Fix memory leak with lower, upper and initcap with ICU-provided collations

The leak happens in str_tolower, str_toupper and str_initcap, which are
used in several places including their equivalent SQL-level functions,
and can only be triggered when using an ICU-provided collation when
converting the input string.

b615920 fixed a similar leak.  Backpatch down 10 where ICU collations
have been introduced.

Author: Konstantin Knizhnik
Discussion: https://postgr.es/m/94c0ad0a-cbc2-e4a3-7829-2bdeaf9146db@postgrespro.ru
Backpatch-through: 10

diff --git a/src/backend/utils/adt/formatting.c b/src/backend/utils/adt/formatting.c
index a345c656050760a0bf47d791747192e7f26f93f4..c8a9f939d6bbcfe751a3c3a843539f084d633fc7 100644 (file)
--- a/src/backend/utils/adt/formatting.c
+++ b/src/backend/utils/adt/formatting.c
@@ -1551,6 +1551,7 @@ str_tolower(const char *buff, size_t nbytes, Oid collid)
                                        &buff_conv, buff_uchar, len_uchar);
            icu_from_uchar(&result, buff_conv, len_conv);
            pfree(buff_uchar);
+           pfree(buff_conv);
        }
        else
 #endif
@@ -1673,6 +1674,7 @@ str_toupper(const char *buff, size_t nbytes, Oid collid)
                                        &buff_conv, buff_uchar, len_uchar);
            icu_from_uchar(&result, buff_conv, len_conv);
            pfree(buff_uchar);
+           pfree(buff_conv);
        }
        else
 #endif
@@ -1796,6 +1798,7 @@ str_initcap(const char *buff, size_t nbytes, Oid collid)
                                        &buff_conv, buff_uchar, len_uchar);
            icu_from_uchar(&result, buff_conv, len_conv);
            pfree(buff_uchar);
+           pfree(buff_conv);
        }
        else
 #endif