != PAD(je32_to_cpu(rd->totlen)))) {
-                JFFS2_ERROR("illegal nsize in node at %#08x: nsize %#02x, totlen %#04x\n",
-                       ref_offset(ref), rd->nsize, je32_to_cpu(rd->totlen));
+        crc = crc32(0, rd, sizeof(*rd) - 8);
+        if (unlikely(crc != je32_to_cpu(rd->node_crc))) {
+                JFFS2_NOTICE("header CRC failed on dirent node at %#08x: read %#08x, calculated %#08x\n",
+                             ref_offset(ref), je32_to_cpu(rd->node_crc), crc);
                 return 1;
         }
 
+        /* If we've never checked the CRCs on this node, check them now */
+        if (ref_flags(ref) == REF_UNCHECKED) {
+                struct jffs2_eraseblock *jeb;
+                int len;
+
+                /* Sanity check */
+                if (unlikely(PAD((rd->nsize + sizeof(*rd))) != PAD(je32_to_cpu(rd->totlen)))) {
+                        JFFS2_ERROR("illegal nsize in node at %#08x: nsize %#02x, totlen %#04x\n",
+                                    ref_offset(ref), rd->nsize, je32_to_cpu(rd->totlen));
+                        return 1;
+                }
+
+                jeb = &c->blocks[ref->flash_offset / c->sector_size];
+                len = ref_totlen(c, jeb, ref);
+
+                spin_lock(&c->erase_completion_lock);
+                jeb->used_size += len;
+                jeb->unchecked_size -= len;
+                c->used_size += len;
+                c->unchecked_size -= len;
+                ref->flash_offset = ref_offset(ref) | REF_PRISTINE;
+                spin_unlock(&c->erase_completion_lock);
+        }
+
         fd = jffs2_alloc_full_dirent(rd->nsize + 1);
         if (unlikely(!fd))
                 return -ENOMEM;
@@ -198,10 +221,18 @@ static inline int read_dnode(struct jffs2_sb_info *c, struct jffs2_raw_node_ref
         struct jffs2_tmp_dnode_info *tn;
         uint32_t len, csize;
         int ret = 1;
+        uint32_t crc;
 
         /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */
         BUG_ON(ref_obsolete(ref));
 
+        crc = crc32(0, rd, sizeof(*rd) - 8);
+        if (unlikely(crc != je32_to_cpu(rd->node_crc))) {
+                JFFS2_NOTICE("node CRC failed on dnode at %#08x: read %#08x, calculated %#08x\n",
+                             ref_offset(ref), je32_to_cpu(rd->node_crc), crc);
+                return 1;
+        }
+
         tn = jffs2_alloc_tmp_dnode_info();
         if (!tn) {
                 JFFS2_ERROR("failed to allocate tn (%zu bytes).\n", sizeof(*tn));
@@ -213,14 +244,6 @@ static inline int read_dnode(struct jffs2_sb_info *c, struct jffs2_raw_node_ref
 
         /* If we've never checked the CRCs on this node, check them now */
         if (ref_flags(ref) == REF_UNCHECKED) {
-                uint32_t crc;
-
-                crc = crc32(0, rd, sizeof(*rd) - 8);
-                if (unlikely(crc != je32_to_cpu(rd->node_crc))) {
-                        JFFS2_NOTICE("header CRC failed on node at %#08x: read %#08x, calculated %#08x\n",
-                                        ref_offset(ref), je32_to_cpu(rd->node_crc), crc);
-                        goto free_out;
-                }
 
                 /* Sanity checks */
                 if (unlikely(je32_to_cpu(rd->offset) > je32_to_cpu(rd->isize)) ||
diff --git a/fs/jffs2/summary.c b/fs/jffs2/summary.c
index 51bf1654ce3b..0b02fc79e4d1 100644
--- a/fs/jffs2/summary.c
+++ b/fs/jffs2/summary.c
@@ -453,7 +453,7 @@ static int jffs2_sum_process_sum_data(struct jffs2_sb_info *c, struct jffs2_eras
                                         return -ENOMEM;
                                 }
 
-                                fd->raw = sum_link_node_ref(c, jeb,  je32_to_cpu(spd->offset) | REF_PRISTINE,
+                                fd->raw = sum_link_node_ref(c, jeb,  je32_to_cpu(spd->offset) | REF_UNCHECKED,
                                                             PAD(je32_to_cpu(spd->totlen)), ic);
 
                                 fd->next = NULL;