postgres.git / summary / log / commit / refs

commit    dce92e59b1a9ff8401a660a1ac448ea37d498284
Author:   Peter Eisentraut <peter@eisentraut.org>
Date:     Thu Nov 17 13:12:04 2022 +0000
First released in: 16.0

    libpq: Correct processing of startup response messages
    
    After sending a startup message, libpq expects either an error
    response ('E') or an authentication request ('R').  Before processing
    the message, it ensures it has read enough bytes to correspond to the
    length specified in the message.  However, when processing the 'R'
    message, if an EOF status is returned it loops back waiting for more
    input, even though we already checked that we have enough input.  In
    this particular case, this is probably not reachable anyway, because
    other code ensures we have enough bytes for an authentication request
    message, but the code is wrong and misleading.  In the more general
    case, processing a faulty message could result in an EOF status, which
    would then result in an infinite loop waiting for the end of a message
    that will never come.  The correction is to make this an error.
    
    Reported-by: Jacob Champion <jchampion@timescale.com>
    Discussion: https://www.postgresql.org/message-id/flat/f9c7862f-b864-8ef7-a861-c4638c83e209@enterprisedb.com


 src/interfaces/libpq/fe-connect.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index a6120bf58b8..7d54aa35899 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -3358,8 +3358,7 @@ keep_going:						/* We will come back to here until there is
 				/* Get the type of request. */
 				if (pqGetInt((int *) &areq, 4, conn))
 				{
-					/* We'll come back when there are more data */
-					return PGRES_POLLING_READING;
+					goto error_return;
 				}
 				msgLength -= 4;
 


[parent: 3d0c95bc8920]