fs/squashfs: sqfs_read: remove buggy offset functionality
offset is the offset in the file read, not the offset in the destination
buffer.
If the offset is not null, this will lead to a memory corruption.
So, for now, we are returning an error if the offset is used.
Signed-off-by: Richard Genoud <richard.genoud@posteo.net>
diff --git a/fs/squashfs/sqfs.c b/fs/squashfs/sqfs.c
index 1ecdd01..80a85e7 100644
--- a/fs/squashfs/sqfs.c
+++ b/fs/squashfs/sqfs.c
@@ -1326,6 +1326,14 @@
*actread = 0;
+ if (offset) {
+ /*
+ * TODO: implement reading at an offset in file
+ */
+ printf("Error: reading at a specific offset in a squashfs file is not supported yet.\n");
+ return -EINVAL;
+ }
+
/*
* sqfs_opendir will uncompress inode and directory tables, and will
* return a pointer to the directory that contains the requested file.
@@ -1465,12 +1473,12 @@
if ((*actread + dest_len) > len)
dest_len = len - *actread;
- memcpy(buf + offset + *actread, datablock, dest_len);
+ memcpy(buf + *actread, datablock, dest_len);
*actread += dest_len;
} else {
if ((*actread + table_size) > len)
table_size = len - *actread;
- memcpy(buf + offset + *actread, data, table_size);
+ memcpy(buf + *actread, data, table_size);
*actread += table_size;
}
@@ -1522,7 +1530,7 @@
goto out;
}
- for (j = offset + *actread; j < finfo.size; j++) {
+ for (j = *actread; j < finfo.size; j++) {
memcpy(buf + j, &fragment_block[finfo.offset + j], 1);
(*actread)++;
}
@@ -1532,7 +1540,7 @@
} else if (finfo.frag && !finfo.comp) {
fragment_block = (void *)fragment + table_offset;
- for (j = offset + *actread; j < finfo.size; j++) {
+ for (j = *actread; j < finfo.size; j++) {
memcpy(buf + j, &fragment_block[finfo.offset + j], 1);
(*actread)++;
}