0001-Respect-return-type-of-LZ4File_read_internal.patch

From 79860a9600f4e677f10be39db507f38c711812cf Mon Sep 17 00:00:00 2001
From: Tomas Vondra <tomas@2ndquadrant.com>
Date: Mon, 13 Mar 2023 20:39:37 +0100
Subject: [PATCH 1/4] Respect return type of LZ4File_read_internal

The function LZ4File_gets() was storing the return value of
LZ4File_read_internal in a variable of the wrong type, disregarding sign-es.
As a consequence, LZ4File_gets() would not take the error path when it should.

In an attempt to improve readability, spell out the significance of a negative
return value of LZ4File_read_internal() in LZ4File_read().

Reported-by: Alexander Lakhin <exclusion@gmail.com>
---
 src/bin/pg_dump/compress_lz4.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/bin/pg_dump/compress_lz4.c b/src/bin/pg_dump/compress_lz4.c
index 63e794cdc6..cc039f0b47 100644
--- a/src/bin/pg_dump/compress_lz4.c
+++ b/src/bin/pg_dump/compress_lz4.c
@@ -453,7 +453,7 @@ LZ4File_read(void *ptr, size_t size, CompressFileHandle *CFH)
 	int			ret;
 
 	ret = LZ4File_read_internal(fs, ptr, size, false);
-	if (ret != size && !LZ4File_eof(CFH))
+	if (ret < 0 || (ret != size && !LZ4File_eof(CFH)))
 		pg_fatal("could not read from input file: %s", LZ4File_get_error(CFH));
 
 	return ret;
@@ -486,14 +486,14 @@ static char *
 LZ4File_gets(char *ptr, int size, CompressFileHandle *CFH)
 {
 	LZ4File    *fs = (LZ4File *) CFH->private_data;
-	size_t		dsize;
+	int			ret;
 
-	dsize = LZ4File_read_internal(fs, ptr, size, true);
-	if (dsize < 0)
+	ret = LZ4File_read_internal(fs, ptr, size, true);
+	if (ret < 0)
 		pg_fatal("could not read from input file: %s", LZ4File_get_error(CFH));
 
 	/* Done reading */
-	if (dsize == 0)
+	if (ret == 0)
 		return NULL;
 
 	return ptr;
-- 
2.39.2