Fix off_t overflow in pg_basebackup on Windows.

macdice · macdice · commit faee3185aafa · 2025-01-09T16:05:01.000+13:00
walmethods.c used off_t to navigate around a pg_wal.tar file that could exceed 2GB, which doesn't work on Windows and would fail with misleading errors. Use pgoff_t instead. Back-patch to all supported branches. Author: Davinder Singh <davinder.singh@enterprisedb.com> Reported-by: Jakub Wartak <jakub.wartak@enterprisedb.com> Discussion: https://postgr.es/m/CAKZiRmyM4YnokK6Oenw5JKwAQ3rhP0YTz2T-tiw5dAQjGRXE3Q%40mail.gmail.com
diff --git a/src/bin/pg_basebackup/receivelog.c b/src/bin/pg_basebackup/receivelog.c
@@ -192,7 +192,7 @@ static bool
 close_walfile(StreamCtl *stream, XLogRecPtr pos)
 {
 	char	   *fn;
-	off_t		currpos;
+	pgoff_t		currpos;
 	int			r;
 	char		walfile_name[MAXPGPATH];
 
diff --git a/src/bin/pg_basebackup/walmethods.c b/src/bin/pg_basebackup/walmethods.c
@@ -691,7 +691,7 @@ const WalWriteMethodOps WalTarMethodOps = {
 typedef struct TarMethodFile
 {
 	Walfile		base;
-	off_t		ofs_start;		/* Where does the *header* for this file start */
+	pgoff_t		ofs_start;		/* Where does the *header* for this file start */
 	char		header[TAR_BLOCK_SIZE];
 	size_t		pad_to_size;
 } TarMethodFile;
diff --git a/src/bin/pg_basebackup/walmethods.h b/src/bin/pg_basebackup/walmethods.h
@@ -17,7 +17,7 @@ typedef struct WalWriteMethod WalWriteMethod;
 typedef struct
 {
 	WalWriteMethod *wwmethod;
-	off_t		currpos;
+	pgoff_t		currpos;
 	char	   *pathname;
 
 	/*

Original file line number	Diff line number	Diff line change
`@@ -192,7 +192,7 @@ static bool`
`192`	`192`	`close_walfile(StreamCtl *stream, XLogRecPtr pos)`
`193`	`193`	`{`
`194`	`194`	`char *fn;`
`195`		`- off_t currpos;`
	`195`	`+ pgoff_t currpos;`
`196`	`196`	`int r;`
`197`	`197`	`char walfile_name[MAXPGPATH];`
`198`	`198`
Original file line number	Diff line number	Diff line change
`@@ -691,7 +691,7 @@ const WalWriteMethodOps WalTarMethodOps = {`
`691`	`691`	`typedef struct TarMethodFile`
`692`	`692`	`{`
`693`	`693`	`Walfile base;`
`694`		`- off_t ofs_start; /* Where does the header for this file start */`
	`694`	`+ pgoff_t ofs_start; /* Where does the header for this file start */`
`695`	`695`	`char header[TAR_BLOCK_SIZE];`
`696`	`696`	`size_t pad_to_size;`
`697`	`697`	`} TarMethodFile;`
Original file line number	Diff line number	Diff line change
`@@ -17,7 +17,7 @@ typedef struct WalWriteMethod WalWriteMethod;`
`17`	`17`	`typedef struct`
`18`	`18`	`{`
`19`	`19`	`WalWriteMethod *wwmethod;`
`20`		`- off_t currpos;`
	`20`	`+ pgoff_t currpos;`
`21`	`21`	`char *pathname;`
`22`	`22`
`23`	`23`	`/*`