17.01.2019 22:36, Eric Blake wrote: > We only had two callers to nbd_export_new; qemu-nbd.c always > passed a valid offset/length pair (because it already checked > the file length, to ensure that offset was in bounds), while > blockdev-nbd.c always passed 0/-1. Then nbd_export_new reduces > the size to a multiple of BDRV_SECTOR_SIZE (can only happen > when offset is not sector-aligned, since bdrv_getlength() > currently rounds up), which can result in offset being greater > than the enforced length, but that's not fatal (the server > rejects client requests that exceed the advertised length). > > However, I'm finding it easier to work with the code if we are > consistent on having both callers pass in a valid length, and > just assert that things are sane in nbd_export_new, meaning > that no negative values were passed, and that offset+size does > not exceed 63 bits (as that really is a fundamental limit to > later operations, whether we use off_t or uint64_t). > > Signed-off-by: Eric Blake <ebl...@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> -- Best regards, Vladimir
