vmdk: Fix possible segfaults

Data we read from the disk isn't necessarily null terminated and may not
contain the string we're looking for. The code needs to be a bit more careful
here.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2011-10-26 12:25:52 +02:00
parent 99f1835d9b
commit 93897b9fd4

View File

@ -227,6 +227,7 @@ static uint32_t vmdk_read_cid(BlockDriverState *bs, int parent)
cid_str_size = sizeof("CID");
}
desc[DESC_SIZE - 1] = '\0';
p_name = strstr(desc, cid_str);
if (p_name != NULL) {
p_name += cid_str_size;
@ -243,13 +244,17 @@ static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid)
BDRVVmdkState *s = bs->opaque;
int ret;
memset(desc, 0, sizeof(desc));
ret = bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE);
if (ret < 0) {
return ret;
}
desc[DESC_SIZE - 1] = '\0';
tmp_str = strstr(desc, "parentCID");
if (tmp_str == NULL) {
return -EINVAL;
}
pstrcpy(tmp_desc, sizeof(tmp_desc), tmp_str);
p_name = strstr(desc, "CID");
if (p_name != NULL) {