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 <tgole...@redhat.com>
---
qemu-nbd.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/qemu-nbd.c b/qemu-nbd.c
index 99297a5..705b95e 100644
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -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) {
--
2.10.0
v1 -> v2:
- cast off_t variables to type with known formatting flag
