On 05.05.2014 11:36, Kevin Wolf wrote:
Am 04.05.2014 um 05:31 hat Max Reitz geschrieben:
If the very first allocation has a length of 0, the free_cluster_index
is still 0 after the for loop, which means that subtracting one from it
will underflow and signal an invalid range of clusters by returning
-EFBIG. However, there is no such range, as its length is 0.
Fix this by preventing underflows on free_cluster_index during the
check.
Signed-off-by: Max Reitz <mre...@redhat.com>
Heh, I wondered about this when I reviewed that other patch, and came to
the conclusion that it probably doesn't happen. Did you find a case
where it does happen in fact?
Yes, deleting the last internal snapshot results in a 0-byte allocation
for the new (empty) snapshot table. If this is the first allocation
after an image has been opened (which is the case for qemu-img snapshot
-d), you'll receive the “File too big” error message (which confused me
quite a bit at first, as I wasn't specifically testing this series).
Max
Anyway, this can't hurt:
Reviewed-by: Kevin Wolf <kw...@redhat.com>
