Fix memory leak in pg_restore with zstd-compressed data.

tglsfdc · tglsfdc · commit 3f06324705ae · 2024-12-17T22:31:26.000-05:00
EndCompressorZstd() neglected to free everything. This was most visible with a lot of large objects in the dump. Per report from Tomasz Szypowski. Back-patch to v16 where this code came in. Discussion: https://postgr.es/m/DU0PR04MB94193D038A128EF989F922D199042@DU0PR04MB9419.eurprd04.prod.outlook.com
diff --git a/src/bin/pg_dump/compress_zstd.c b/src/bin/pg_dump/compress_zstd.c
@@ -137,9 +137,10 @@ EndCompressorZstd(ArchiveHandle *AH, CompressorState *cs)
 		Assert(zstdcs->dstream == NULL);
 		_ZstdWriteCommon(AH, cs, true);
 		ZSTD_freeCStream(zstdcs->cstream);
-		pg_free(zstdcs->output.dst);
 	}
 
+	/* output buffer may be allocated in either mode */
+	pg_free(zstdcs->output.dst);
 	pg_free(zstdcs);
 }
 

Original file line number	Diff line number	Diff line change
`@@ -137,9 +137,10 @@ EndCompressorZstd(ArchiveHandle AH, CompressorState cs)`
`137`	`137`	`Assert(zstdcs->dstream == NULL);`
`138`	`138`	`_ZstdWriteCommon(AH, cs, true);`
`139`	`139`	`ZSTD_freeCStream(zstdcs->cstream);`
`140`		`- pg_free(zstdcs->output.dst);`
`141`	`140`	`}`
`142`	`141`
	`142`	`+ /* output buffer may be allocated in either mode */`
	`143`	`+ pg_free(zstdcs->output.dst);`
`143`	`144`	`pg_free(zstdcs);`
`144`	`145`	`}`
`145`	`146`