Re: [libvirt] [PATCH 1/2] virsh vol-upload/download disallow negative offset

On 07/17/14 01:35, John Ferlan wrote: > https://bugzilla.redhat.com/show_bug.cgi?id=1087104 > > Commit id 'c6212539' explicitly allowed a negative value to be used for > offset and length as a shorthand for the largest value after commit id > 'f18c02ec' modified virStrToLong_ui() to essentially disallow a negative > value. > > However, allowing a negative value for offset ONLY worked if the negative > value was -1 since the eventual lseek() does allow a -1 to mean the end > of the file. Providing other negative values resulted in errors such as:

> > $ virsh vol-download --pool default qcow3-vol2 /home/vm-images/raw \ > --offset -2 --length -1000 > error: cannot download from volume qcow3-vol2 > error: Unable to seek /home/vm-images/qcow3-vol2 to 18446744073709551614: Invalid argument > > $ > > Thus, it seems unreasonable to expect or allow a negative value for offset > since the only benefit is to lseek() to the end of the file and then only > take advantage of how the OS would handle such a seek. For the purposes of > upload or download of volume data, that seems to be a no-op. Therefore, > disallow a negative value for offset. > > Additionally, modify the man page for vol-upload and vol-download to provide > more details regarding the valid values for both offset and length. > > Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; > --- > tools/virsh-volume.c | 6 +++--- > tools/virsh.pod | 10 ++++++++-- > 2 files changed, 11 insertions(+), 5 deletions(-) > ACK, although I'd prefer Eric stating his opinion on this too.