openrsync through 0.5.0, as used in OpenBSD through 7.8 and on other platforms, allows a client to cause a server SIGSEGV by specifying a length of zero for block data, because the relationship between p->rem and p->len is not checked.Referenceshttps://github.com/kristapsdz/openrsync/issues/34https://github.com/openbsd/src/blob/60b9c3dff1abf933e85e3c4d96b54201ee947513/usr.bin/rsync/blocks.c#L480-L481
