The major problem for Soviet bloc leaders posed by the spiraling dissent of recent months is finding ways to bring critics into the line without creating the sort of confrontation that in the past has ended in bloodshed, the use of Soviet troops and added strains with the West.

Repeated pledges by the Communist governments that they will adhere to all provisions of the 1975 Helsinki declaration on European security, including those on human rights, has inspired people throughout the region to test those rights and has set a standard by which official reactions may be judged.

In Czechoslovakia, East Germany and the Soviet Union, authorities are imposing a selective form of repression against those who have spoken out for respect of law and personal freedom. A few critics have been arrested or exiled. Many others have been harassed by administrative or police means. Yet the governments have all stopped short thus far of a comprehensive crackdown on every competition singer and political activist.

The Kremlin's aim, reflected by its allies, seems to be to contain the spread of dissent - and, especially in East Germany and the Soviet Union, the urge to emigrate - by making the hazards great enough to dissuade most people from taking the risks. Thus isolated and exhausted, the remaining dissidents can be sent abroad or silenced at home.

In poland, the situation is perhaps the most complicated. The workers' riots in June against food price increases and the outspoken attacks by the powerful Catholic Church present a far more formidable challenge to the leadership than do attacks by intellectuals there and elsewhere.

Polish authoities have moved with extreme caution, seeking to appease the population with economic concessions and avoiding any open clash with the church. While intellectual critics organized in defense of workers' interests have been assailed, no serious punitive action has been taken against them.

Less is known about what is happening in Hungary, considered the bloc's most relaxed government> as well as Romania and Bulgaria, which are among the toughest. But there are signs of activity: 20 to 30 Hungarian intellectuals last month signed a letter in support of the "Charter 77" human rights manifesto that so angered the Czechoslovak government. A talented young Romanian writer was recently sent to the West and warned not to return home after one of his manuscripts was published in France.

Probably the main reason the Soviet bloc leaders are so anxious to move quickly in defusing dissent is next summer's Belgrade conference, where complaince with the Helsinki declaration will be reviewed by the 35 signatories, including the United States.

For months, the East has been building a presentation intended to show that it has done more than Western countries on concrete matters such as easing visa restrictions for foreigners. Those asdsertions will sound distinctly hollow if human rights advocates are crushed in the meantime or, on the other hand, are especially vocal at the time of the conference - hence the need to silence critics but without using means so brutal that further troble results.

Of greater importance but perhaps less immediate concern for the Kremlin and its allies is the effect their actions could have on relations with a Carter administration that has said its commitment to human rights will be "absolute."

Moscow has already criticized the State Department's warning against intimidation of Andrei Sakharov, the Nobel peace-prize-winning dissident - a warning that President Carter later said he had not authorized, although it "reflected" his sentiments.

But many diplomats feel that Helsinki, plus Carte's commitment to human rights, can help to breathe more freedom into Eastern Europe.

In the Kissinger era, the U.S. policy toward Eastern Europe was to maintain peace and stability, not to stir things up, because Eastern Europe was a volatile place that had to live under Soviet domination.

This was part of the so-called Sonenfeld doctine. "Yet you can't go from that doctrine and fears fo an explosion in Eastern Europe to just ignoring the struggle for freedom in these countries now," one U.S. diplomat said. "That's incompatible with American traditions."

Also, the powerful Western Communist parties have made repression in the Soviet bloc a key point of contention.

Moscow appears to be giving its allies considerable leeways in handling their problems, but the Czechoslovak charter has elicited sharp Soviet response. The document, said the government newspaper Izvestia, contains "false and crude slander against Czechoslovakia, its achievements adn political system and its workers." By comparison, almost nothing has been said about dissent in Poland and East Germany.

While no formal links exist between dissidents of the various countries, solidarity clearly does, as expressed last week by Sakharov.

Speaking only hours after he had been officially advised that he faces criminal charges unless he ceases his activities, Sakharov observed that his efforts and those of other human-rights advocates in the Soviet Union "are part of a struggle that seems especially important at this moment when in Czechoslovakia, Poland and other countries of Eastern Europe, the movement is moving to a new level.

This is how political dissent is being waged and how the authorities are respondin in the Soviet Union and three of its major Eastern European allies: