UBIFS: add no_chk_data_crc mount option

[linux-2.6-omap-h63xx.git] / fs / ubifs / io.c

diff --git a/fs/ubifs/io.c b/fs/ubifs/io.c
index 054363f2b207398ff6110fa74a7333d84d43dbc4..40e2790b62ceedea2f8075a1a6a78a2a734be0cd 100644 (file)
--- a/fs/ubifs/io.c
+++ b/fs/ubifs/io.c
@@ -74,6 +74,7 @@ void ubifs_ro_mode(struct ubifs_info *c, int err)
  * @lnum: logical eraseblock number
  * @offs: offset within the logical eraseblock
  * @quiet: print no messages
+ * @chk_crc: indicates whether to always check the CRC
  *
  * This function checks node magic number and CRC checksum. This function also
  * validates node length to prevent UBIFS from becoming crazy when an attacker
@@ -85,7 +86,7 @@ void ubifs_ro_mode(struct ubifs_info *c, int err)
  * or magic.
  */
 int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
-                    int offs, int quiet)
+                    int offs, int quiet, int chk_crc)
 {
        int err = -EINVAL, type, node_len;
        uint32_t crc, node_crc, magic;
@@ -121,6 +122,10 @@ int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
                   node_len > c->ranges[type].max_len)
                goto out_len;
 
+       if (!chk_crc && type == UBIFS_DATA_NODE && !c->always_chk_crc)
+               if (c->no_chk_data_crc)
+                       return 0;
+
        crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
        node_crc = le32_to_cpu(ch->crc);
        if (crc != node_crc) {
@@ -722,7 +727,7 @@ int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len,
                goto out;
        }
 
-       err = ubifs_check_node(c, buf, lnum, offs, 0);
+       err = ubifs_check_node(c, buf, lnum, offs, 0, 0);
        if (err) {
                ubifs_err("expected node type %d", type);
                return err;
@@ -781,7 +786,7 @@ int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len,
                goto out;
        }
 
-       err = ubifs_check_node(c, buf, lnum, offs, 0);
+       err = ubifs_check_node(c, buf, lnum, offs, 0, 0);
        if (err) {
                ubifs_err("expected node type %d", type);
                return err;