Avoid memory leak on error while parsing pg_stat_statements dump file

By using palloc() instead of raw malloc().

Reported-by: Gaurav Singh <gaurav.singh@yugabyte.com>
Reviewed-by: Lukas Fittl <lukas@fittl.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://www.postgresql.org/message-id/CAEcQ1bYR9s4eQLFDjzzJHU8fj-MTbmRpW-9J-r2gsCn+HEsynw@mail.gmail.com
Backpatch-through: 14
This commit is contained in:
Heikki Linnakangas 2026-03-27 12:20:38 +02:00
parent f421050015
commit 52edaf9d9b

View file

@ -784,7 +784,7 @@ pgss_shmem_shutdown(int code, Datum arg)
if (fwrite(&pgss->stats, sizeof(pgssGlobalStats), 1, file) != 1)
goto error;
free(qbuffer);
pfree(qbuffer);
qbuffer = NULL;
if (FreeFile(file))
@ -808,7 +808,8 @@ error:
(errcode_for_file_access(),
errmsg("could not write file \"%s\": %m",
PGSS_DUMP_FILE ".tmp")));
free(qbuffer);
if (qbuffer)
pfree(qbuffer);
if (file)
FreeFile(file);
unlink(PGSS_DUMP_FILE ".tmp");
@ -1669,7 +1670,8 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo,
pgss->extent != extent ||
pgss->gc_count != gc_count)
{
free(qbuffer);
if (qbuffer)
pfree(qbuffer);
qbuffer = qtext_load_file(&qbuffer_size);
}
}
@ -1853,7 +1855,8 @@ pg_stat_statements_internal(FunctionCallInfo fcinfo,
LWLockRelease(pgss->lock);
free(qbuffer);
if (qbuffer)
pfree(qbuffer);
}
/* Number of output arguments (columns) for pg_stat_statements_info */
@ -2158,7 +2161,7 @@ error:
}
/*
* Read the external query text file into a malloc'd buffer.
* Read the external query text file into a palloc'd buffer.
*
* Returns NULL (without throwing an error) if unable to read, eg
* file not there or insufficient memory.
@ -2200,7 +2203,7 @@ qtext_load_file(Size *buffer_size)
/* Allocate buffer; beware that off_t might be wider than size_t */
if (stat.st_size <= MaxAllocHugeSize)
buf = (char *) malloc(stat.st_size);
buf = (char *) palloc_extended(stat.st_size, MCXT_ALLOC_HUGE | MCXT_ALLOC_NO_OOM);
else
buf = NULL;
if (buf == NULL)
@ -2239,7 +2242,7 @@ qtext_load_file(Size *buffer_size)
(errcode_for_file_access(),
errmsg("could not read file \"%s\": %m",
PGSS_TEXT_FILE)));
free(buf);
pfree(buf);
CloseTransientFile(fd);
return NULL;
}
@ -2454,7 +2457,7 @@ gc_qtexts(void)
else
pgss->mean_query_len = ASSUMED_LENGTH_INIT;
free(qbuffer);
pfree(qbuffer);
/*
* OK, count a garbage collection cycle. (Note: even though we have
@ -2471,7 +2474,8 @@ gc_fail:
/* clean up resources */
if (qfile)
FreeFile(qfile);
free(qbuffer);
if (qbuffer)
pfree(qbuffer);
/*
* Since the contents of the external file are now uncertain, mark all