Changeset 552efe3 in mainline

Timestamp:

2012-02-24T22:52:50Z (12 years ago)

Author:

Maurizio Lombardi <m.lombardi85@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

3467821

Parents:

89a0a827

Message:

mkexfat: Fix memory access bug in the upcase_table_write() function.

File:

• uspace/app/mkexfat/mkexfat.c (modified) (3 diffs)

uspace/app/mkexfat/mkexfat.c

@@ -77 +77 @@
 /** Index of the first free cluster on the device */
 #define FIRST_FREE_CLUSTER   2
+
+#define min(x, y) ((x) < (y) ? (x) : (y))
 
 typedef struct exfat_cfg {
@@ -474 +476 @@
 upcase_table_write(service_id_t service_id, exfat_cfg_t *cfg)
 {
-        int rc;
+        int rc = EOK;
         aoff64_t start_sec, nsecs, i;
         uint8_t *table_ptr;
+        uint8_t *buf;
+        size_t table_size = sizeof(upcase_table);
+
+        buf = malloc(cfg->sector_size);
+        if (!buf)
+                return ENOENT;
 
         start_sec = cfg->data_start_sector;
-        start_sec += (cfg->upcase_table_cluster * cfg->cluster_size) /
+        start_sec += ((cfg->upcase_table_cluster - 2) * cfg->cluster_size) /
             cfg->sector_size;
 
@@ -485 +493 @@
         table_ptr = (uint8_t *) upcase_table;
 
-        for (i = 0; i < nsecs; ++i, table_ptr += cfg->sector_size) {
+        for (i = 0; i < nsecs; ++i,
+            table_ptr += min(table_size, cfg->sector_size),
+            table_size -= cfg->sector_size) {
+
+                if (table_size < cfg->sector_size)
+                        memset(buf, 0, cfg->sector_size);
+                memcpy(buf, table_ptr, min(table_size, cfg->sector_size));
+
                 rc = block_write_direct(service_id,
-                    start_sec + i, 1, table_ptr);
+                    start_sec + i, 1, buf);
                 if (rc != EOK)
-                        return rc;
-        }
-
-        return EOK;
+                        break;
+        }
+
+        free(buf);
+        return rc;
 }