[JFFS2] Better fix for all-zero node headers
Joakim Tjernlund [Sat, 10 Mar 2007 16:08:44 +0000 (17:08 +0100)]
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>

fs/jffs2/readinode.c
fs/jffs2/scan.c

index 49d4b0a..b09fa23 100644 (file)
@@ -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;
                }
index 7a46a43..858e3ed 100644 (file)
@@ -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));