qemu-nbd: Shrink image size by specified offset

When --offset is set the apparent device size has to be adjusted
accordingly. Otherwise client may request read/write beyond the file end
which would fail.

Signed-off-by: Tomáš Golembiovský <tgolembi@redhat.com>
Message-Id: <8a31654cb182932db78b95aae1e904fc2bd1c465.1475698895.git.tgolembi@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Tomáš Golembiovský 2016-10-05 23:40:20 +02:00 committed by Paolo Bonzini
parent fbe7e3327a
commit e424b6550f

View file

@ -901,6 +901,14 @@ int main(int argc, char **argv)
exit(EXIT_FAILURE);
}
if (dev_offset >= fd_size) {
error_report("Offset (%lld) has to be smaller than the image size "
"(%lld)",
(long long int)dev_offset, (long long int)fd_size);
exit(EXIT_FAILURE);
}
fd_size -= dev_offset;
if (partition != -1) {
ret = find_partition(blk, partition, &dev_offset, &fd_size);
if (ret < 0) {