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authorHaavard Skinnemoen <haavard.skinnemoen@atmel.com>2009-03-27 16:14:38 +0100
committerHaavard Skinnemoen <haavard.skinnemoen@atmel.com>2009-03-27 16:14:38 +0100
commitb92efa9abffc4a634cd2e7a0f81f8aa6310d67c9 (patch)
tree9847508d9b8d4e585f90db4a453bfbc3700c997e /fs/ubifs/io.c
parenta16fffdd8eb95ebab7dc22414896fe6493951e0e (diff)
parentbe0ea69674ed95e1e98cb3687a241badc756d228 (diff)
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into avr32-arch
Diffstat (limited to 'fs/ubifs/io.c')
-rw-r--r--fs/ubifs/io.c22
1 files changed, 14 insertions, 8 deletions
diff --git a/fs/ubifs/io.c b/fs/ubifs/io.c
index 01682713af6..e8e632a1dcd 100644
--- a/fs/ubifs/io.c
+++ b/fs/ubifs/io.c
@@ -29,7 +29,7 @@
* would have been wasted for padding to the nearest minimal I/O unit boundary.
* Instead, data first goes to the write-buffer and is flushed when the
* buffer is full or when it is not used for some time (by timer). This is
- * similarto the mechanism is used by JFFS2.
+ * similar to the mechanism is used by JFFS2.
*
* Write-buffers are defined by 'struct ubifs_wbuf' objects and protected by
* mutexes defined inside these objects. Since sometimes upper-level code
@@ -75,7 +75,7 @@ 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
+ * @must_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
@@ -83,11 +83,17 @@ void ubifs_ro_mode(struct ubifs_info *c, int err)
* node length in the common header could cause UBIFS to read memory outside of
* allocated buffer when checking the CRC checksum.
*
- * This function returns zero in case of success %-EUCLEAN in case of bad CRC
- * or magic.
+ * This function may skip data nodes CRC checking if @c->no_chk_data_crc is
+ * true, which is controlled by corresponding UBIFS mount option. However, if
+ * @must_chk_crc is true, then @c->no_chk_data_crc is ignored and CRC is
+ * checked. Similarly, if @c->always_chk_crc is true, @c->no_chk_data_crc is
+ * ignored and CRC is checked.
+ *
+ * This function returns zero in case of success and %-EUCLEAN in case of bad
+ * CRC or magic.
*/
int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
- int offs, int quiet, int chk_crc)
+ int offs, int quiet, int must_chk_crc)
{
int err = -EINVAL, type, node_len;
uint32_t crc, node_crc, magic;
@@ -123,9 +129,9 @@ 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;
+ if (!must_chk_crc && type == UBIFS_DATA_NODE && !c->always_chk_crc &&
+ c->no_chk_data_crc)
+ return 0;
crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
node_crc = le32_to_cpu(ch->crc);