[JFFS2] Better fix for all-zero node headers

No need to check for all-zero header since the header cannot
be zero due to other checks.

Replace the all-zero header check in readinode.c with a
check for the magic word.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

2 files changed, 5 insertions, 15 deletions

diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c
index 49d4b0a67c55..b09fa23abe53 100644
--- a/fs/jffs2/readinode.c
+++ b/fs/jffs2/readinode.c
@@ -1054,10 +1054,10 @@ static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_inf
                         jffs2_mark_node_obsolete(c, ref);
                         goto cont;
                 }
-                /* Due to poor choice of crc32 seed, an all-zero node will have a correct CRC */
-                if (!je32_to_cpu(node->u.hdr_crc) && !je16_to_cpu(node->u.nodetype) &&
-                    !je16_to_cpu(node->u.magic) && !je32_to_cpu(node->u.totlen)) {
-                        JFFS2_NOTICE("All zero node header at %#08x.\n", ref_offset(ref));
+                if (je16_to_cpu(node->u.magic) != JFFS2_MAGIC_BITMASK) {
+                        /* Not a JFFS2 node, whinge and move on */
+                        JFFS2_NOTICE("Wrong magic bitmask 0x%04x in node header at %#08x.\n",
+                                     je16_to_cpu(node->u.magic), ref_offset(ref));
                         jffs2_mark_node_obsolete(c, ref);
                         goto cont;
                 }
diff --git a/fs/jffs2/scan.c b/fs/jffs2/scan.c
index 7a46a436edfc..858e3ed8e23d 100644
--- a/fs/jffs2/scan.c
+++ b/fs/jffs2/scan.c
@@ -741,18 +741,8 @@ scan_more:
                         ofs += 4;
                         continue;
                 }
-                /* Due to poor choice of crc32 seed, an all-zero node will have a correct CRC */
-                if (!je32_to_cpu(node->hdr_crc) && !je16_to_cpu(node->nodetype) &&
-                    !je16_to_cpu(node->magic) && !je32_to_cpu(node->totlen)) {
-                        noisy_printk(&noise, "jffs2_scan_eraseblock(): All zero node header at 0x%08x.\n", ofs);
-                        if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
-                                return err;
-                        ofs += 4;
-                        continue;
-                }
 
-                if (ofs + je32_to_cpu(node->totlen) >
-                    jeb->offset + c->sector_size) {
+                if (ofs + je32_to_cpu(node->totlen) > jeb->offset + c->sector_size) {
                         /* Eep. Node goes over the end of the erase block. */
                         printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n",
                                ofs, je32_to_cpu(node->totlen));