Set errno to zero before invoking SSL_read or SSL_write. It appears that

at least in some Windows versions, these functions are capable of returning
a failure indication without setting errno.  That puts us into an infinite
loop if the previous value happened to be EINTR.  Per report from Brendan
Hill.

Back-patch to 8.2.  We could take it further back, but since this is only
known to be an issue on Windows and we don't support Windows before 8.2,
it does not seem worth the trouble.

diff --git a/src/backend/libpq/be-secure.c b/src/backend/libpq/be-secure.c
index 3e4756f1c7c2e27847ca2e732efddd4132d4f6be..e740ae6f877f986551b20184c8e567c5a201eb7f 100644 (file)
--- a/src/backend/libpq/be-secure.c
+++ b/src/backend/libpq/be-secure.c
@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/libpq/be-secure.c,v 1.93 2009/12/09 06:37:06 mha Exp $
+ *       $PostgreSQL: pgsql/src/backend/libpq/be-secure.c,v 1.94 2009/12/30 03:45:46 tgl Exp $
  *
  *       Since the server static private key ($DataDir/server.key)
  *       will normally be stored unencrypted so that the database
@@ -245,6 +245,7 @@ secure_read(Port *port, void *ptr, size_t len)
                int                     err;
 
 rloop:
+               errno = 0;
                n = SSL_read(port->ssl, ptr, len);
                err = SSL_get_error(port->ssl, n);
                switch (err)
@@ -339,6 +340,7 @@ secure_write(Port *port, void *ptr, size_t len)
                }
 
 wloop:
+               errno = 0;
                n = SSL_write(port->ssl, ptr, len);
                err = SSL_get_error(port->ssl, n);
                switch (err)

diff --git a/src/interfaces/libpq/fe-secure.c b/src/interfaces/libpq/fe-secure.c
index 6f6052b2b05d378cbb0d7f5df1f77a04dd8f5e9a..f58be75f8a2da0eebd01fa92320f872dba8af194 100644 (file)
--- a/src/interfaces/libpq/fe-secure.c
+++ b/src/interfaces/libpq/fe-secure.c
@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/interfaces/libpq/fe-secure.c,v 1.129 2009/12/09 06:37:06 mha Exp $
+ *       $PostgreSQL: pgsql/src/interfaces/libpq/fe-secure.c,v 1.130 2009/12/30 03:45:46 tgl Exp $
  *
  * NOTES
  *
@@ -324,6 +324,7 @@ pqsecure_read(PGconn *conn, void *ptr, size_t len)
                DISABLE_SIGPIPE(conn, spinfo, return -1);
 
 rloop:
+               SOCK_ERRNO_SET(0);
                n = SSL_read(conn->ssl, ptr, len);
                err = SSL_get_error(conn->ssl, n);
                switch (err)
@@ -409,6 +410,7 @@ pqsecure_write(PGconn *conn, const void *ptr, size_t len)
 
                DISABLE_SIGPIPE(conn, spinfo, return -1);
 
+               SOCK_ERRNO_SET(0);
                n = SSL_write(conn->ssl, ptr, len);
                err = SSL_get_error(conn->ssl, n);
                switch (err)