diff options
Diffstat (limited to 'fs/ubifs')
| -rw-r--r-- | fs/ubifs/io.c | 22 | ||||
| -rw-r--r-- | fs/ubifs/tnc.c | 12 | ||||
| -rw-r--r-- | fs/ubifs/ubifs.h | 2 |
3 files changed, 23 insertions, 13 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); diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c index f7e36f54552..fa28a84c6a1 100644 --- a/fs/ubifs/tnc.c +++ b/fs/ubifs/tnc.c @@ -443,6 +443,11 @@ static int tnc_read_node_nm(struct ubifs_info *c, struct ubifs_zbranch *zbr, * This function performs that same function as ubifs_read_node except that * it does not require that there is actually a node present and instead * the return code indicates if a node was read. + * + * Note, this function does not check CRC of data nodes if @c->no_chk_data_crc + * is true (it is controlled by corresponding mount option). However, if + * @c->always_chk_crc is true, @c->no_chk_data_crc is ignored and CRC is always + * checked. */ static int try_read_node(const struct ubifs_info *c, void *buf, int type, int len, int lnum, int offs) @@ -470,9 +475,8 @@ static int try_read_node(const struct ubifs_info *c, void *buf, int type, if (node_len != len) return 0; - if (type == UBIFS_DATA_NODE && !c->always_chk_crc) - if (c->no_chk_data_crc) - return 0; + if (type == UBIFS_DATA_NODE && !c->always_chk_crc && c->no_chk_data_crc) + return 1; crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8); node_crc = le32_to_cpu(ch->crc); @@ -1506,7 +1510,7 @@ out: * * Note, if the bulk-read buffer length (@bu->buf_len) is known, this function * makes sure bulk-read nodes fit the buffer. Otherwise, this function prepares - * maxumum possible amount of nodes for bulk-read. + * maximum possible amount of nodes for bulk-read. */ int ubifs_tnc_get_bu_keys(struct ubifs_info *c, struct bu_info *bu) { diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h index 9999ff0aaa4..29dfa816077 100644 --- a/fs/ubifs/ubifs.h +++ b/fs/ubifs/ubifs.h @@ -1428,7 +1428,7 @@ int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len, int ubifs_write_node(struct ubifs_info *c, void *node, int len, int lnum, int offs, int dtype); 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); void ubifs_prepare_node(struct ubifs_info *c, void *buf, int len, int pad); void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last); int ubifs_io_init(struct ubifs_info *c); |