diff options
Diffstat (limited to 'fs/ubifs/io.c')
| -rw-r--r-- | fs/ubifs/io.c | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/fs/ubifs/io.c b/fs/ubifs/io.c index 3374f91b6709..01682713af69 100644 --- a/fs/ubifs/io.c +++ b/fs/ubifs/io.c @@ -54,12 +54,28 @@ #include "ubifs.h" /** + * ubifs_ro_mode - switch UBIFS to read read-only mode. + * @c: UBIFS file-system description object + * @err: error code which is the reason of switching to R/O mode + */ +void ubifs_ro_mode(struct ubifs_info *c, int err) +{ + if (!c->ro_media) { + c->ro_media = 1; + c->no_chk_data_crc = 0; + ubifs_warn("switched to read-only mode, error %d", err); + dbg_dump_stack(); + } +} + +/** * ubifs_check_node - check node. * @c: UBIFS file-system description object * @buf: node to check * @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 @@ -71,7 +87,7 @@ * 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; @@ -107,6 +123,10 @@ 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) { @@ -708,7 +728,7 @@ 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; @@ -767,7 +787,7 @@ 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; |