The KJV seems to suggest that judgment was committed to the saints so that they became the judges:
KJV Daniel 7:22 Until the Ancient of days came, and judgment was given to the saints of the most High; and the time came that the saints possessed the kingdom.
However, it appears that most other English translation see it as a "ruling in the favor of" the saints:
New International Version until the Ancient of Days came and pronounced judgment in favor of the holy people of the Most High, and the time came when they possessed the kingdom.
New Living Translation until the Ancient One--the Most High--came and judged in favor of his holy people. Then the time arrived for the holy people to take over the kingdom.
English Standard Version until the Ancient of Days came, and judgment was given for the saints of the Most High, and the time came when the saints possessed the kingdom.
New American Standard Bible until the Ancient of Days came and judgment was passed in favor of the saints of the Highest One, and the time arrived when the saints took possession of the kingdom.
I note that even the ESV goes with the idea of "ruled in the favor of".
The Lexham English Septuagint also has "rendered":
LES This continued until the ancient of days came and rendered judgment for the saints of the most high. And the appointed time arrived and the saints possessed the kingdom.
The NET Bible notes have this to say:
50 tc In the LXX, Syriac, and Vulgate the verb is active, understanding “judgment” to be the object rather than the subject of the verb (i.e., “the Ancient of Days rendered judgment”). This presupposes a different vocalization of the verb (יְהַב [yéhav] rather than the MT יְהִב [yéhiv]).
Biblical Studies Press. (2006). The NET Bible First Edition Notes (Da 7:22). Biblical Studies Press.
Does the KJV get this one wrong?