v2-0001-Check-return-value-of-pclose-correctly.patch

From 86b2b61d30f848b84c69437c7106dea8fdf3738d Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Tue, 8 Nov 2022 14:03:12 +0100
Subject: [PATCH v2] Check return value of pclose() correctly

Some callers didn't check the return value of pclose() or
ClosePipeStream() correctly.  Either they didn't check it at all or
they treated it like the return of fclose().

The correct way is to first check whether the return value is -1, and
then report errno, and then check the return value like a result from
system(), for which we already have wait_result_to_str() to make it
simpler.  To make this more compact, expand wait_result_to_str() to
also handle -1 explicitly.

Discussion: https://www.postgresql.org/message-id/flat/8cd9fb02-bc26-65f1-a809-b1cb360eef73@enterprisedb.com
---
 src/backend/commands/collationcmds.c | 11 ++++++++++-
 src/bin/pg_ctl/pg_ctl.c              |  3 +--
 src/bin/pg_upgrade/controldata.c     | 12 +++++++++---
 src/bin/pg_upgrade/exec.c            |  6 +++++-
 src/bin/pg_upgrade/option.c          |  6 +++++-
 src/bin/pgbench/pgbench.c            |  2 +-
 src/bin/psql/command.c               | 18 ++++++++++++++----
 src/common/wait_error.c              |  6 +++++-
 8 files changed, 50 insertions(+), 14 deletions(-)

diff --git a/src/backend/commands/collationcmds.c b/src/backend/commands/collationcmds.c
index 86fbc7fa019f..fbf45f05aa0f 100644
--- a/src/backend/commands/collationcmds.c
+++ b/src/backend/commands/collationcmds.c
@@ -639,6 +639,7 @@ pg_import_system_collations(PG_FUNCTION_ARGS)
 		int			naliases,
 					maxaliases,
 					i;
+		int			pclose_rc;
 
 		/* expansible array of aliases */
 		maxaliases = 100;
@@ -745,7 +746,15 @@ pg_import_system_collations(PG_FUNCTION_ARGS)
 			}
 		}
 
-		ClosePipeStream(locale_a_handle);
+		pclose_rc = ClosePipeStream(locale_a_handle);
+		if (pclose_rc != 0)
+		{
+			ereport(ERROR,
+					(errcode_for_file_access(),
+					 errmsg("could not execute command \"%s\": %s",
+							"locale -a",
+							wait_result_to_str(pclose_rc))));
+		}
 
 		/*
 		 * Before processing the aliases, sort them by locale name.  The point
diff --git a/src/bin/pg_ctl/pg_ctl.c b/src/bin/pg_ctl/pg_ctl.c
index a509fc9109e8..ceab603c47d9 100644
--- a/src/bin/pg_ctl/pg_ctl.c
+++ b/src/bin/pg_ctl/pg_ctl.c
@@ -2154,12 +2154,11 @@ adjust_data_dir(void)
 	fflush(NULL);
 
 	fd = popen(cmd, "r");
-	if (fd == NULL || fgets(filename, sizeof(filename), fd) == NULL)
+	if (fd == NULL || fgets(filename, sizeof(filename), fd) == NULL || pclose(fd) != 0)
 	{
 		write_stderr(_("%s: could not determine the data directory using command \"%s\"\n"), progname, cmd);
 		exit(1);
 	}
-	pclose(fd);
 	free(my_exec_path);
 
 	/* strip trailing newline and carriage return */
diff --git a/src/bin/pg_upgrade/controldata.c b/src/bin/pg_upgrade/controldata.c
index 018cd310f7c8..73bfd14397cf 100644
--- a/src/bin/pg_upgrade/controldata.c
+++ b/src/bin/pg_upgrade/controldata.c
@@ -75,7 +75,7 @@ get_control_data(ClusterInfo *cluster, bool live_check)
 	uint32		logid = 0;
 	uint32		segno = 0;
 	char	   *resetwal_bin;
-
+	int			rc;
 
 	/*
 	 * Because we test the pg_resetwal output as strings, it has to be in
@@ -170,7 +170,10 @@ get_control_data(ClusterInfo *cluster, bool live_check)
 			}
 		}
 
-		pclose(output);
+		rc = pclose(output);
+		if (rc != 0)
+			pg_fatal("could not get control data using %s: %s",
+					 cmd, wait_result_to_str(rc));
 
 		if (!got_cluster_state)
 		{
@@ -500,7 +503,10 @@ get_control_data(ClusterInfo *cluster, bool live_check)
 		}
 	}
 
-	pclose(output);
+	rc = pclose(output);
+	if (rc != 0)
+		pg_fatal("could not get control data using %s: %s",
+				 cmd, wait_result_to_str(rc));
 
 	/*
 	 * Restore environment variables.  Note all but LANG and LC_MESSAGES were
diff --git a/src/bin/pg_upgrade/exec.c b/src/bin/pg_upgrade/exec.c
index 60f4b5443e68..23fe50e33d9c 100644
--- a/src/bin/pg_upgrade/exec.c
+++ b/src/bin/pg_upgrade/exec.c
@@ -35,6 +35,7 @@ get_bin_version(ClusterInfo *cluster)
 	char		cmd[MAXPGPATH],
 				cmd_output[MAX_STRING];
 	FILE	   *output;
+	int			rc;
 	int			v1 = 0,
 				v2 = 0;
 
@@ -46,7 +47,10 @@ get_bin_version(ClusterInfo *cluster)
 		pg_fatal("could not get pg_ctl version data using %s: %s",
 				 cmd, strerror(errno));
 
-	pclose(output);
+	rc = pclose(output);
+	if (rc != 0)
+		pg_fatal("could not get pg_ctl version data using %s: %s",
+				 cmd, wait_result_to_str(rc));
 
 	if (sscanf(cmd_output, "%*s %*s %d.%d", &v1, &v2) < 1)
 		pg_fatal("could not get pg_ctl version output from %s", cmd);
diff --git a/src/bin/pg_upgrade/option.c b/src/bin/pg_upgrade/option.c
index 3f719f1762c5..f441668c612a 100644
--- a/src/bin/pg_upgrade/option.c
+++ b/src/bin/pg_upgrade/option.c
@@ -384,6 +384,7 @@ adjust_data_dir(ClusterInfo *cluster)
 				cmd_output[MAX_STRING];
 	FILE	   *fp,
 			   *output;
+	int			rc;
 
 	/* Initially assume config dir and data dir are the same */
 	cluster->pgconfig = pg_strdup(cluster->pgdata);
@@ -423,7 +424,10 @@ adjust_data_dir(ClusterInfo *cluster)
 		pg_fatal("could not get data directory using %s: %s",
 				 cmd, strerror(errno));
 
-	pclose(output);
+	rc = pclose(output);
+	if (rc != 0)
+		pg_fatal("could not get control data directory using %s: %s",
+				 cmd, wait_result_to_str(rc));
 
 	/* strip trailing newline and carriage return */
 	(void) pg_strip_crlf(cmd_output);
diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c
index b208d74767f1..36905a896817 100644
--- a/src/bin/pgbench/pgbench.c
+++ b/src/bin/pgbench/pgbench.c
@@ -3002,7 +3002,7 @@ runShellCommand(Variables *variables, char *variable, char **argv, int argc)
 	}
 	if (pclose(fp) < 0)
 	{
-		pg_log_error("%s: could not close shell command", argv[0]);
+		pg_log_error("%s: could not run shell command: %m", argv[0]);
 		return false;
 	}
 
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index ab613dd49e0a..6958562e3340 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -2694,14 +2694,24 @@ exec_command_write(PsqlScanState scan_state, bool active_branch,
 				fprintf(fd, "%s\n", previous_buf->data);
 
 			if (is_pipe)
+			{
 				result = pclose(fd);
+
+				if (result != 0)
+				{
+					pg_log_error("%s: %s", fname, wait_result_to_str(result));
+					status = PSQL_CMD_ERROR;
+				}
+			}
 			else
+			{
 				result = fclose(fd);
 
-			if (result == EOF)
-			{
-				pg_log_error("%s: %m", fname);
-				status = PSQL_CMD_ERROR;
+				if (result == EOF)
+				{
+					pg_log_error("%s: %m", fname);
+					status = PSQL_CMD_ERROR;
+				}
 			}
 		}
 
diff --git a/src/common/wait_error.c b/src/common/wait_error.c
index a776f2901e8e..8397e238b2b4 100644
--- a/src/common/wait_error.c
+++ b/src/common/wait_error.c
@@ -33,7 +33,11 @@ wait_result_to_str(int exitstatus)
 {
 	char		str[512];
 
-	if (WIFEXITED(exitstatus))
+	if (exitstatus == -1)
+	{
+		snprintf(str, sizeof(str), "%m");
+	}
+	else if (WIFEXITED(exitstatus))
 	{
 		/*
 		 * Give more specific error message for some common exit codes that

base-commit: bd95816f74ad4cad3d2a3c160be426358d6cea51
-- 
2.38.1