Fix memory and file descriptor leaks in pg_receivexlog/pg_basebackup

mhagander · mhagander · commit 058a050ec769 · 2012-07-12T13:33:58.000+02:00
When the internal loop mode was added, freeing memory and closing
filedescriptors before returning became important, and a few cases
in the code missed that.

Fujii Masao
diff --git a/src/bin/pg_basebackup/receivelog.c b/src/bin/pg_basebackup/receivelog.c
@@ -38,6 +38,10 @@
 #define STREAMING_HEADER_SIZE (1+sizeof(WalDataMessageHeader))
 #define STREAMING_KEEPALIVE_SIZE (1+sizeof(PrimaryKeepaliveMessage))
 
+/* fd for currently open WAL file */
+static int		walfile = -1;
+
+
 /*
  * Open a new WAL file in the specified directory. Store the name
  * (not including the full directory) in namebuf. Assumes there is
@@ -96,6 +100,7 @@ open_walfile(XLogRecPtr startpoint, uint32 timeline, char *basedir, char *namebu
 		{
 			fprintf(stderr, _("%s: could not pad WAL segment %s: %s\n"),
 					progname, fn, strerror(errno));
+			free(zerobuf);
 			close(f);
 			unlink(fn);
 			return -1;
@@ -120,7 +125,7 @@ open_walfile(XLogRecPtr startpoint, uint32 timeline, char *basedir, char *namebu
  * completed writing the whole segment.
  */
 static bool
-close_walfile(int walfile, char *basedir, char *walname, bool segment_complete)
+close_walfile(char *basedir, char *walname, bool segment_complete)
 {
 	off_t		currpos = lseek(walfile, 0, SEEK_CUR);
 
@@ -142,8 +147,10 @@ close_walfile(int walfile, char *basedir, char *walname, bool segment_complete)
 	{
 		fprintf(stderr, _("%s: could not close file %s: %s\n"),
 				progname, walname, strerror(errno));
+		walfile = -1;
 		return false;
 	}
+	walfile = -1;
 
 	/*
 	 * Rename the .partial file only if we've completed writing the whole
@@ -270,7 +277,6 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 	char		current_walfile_name[MAXPGPATH];
 	PGresult   *res;
 	char	   *copybuf = NULL;
-	int			walfile = -1;
 	int64		last_status = -1;
 	XLogRecPtr	blockpos = InvalidXLogRecPtr;
 
@@ -315,6 +321,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 	{
 		fprintf(stderr, _("%s: could not start replication: %s\n"),
 				progname, PQresultErrorMessage(res));
+		PQclear(res);
 		return false;
 	}
 	PQclear(res);
@@ -341,9 +348,9 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 		 */
 		if (stream_stop && stream_stop(blockpos, timeline, false))
 		{
-			if (walfile != -1)
+			if (walfile != -1 && !close_walfile(basedir, current_walfile_name, rename_partial))
 				/* Potential error message is written by close_walfile */
-				return close_walfile(walfile, basedir, current_walfile_name, rename_partial);
+				goto error;
 			return true;
 		}
 
@@ -370,7 +377,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 			{
 				fprintf(stderr, _("%s: could not send feedback packet: %s"),
 						progname, PQerrorMessage(conn));
-				return false;
+				goto error;
 			}
 
 			last_status = now;
@@ -421,14 +428,14 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 			{
 				fprintf(stderr, _("%s: select() failed: %s\n"),
 						progname, strerror(errno));
-				return false;
+				goto error;
 			}
 			/* Else there is actually data on the socket */
 			if (PQconsumeInput(conn) == 0)
 			{
 				fprintf(stderr, _("%s: could not receive data from WAL stream: %s\n"),
 						progname, PQerrorMessage(conn));
-				return false;
+				goto error;
 			}
 			continue;
 		}
@@ -439,7 +446,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 		{
 			fprintf(stderr, _("%s: could not read copy data: %s\n"),
 					progname, PQerrorMessage(conn));
-			return false;
+			goto error;
 		}
 		if (copybuf[0] == 'k')
 		{
@@ -451,21 +458,21 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 			{
 				fprintf(stderr, _("%s: keepalive message is incorrect size: %d\n"),
 						progname, r);
-				return false;
+				goto error;
 			}
 			continue;
 		}
 		else if (copybuf[0] != 'w')
 		{
 			fprintf(stderr, _("%s: unrecognized streaming header: \"%c\"\n"),
 					progname, copybuf[0]);
-			return false;
+			goto error;
 		}
 		if (r < STREAMING_HEADER_SIZE + 1)
 		{
 			fprintf(stderr, _("%s: streaming header too small: %d\n"),
 					progname, r);
-			return false;
+			goto error;
 		}
 
 		/* Extract WAL location for this block */
@@ -483,7 +490,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 			{
 				fprintf(stderr, _("%s: received xlog record for offset %u with no file open\n"),
 						progname, xlogoff);
-				return false;
+				goto error;
 			}
 		}
 		else
@@ -494,7 +501,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 			{
 				fprintf(stderr, _("%s: got WAL data offset %08x, expected %08x\n"),
 						progname, xlogoff, (int) lseek(walfile, 0, SEEK_CUR));
-				return false;
+				goto error;
 			}
 		}
 
@@ -520,7 +527,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 									   basedir, current_walfile_name);
 				if (walfile == -1)
 					/* Error logged by open_walfile */
-					return false;
+					goto error;
 			}
 
 			if (write(walfile,
@@ -532,7 +539,7 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 						bytes_to_write,
 						current_walfile_name,
 						strerror(errno));
-				return false;
+				goto error;
 			}
 
 			/* Write was successful, advance our position */
@@ -544,11 +551,10 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 			/* Did we reach the end of a WAL segment? */
 			if (blockpos % XLOG_SEG_SIZE == 0)
 			{
-				if (!close_walfile(walfile, basedir, current_walfile_name, false))
+				if (!close_walfile(basedir, current_walfile_name, false))
 					/* Error message written in close_walfile() */
-					return false;
+					goto error;
 
-				walfile = -1;
 				xlogoff = 0;
 
 				if (stream_stop != NULL)
@@ -577,8 +583,22 @@ ReceiveXlogStream(PGconn *conn, XLogRecPtr startpos, uint32 timeline, char *sysi
 	{
 		fprintf(stderr, _("%s: unexpected termination of replication stream: %s\n"),
 				progname, PQresultErrorMessage(res));
-		return false;
+		goto error;
 	}
 	PQclear(res);
+
+	if (copybuf != NULL)
+		PQfreemem(copybuf);
+	if (walfile != -1 && close(walfile) != 0)
+		fprintf(stderr, _("%s: could not close file %s: %s\n"),
+				progname, current_walfile_name, strerror(errno));
 	return true;
+
+error:
+	if (copybuf != NULL)
+		PQfreemem(copybuf);
+	if (walfile != -1 && close(walfile) != 0)
+		fprintf(stderr, _("%s: could not close file %s: %s\n"),
+				progname, current_walfile_name, strerror(errno));
+	return false;
 }
diff --git a/src/bin/pg_basebackup/streamutil.c b/src/bin/pg_basebackup/streamutil.c
@@ -143,6 +143,17 @@ GetConnection(void)
 
 		tmpconn = PQconnectdbParams(keywords, values, true);
 
+		/*
+		 * If there is too little memory even to allocate the PGconn object
+		 * and PQconnectdbParams returns NULL, we call exit(1) directly.
+		 */
+		if (!tmpconn)
+		{
+			fprintf(stderr, _("%s: could not connect to server\n"),
+					progname);
+			exit(1);
+		}
+
 		if (PQstatus(tmpconn) == CONNECTION_BAD &&
 			PQconnectionNeedsPassword(tmpconn) &&
 			dbgetpassword != -1)
@@ -154,8 +165,11 @@ GetConnection(void)
 
 		if (PQstatus(tmpconn) != CONNECTION_OK)
 		{
-			fprintf(stderr, _("%s: could not connect to server: %s"),
+			fprintf(stderr, _("%s: could not connect to server: %s\n"),
 					progname, PQerrorMessage(tmpconn));
+			PQfinish(tmpconn);
+			free(values);
+			free(keywords);
 			return NULL;
 		}
 

Original file line number	Diff line number	Diff line change
`@@ -38,6 +38,10 @@`
`38`	`38`	`#define STREAMING_HEADER_SIZE (1+sizeof(WalDataMessageHeader))`
`39`	`39`	`#define STREAMING_KEEPALIVE_SIZE (1+sizeof(PrimaryKeepaliveMessage))`
`40`	`40`
	`41`	`+/* fd for currently open WAL file */`
	`42`	`+static int walfile = -1;`
	`43`	`+`
	`44`	`+`
`41`	`45`	`/*`
`42`	`46`	`* Open a new WAL file in the specified directory. Store the name`
`43`	`47`	`* (not including the full directory) in namebuf. Assumes there is`
`@@ -96,6 +100,7 @@ open_walfile(XLogRecPtr startpoint, uint32 timeline, char basedir, char namebu`
`96`	`100`	`{`
`97`	`101`	`fprintf(stderr, _("%s: could not pad WAL segment %s: %s\n"),`
`98`	`102`	`progname, fn, strerror(errno));`
	`103`	`+ free(zerobuf);`
`99`	`104`	`close(f);`
`100`	`105`	`unlink(fn);`
`101`	`106`	`return -1;`
`@@ -120,7 +125,7 @@ open_walfile(XLogRecPtr startpoint, uint32 timeline, char basedir, char namebu`
`120`	`125`	`* completed writing the whole segment.`
`121`	`126`	`*/`
`122`	`127`	`static bool`
`123`		`-close_walfile(int walfile, char basedir, char walname, bool segment_complete)`
	`128`	`+close_walfile(char basedir, char walname, bool segment_complete)`
`124`	`129`	`{`
`125`	`130`	`off_t currpos = lseek(walfile, 0, SEEK_CUR);`
`126`	`131`
`@@ -142,8 +147,10 @@ close_walfile(int walfile, char basedir, char walname, bool segment_complete)`
`142`	`147`	`{`
`143`	`148`	`fprintf(stderr, _("%s: could not close file %s: %s\n"),`
`144`	`149`	`progname, walname, strerror(errno));`
	`150`	`+ walfile = -1;`
`145`	`151`	`return false;`
`146`	`152`	`}`
	`153`	`+ walfile = -1;`
`147`	`154`
`148`	`155`	`/*`
`149`	`156`	`* Rename the .partial file only if we've completed writing the whole`
`@@ -270,7 +277,6 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`270`	`277`	`char current_walfile_name[MAXPGPATH];`
`271`	`278`	`PGresult *res;`
`272`	`279`	`char *copybuf = NULL;`
`273`		`- int walfile = -1;`
`274`	`280`	`int64 last_status = -1;`
`275`	`281`	`XLogRecPtr blockpos = InvalidXLogRecPtr;`
`276`	`282`
`@@ -315,6 +321,7 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`315`	`321`	`{`
`316`	`322`	`fprintf(stderr, _("%s: could not start replication: %s\n"),`
`317`	`323`	`progname, PQresultErrorMessage(res));`
	`324`	`+ PQclear(res);`
`318`	`325`	`return false;`
`319`	`326`	`}`
`320`	`327`	`PQclear(res);`
`@@ -341,9 +348,9 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`341`	`348`	`*/`
`342`	`349`	`if (stream_stop && stream_stop(blockpos, timeline, false))`
`343`	`350`	`{`
`344`		`- if (walfile != -1)`
	`351`	`+ if (walfile != -1 && !close_walfile(basedir, current_walfile_name, rename_partial))`
`345`	`352`	`/* Potential error message is written by close_walfile */`
`346`		`- return close_walfile(walfile, basedir, current_walfile_name, rename_partial);`
	`353`	`+ goto error;`
`347`	`354`	`return true;`
`348`	`355`	`}`
`349`	`356`
`@@ -370,7 +377,7 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`370`	`377`	`{`
`371`	`378`	`fprintf(stderr, _("%s: could not send feedback packet: %s"),`
`372`	`379`	`progname, PQerrorMessage(conn));`
`373`		`- return false;`
	`380`	`+ goto error;`
`374`	`381`	`}`
`375`	`382`
`376`	`383`	`last_status = now;`
`@@ -421,14 +428,14 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`421`	`428`	`{`
`422`	`429`	`fprintf(stderr, _("%s: select() failed: %s\n"),`
`423`	`430`	`progname, strerror(errno));`
`424`		`- return false;`
	`431`	`+ goto error;`
`425`	`432`	`}`
`426`	`433`	`/* Else there is actually data on the socket */`
`427`	`434`	`if (PQconsumeInput(conn) == 0)`
`428`	`435`	`{`
`429`	`436`	`fprintf(stderr, _("%s: could not receive data from WAL stream: %s\n"),`
`430`	`437`	`progname, PQerrorMessage(conn));`
`431`		`- return false;`
	`438`	`+ goto error;`
`432`	`439`	`}`
`433`	`440`	`continue;`
`434`	`441`	`}`
`@@ -439,7 +446,7 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`439`	`446`	`{`
`440`	`447`	`fprintf(stderr, _("%s: could not read copy data: %s\n"),`
`441`	`448`	`progname, PQerrorMessage(conn));`
`442`		`- return false;`
	`449`	`+ goto error;`
`443`	`450`	`}`
`444`	`451`	`if (copybuf[0] == 'k')`
`445`	`452`	`{`
`@@ -451,21 +458,21 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`451`	`458`	`{`
`452`	`459`	`fprintf(stderr, _("%s: keepalive message is incorrect size: %d\n"),`
`453`	`460`	`progname, r);`
`454`		`- return false;`
	`461`	`+ goto error;`
`455`	`462`	`}`
`456`	`463`	`continue;`
`457`	`464`	`}`
`458`	`465`	`else if (copybuf[0] != 'w')`
`459`	`466`	`{`
`460`	`467`	`fprintf(stderr, _("%s: unrecognized streaming header: \"%c\"\n"),`
`461`	`468`	`progname, copybuf[0]);`
`462`		`- return false;`
	`469`	`+ goto error;`
`463`	`470`	`}`
`464`	`471`	`if (r < STREAMING_HEADER_SIZE + 1)`
`465`	`472`	`{`
`466`	`473`	`fprintf(stderr, _("%s: streaming header too small: %d\n"),`
`467`	`474`	`progname, r);`
`468`		`- return false;`
	`475`	`+ goto error;`
`469`	`476`	`}`
`470`	`477`
`471`	`478`	`/* Extract WAL location for this block */`
`@@ -483,7 +490,7 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`483`	`490`	`{`
`484`	`491`	`fprintf(stderr, _("%s: received xlog record for offset %u with no file open\n"),`
`485`	`492`	`progname, xlogoff);`
`486`		`- return false;`
	`493`	`+ goto error;`
`487`	`494`	`}`
`488`	`495`	`}`
`489`	`496`	`else`
`@@ -494,7 +501,7 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`494`	`501`	`{`
`495`	`502`	`fprintf(stderr, _("%s: got WAL data offset %08x, expected %08x\n"),`
`496`	`503`	`progname, xlogoff, (int) lseek(walfile, 0, SEEK_CUR));`
`497`		`- return false;`
	`504`	`+ goto error;`
`498`	`505`	`}`
`499`	`506`	`}`
`500`	`507`
`@@ -520,7 +527,7 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`520`	`527`	`basedir, current_walfile_name);`
`521`	`528`	`if (walfile == -1)`
`522`	`529`	`/* Error logged by open_walfile */`
`523`		`- return false;`
	`530`	`+ goto error;`
`524`	`531`	`}`
`525`	`532`
`526`	`533`	`if (write(walfile,`
`@@ -532,7 +539,7 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`532`	`539`	`bytes_to_write,`
`533`	`540`	`current_walfile_name,`
`534`	`541`	`strerror(errno));`
`535`		`- return false;`
	`542`	`+ goto error;`
`536`	`543`	`}`
`537`	`544`
`538`	`545`	`/* Write was successful, advance our position */`
`@@ -544,11 +551,10 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`544`	`551`	`/* Did we reach the end of a WAL segment? */`
`545`	`552`	`if (blockpos % XLOG_SEG_SIZE == 0)`
`546`	`553`	`{`
`547`		`- if (!close_walfile(walfile, basedir, current_walfile_name, false))`
	`554`	`+ if (!close_walfile(basedir, current_walfile_name, false))`
`548`	`555`	`/* Error message written in close_walfile() */`
`549`		`- return false;`
	`556`	`+ goto error;`
`550`	`557`
`551`		`- walfile = -1;`
`552`	`558`	`xlogoff = 0;`
`553`	`559`
`554`	`560`	`if (stream_stop != NULL)`
`@@ -577,8 +583,22 @@ ReceiveXlogStream(PGconn conn, XLogRecPtr startpos, uint32 timeline, char sysi`
`577`	`583`	`{`
`578`	`584`	`fprintf(stderr, _("%s: unexpected termination of replication stream: %s\n"),`
`579`	`585`	`progname, PQresultErrorMessage(res));`
`580`		`- return false;`
	`586`	`+ goto error;`
`581`	`587`	`}`
`582`	`588`	`PQclear(res);`
	`589`	`+`
	`590`	`+ if (copybuf != NULL)`
	`591`	`+ PQfreemem(copybuf);`
	`592`	`+ if (walfile != -1 && close(walfile) != 0)`
	`593`	`+ fprintf(stderr, _("%s: could not close file %s: %s\n"),`
	`594`	`+ progname, current_walfile_name, strerror(errno));`
`583`	`595`	`return true;`
	`596`	`+`
	`597`	`+error:`
	`598`	`+ if (copybuf != NULL)`
	`599`	`+ PQfreemem(copybuf);`
	`600`	`+ if (walfile != -1 && close(walfile) != 0)`
	`601`	`+ fprintf(stderr, _("%s: could not close file %s: %s\n"),`
	`602`	`+ progname, current_walfile_name, strerror(errno));`
	`603`	`+ return false;`
`584`	`604`	`}`