diff --git a/mysql-test/include/ctype_utf8mb4.inc b/mysql-test/include/ctype_utf8mb4.inc
index 71993a946b3..aa06cd97e4c 100644
--- a/mysql-test/include/ctype_utf8mb4.inc
+++ b/mysql-test/include/ctype_utf8mb4.inc
@@ -1576,7 +1576,7 @@ drop table t1;
 --echo #
 --echo # Check strnxfrm() with odd length
 --echo #
-set max_sort_length=5;
+set max_sort_length=9;
 select @@max_sort_length;
 eval create table t1 (a varchar(128) character set utf8mb4 collate utf8mb4_general_ci) engine $engine;
 insert into t1 values ('a'),('b'),('c');
diff --git a/mysql-test/r/ctype_utf16.result b/mysql-test/r/ctype_utf16.result
index c826a93809d..7c3d18a6cfc 100644
--- a/mysql-test/r/ctype_utf16.result
+++ b/mysql-test/r/ctype_utf16.result
@@ -1489,7 +1489,7 @@ ab
 ab
 AE
 AE
-SET max_sort_length=4;
+SET max_sort_length=8;
 SELECT * FROM t1 ORDER BY s1;
 s1
 ab
diff --git a/mysql-test/r/ctype_utf16le.result b/mysql-test/r/ctype_utf16le.result
index e1a71e02bb6..d129323bae0 100644
--- a/mysql-test/r/ctype_utf16le.result
+++ b/mysql-test/r/ctype_utf16le.result
@@ -1762,7 +1762,7 @@ ab
 ab
 AE
 AE
-SET max_sort_length=4;
+SET max_sort_length=8;
 SELECT * FROM t1 ORDER BY s1;
 s1
 ab
diff --git a/mysql-test/r/ctype_utf32.result b/mysql-test/r/ctype_utf32.result
index 4a44147e945..a4f7571d972 100644
--- a/mysql-test/r/ctype_utf32.result
+++ b/mysql-test/r/ctype_utf32.result
@@ -1503,7 +1503,7 @@ ab
 ab
 AE
 AE
-SET max_sort_length=4;
+SET max_sort_length=8;
 SELECT * FROM t1 ORDER BY s1;
 s1
 ab
diff --git a/mysql-test/r/ctype_utf8.result b/mysql-test/r/ctype_utf8.result
index 9ff12870d75..8b35305a79b 100644
--- a/mysql-test/r/ctype_utf8.result
+++ b/mysql-test/r/ctype_utf8.result
@@ -6807,10 +6807,10 @@ DFFFDFFF9CFF9DFF9EFF
 #
 # Checking strnxfrm() with odd length
 #
-set max_sort_length=5;
+set max_sort_length=9;
 select @@max_sort_length;
 @@max_sort_length
-5
+9
 create table t1 (a varchar(128) character set utf8 collate utf8_general_ci);
 insert into t1 values ('a'),('b'),('c');
 select * from t1 order by a;
diff --git a/mysql-test/r/ctype_utf8mb4.result b/mysql-test/r/ctype_utf8mb4.result
index fa1cf3b1d19..d7bc36119ec 100644
--- a/mysql-test/r/ctype_utf8mb4.result
+++ b/mysql-test/r/ctype_utf8mb4.result
@@ -2364,10 +2364,10 @@ drop table t1;
 #
 # Check strnxfrm() with odd length
 #
-set max_sort_length=5;
+set max_sort_length=9;
 select @@max_sort_length;
 @@max_sort_length
-5
+9
 create table t1 (a varchar(128) character set utf8mb4 collate utf8mb4_general_ci);
 insert into t1 values ('a'),('b'),('c');
 select * from t1 order by a;
diff --git a/mysql-test/r/ctype_utf8mb4_heap.result b/mysql-test/r/ctype_utf8mb4_heap.result
index ef134641ff8..9933c659ae3 100644
--- a/mysql-test/r/ctype_utf8mb4_heap.result
+++ b/mysql-test/r/ctype_utf8mb4_heap.result
@@ -2196,10 +2196,10 @@ drop table t1;
 #
 # Check strnxfrm() with odd length
 #
-set max_sort_length=5;
+set max_sort_length=9;
 select @@max_sort_length;
 @@max_sort_length
-5
+9
 create table t1 (a varchar(128) character set utf8mb4 collate utf8mb4_general_ci) engine heap;
 insert into t1 values ('a'),('b'),('c');
 select * from t1 order by a;
diff --git a/mysql-test/r/ctype_utf8mb4_innodb.result b/mysql-test/r/ctype_utf8mb4_innodb.result
index 9c58dc87126..ff8fe980247 100644
--- a/mysql-test/r/ctype_utf8mb4_innodb.result
+++ b/mysql-test/r/ctype_utf8mb4_innodb.result
@@ -2324,10 +2324,10 @@ drop table t1;
 #
 # Check strnxfrm() with odd length
 #
-set max_sort_length=5;
+set max_sort_length=9;
 select @@max_sort_length;
 @@max_sort_length
-5
+9
 create table t1 (a varchar(128) character set utf8mb4 collate utf8mb4_general_ci) engine InnoDB;
 insert into t1 values ('a'),('b'),('c');
 select * from t1 order by a;
diff --git a/mysql-test/r/ctype_utf8mb4_myisam.result b/mysql-test/r/ctype_utf8mb4_myisam.result
index 18bec51358d..b2e717a0737 100644
--- a/mysql-test/r/ctype_utf8mb4_myisam.result
+++ b/mysql-test/r/ctype_utf8mb4_myisam.result
@@ -2324,10 +2324,10 @@ drop table t1;
 #
 # Check strnxfrm() with odd length
 #
-set max_sort_length=5;
+set max_sort_length=9;
 select @@max_sort_length;
 @@max_sort_length
-5
+9
 create table t1 (a varchar(128) character set utf8mb4 collate utf8mb4_general_ci) engine MyISAM;
 insert into t1 values ('a'),('b'),('c');
 select * from t1 order by a;
diff --git a/mysql-test/r/order_by.result b/mysql-test/r/order_by.result
index 380687554d7..d35012e0de5 100644
--- a/mysql-test/r/order_by.result
+++ b/mysql-test/r/order_by.result
@@ -3237,3 +3237,68 @@ o	15
 p	16
 set @@sort_buffer_size= @save_sort_buffer_size;
 drop table t1;
+#
+# MDEV-22715: SIGSEGV in radixsort_for_str_ptr and in native_compare/my_qsort2 (optimized builds)
+#
+SET @save_sort_buffer_size= @@sort_buffer_size;
+SET @save_max_sort_length= @@max_sort_length;
+SET max_sort_length=8;
+SET sort_buffer_size=1024;
+CREATE TABLE t1(a INT, b DECIMAL(65), c BLOB);
+INSERT INTO t1 SELECT seq, seq, seq from seq_1_to_25;
+INSERT INTO t1 SELECT seq, seq, seq from seq_1_to_25;
+SELECT * FROM t1 ORDER BY a,b;
+a	b	c
+1	1	1
+1	1	1
+2	2	2
+2	2	2
+3	3	3
+3	3	3
+4	4	4
+4	4	4
+5	5	5
+5	5	5
+6	6	6
+6	6	6
+7	7	7
+7	7	7
+8	8	8
+8	8	8
+9	9	9
+9	9	9
+10	10	10
+10	10	10
+11	11	11
+11	11	11
+12	12	12
+12	12	12
+13	13	13
+13	13	13
+14	14	14
+14	14	14
+15	15	15
+15	15	15
+16	16	16
+16	16	16
+17	17	17
+17	17	17
+18	18	18
+18	18	18
+19	19	19
+19	19	19
+20	20	20
+20	20	20
+21	21	21
+21	21	21
+22	22	22
+22	22	22
+23	23	23
+23	23	23
+24	24	24
+24	24	24
+25	25	25
+25	25	25
+SET @@sort_buffer_size= @save_sort_buffer_size;
+SET @@max_sort_length= @save_max_sort_length;
+DROP TABLE t1;
diff --git a/mysql-test/suite/sys_vars/r/max_sort_length_basic.result b/mysql-test/suite/sys_vars/r/max_sort_length_basic.result
index a8876b2c81e..b48b045897c 100644
--- a/mysql-test/suite/sys_vars/r/max_sort_length_basic.result
+++ b/mysql-test/suite/sys_vars/r/max_sort_length_basic.result
@@ -27,14 +27,14 @@ SELECT @@session.max_sort_length = 1024;
 @@session.max_sort_length = 1024
 1
 '#--------------------FN_DYNVARS_084_03-------------------------#'
-SET @@global.max_sort_length = 4;
+SET @@global.max_sort_length = 8;
 SELECT @@global.max_sort_length;
 @@global.max_sort_length
-4
-SET @@global.max_sort_length = 5;
+8
+SET @@global.max_sort_length = 9;
 SELECT @@global.max_sort_length;
 @@global.max_sort_length
-5
+9
 SET @@global.max_sort_length = 8388608;
 SELECT @@global.max_sort_length;
 @@global.max_sort_length
@@ -48,14 +48,14 @@ SELECT @@global.max_sort_length;
 @@global.max_sort_length
 65536
 '#--------------------FN_DYNVARS_084_04-------------------------#'
-SET @@session.max_sort_length = 4;
+SET @@session.max_sort_length = 8;
 SELECT @@session.max_sort_length;
 @@session.max_sort_length
-4
-SET @@session.max_sort_length = 5;
+8
+SET @@session.max_sort_length = 9;
 SELECT @@session.max_sort_length;
 @@session.max_sort_length
-5
+9
 SET @@session.max_sort_length = 8388608;
 SELECT @@session.max_sort_length;
 @@session.max_sort_length
@@ -74,13 +74,13 @@ Warnings:
 Warning	1292	Truncated incorrect max_sort_length value: '-1024'
 SELECT @@global.max_sort_length;
 @@global.max_sort_length
-4
+8
 SET @@global.max_sort_length = 3;
 Warnings:
 Warning	1292	Truncated incorrect max_sort_length value: '3'
 SELECT @@global.max_sort_length;
 @@global.max_sort_length
-4
+8
 SET @@global.max_sort_length = 8388609;
 Warnings:
 Warning	1292	Truncated incorrect max_sort_length value: '8388609'
@@ -92,17 +92,17 @@ Warnings:
 Warning	1292	Truncated incorrect max_sort_length value: '0'
 SELECT @@global.max_sort_length;
 @@global.max_sort_length
-4
+8
 SET @@global.max_sort_length = 65530.34;
 ERROR 42000: Incorrect argument type to variable 'max_sort_length'
 SELECT @@global.max_sort_length;
 @@global.max_sort_length
-4
+8
 SET @@global.max_sort_length = test;
 ERROR 42000: Incorrect argument type to variable 'max_sort_length'
 SELECT @@global.max_sort_length;
 @@global.max_sort_length
-4
+8
 SET @@session.max_sort_length = 8388610;
 Warnings:
 Warning	1292	Truncated incorrect max_sort_length value: '8388610'
@@ -114,19 +114,19 @@ Warnings:
 Warning	1292	Truncated incorrect max_sort_length value: '-1'
 SELECT @@session.max_sort_length;
 @@session.max_sort_length
-4
+8
 SET @@session.max_sort_length = 3;
 Warnings:
 Warning	1292	Truncated incorrect max_sort_length value: '3'
 SELECT @@session.max_sort_length;
 @@session.max_sort_length
-4
+8
 SET @@session.max_sort_length = 0;
 Warnings:
 Warning	1292	Truncated incorrect max_sort_length value: '0'
 SELECT @@session.max_sort_length;
 @@session.max_sort_length
-4
+8
 SET @@session.max_sort_length = 65530.34;
 ERROR 42000: Incorrect argument type to variable 'max_sort_length'
 SET @@session.max_sort_length = 10737418241;
@@ -158,13 +158,13 @@ Warnings:
 Warning	1292	Truncated incorrect max_sort_length value: '1'
 SELECT @@global.max_sort_length;
 @@global.max_sort_length
-4
+8
 SET @@global.max_sort_length = FALSE;
 Warnings:
 Warning	1292	Truncated incorrect max_sort_length value: '0'
 SELECT @@global.max_sort_length;
 @@global.max_sort_length
-4
+8
 '#---------------------FN_DYNVARS_084_09----------------------#'
 SET @@global.max_sort_length = 2048;
 SELECT @@max_sort_length = @@global.max_sort_length;
diff --git a/mysql-test/suite/sys_vars/r/sysvars_server_embedded.result b/mysql-test/suite/sys_vars/r/sysvars_server_embedded.result
index 9ca6995d7ef..865b5a8ca2f 100644
--- a/mysql-test/suite/sys_vars/r/sysvars_server_embedded.result
+++ b/mysql-test/suite/sys_vars/r/sysvars_server_embedded.result
@@ -2033,7 +2033,7 @@ DEFAULT_VALUE	1024
 VARIABLE_SCOPE	SESSION
 VARIABLE_TYPE	BIGINT UNSIGNED
 VARIABLE_COMMENT	The number of bytes to use when sorting BLOB or TEXT values (only the first max_sort_length bytes of each value are used; the rest are ignored)
-NUMERIC_MIN_VALUE	4
+NUMERIC_MIN_VALUE	8
 NUMERIC_MAX_VALUE	8388608
 NUMERIC_BLOCK_SIZE	1
 ENUM_VALUE_LIST	NULL
diff --git a/mysql-test/suite/sys_vars/r/sysvars_server_notembedded.result b/mysql-test/suite/sys_vars/r/sysvars_server_notembedded.result
index 9288912eb57..21f1f905de8 100644
--- a/mysql-test/suite/sys_vars/r/sysvars_server_notembedded.result
+++ b/mysql-test/suite/sys_vars/r/sysvars_server_notembedded.result
@@ -2229,7 +2229,7 @@ DEFAULT_VALUE	1024
 VARIABLE_SCOPE	SESSION
 VARIABLE_TYPE	BIGINT UNSIGNED
 VARIABLE_COMMENT	The number of bytes to use when sorting BLOB or TEXT values (only the first max_sort_length bytes of each value are used; the rest are ignored)
-NUMERIC_MIN_VALUE	4
+NUMERIC_MIN_VALUE	8
 NUMERIC_MAX_VALUE	8388608
 NUMERIC_BLOCK_SIZE	1
 ENUM_VALUE_LIST	NULL
diff --git a/mysql-test/suite/sys_vars/t/max_sort_length_basic.test b/mysql-test/suite/sys_vars/t/max_sort_length_basic.test
index 9c3b88d3c3c..fcd6db017f1 100644
--- a/mysql-test/suite/sys_vars/t/max_sort_length_basic.test
+++ b/mysql-test/suite/sys_vars/t/max_sort_length_basic.test
@@ -74,9 +74,9 @@ SELECT @@session.max_sort_length = 1024;
 # Change the value of max_sort_length to a valid value for GLOBAL Scope #
 #########################################################################
 
-SET @@global.max_sort_length = 4;
+SET @@global.max_sort_length = 8;
 SELECT @@global.max_sort_length;
-SET @@global.max_sort_length = 5;
+SET @@global.max_sort_length = 9;
 SELECT @@global.max_sort_length;
 SET @@global.max_sort_length = 8388608;
 SELECT @@global.max_sort_length;
@@ -90,10 +90,10 @@ SELECT @@global.max_sort_length;
 # Change the value of max_sort_length to a valid value for SESSION Scope #
 ##########################################################################
 
-SET @@session.max_sort_length = 4;
+SET @@session.max_sort_length = 8;
 SELECT @@session.max_sort_length;
 
-SET @@session.max_sort_length = 5;
+SET @@session.max_sort_length = 9;
 SELECT @@session.max_sort_length;
 
 SET @@session.max_sort_length = 8388608;
diff --git a/mysql-test/t/ctype_utf16.test b/mysql-test/t/ctype_utf16.test
index 1febe3d8aea..28c31d639aa 100644
--- a/mysql-test/t/ctype_utf16.test
+++ b/mysql-test/t/ctype_utf16.test
@@ -721,7 +721,7 @@ CREATE TABLE t1 AS SELECT repeat('a',2) as s1 LIMIT 0;
 SHOW CREATE TABLE t1;
 INSERT INTO t1 VALUES ('ab'),('AE'),('ab'),('AE');
 SELECT * FROM t1 ORDER BY s1;
-SET max_sort_length=4;
+SET max_sort_length=8;
 SELECT * FROM t1 ORDER BY s1;
 DROP TABLE t1;
 SET max_sort_length=DEFAULT;
diff --git a/mysql-test/t/ctype_utf16le.test b/mysql-test/t/ctype_utf16le.test
index 5e29408cbd0..2a8aaeafe59 100644
--- a/mysql-test/t/ctype_utf16le.test
+++ b/mysql-test/t/ctype_utf16le.test
@@ -683,7 +683,7 @@ CREATE TABLE t1 AS SELECT REPEAT('a',2) as s1 LIMIT 0;
 SHOW CREATE TABLE t1;
 INSERT INTO t1 VALUES ('ab'),('AE'),('ab'),('AE');
 SELECT * FROM t1 ORDER BY s1;
-SET max_sort_length=4;
+SET max_sort_length=8;
 SELECT * FROM t1 ORDER BY s1;
 DROP TABLE t1;
 SET max_sort_length=DEFAULT;
diff --git a/mysql-test/t/ctype_utf32.test b/mysql-test/t/ctype_utf32.test
index bf822291a21..c7835e3c74f 100644
--- a/mysql-test/t/ctype_utf32.test
+++ b/mysql-test/t/ctype_utf32.test
@@ -778,7 +778,7 @@ CREATE TABLE t1 AS SELECT repeat('a',2) as s1 LIMIT 0;
 SHOW CREATE TABLE t1;
 INSERT INTO t1 VALUES ('ab'),('AE'),('ab'),('AE');
 SELECT * FROM t1 ORDER BY s1;
-SET max_sort_length=4;
+SET max_sort_length=8;
 SELECT * FROM t1 ORDER BY s1;
 DROP TABLE t1;
 SET max_sort_length=DEFAULT;
diff --git a/mysql-test/t/ctype_utf8.test b/mysql-test/t/ctype_utf8.test
index 51b6d63ee2f..7abcc693926 100644
--- a/mysql-test/t/ctype_utf8.test
+++ b/mysql-test/t/ctype_utf8.test
@@ -1756,7 +1756,7 @@ set @@collation_connection=utf8_bin;
 --echo #
 --echo # Checking strnxfrm() with odd length
 --echo #
-set max_sort_length=5;
+set max_sort_length=9;
 select @@max_sort_length;
 create table t1 (a varchar(128) character set utf8 collate utf8_general_ci);
 insert into t1 values ('a'),('b'),('c');
diff --git a/mysql-test/t/ctype_utf8mb4.test b/mysql-test/t/ctype_utf8mb4.test
index ffc098ff938..91256d6e096 100644
--- a/mysql-test/t/ctype_utf8mb4.test
+++ b/mysql-test/t/ctype_utf8mb4.test
@@ -1511,7 +1511,7 @@ drop table t1;
 --echo #
 --echo # Check strnxfrm() with odd length
 --echo #
-set max_sort_length=5;
+set max_sort_length=9;
 select @@max_sort_length;
 create table t1 (a varchar(128) character set utf8mb4 collate utf8mb4_general_ci);
 insert into t1 values ('a'),('b'),('c');
diff --git a/mysql-test/t/order_by.test b/mysql-test/t/order_by.test
index 999c7314139..2fbacb10b68 100644
--- a/mysql-test/t/order_by.test
+++ b/mysql-test/t/order_by.test
@@ -12,6 +12,8 @@ call mtr.add_suppression("Out of sort memory; increase server sort buffer size")
 # Test old ORDER BY bug
 #
 
+--source include/have_sequence.inc
+
 CREATE TABLE t1 (
   id int(6) DEFAULT '0' NOT NULL,
   idservice int(5),
@@ -2157,3 +2159,18 @@ select * from t1 order  by b;
 set @@sort_buffer_size= @save_sort_buffer_size;
 drop table t1;
 
+--echo #
+--echo # MDEV-22715: SIGSEGV in radixsort_for_str_ptr and in native_compare/my_qsort2 (optimized builds)
+--echo #
+
+SET @save_sort_buffer_size= @@sort_buffer_size;
+SET @save_max_sort_length= @@max_sort_length;
+SET max_sort_length=8;
+SET sort_buffer_size=1024;
+CREATE TABLE t1(a INT, b DECIMAL(65), c BLOB);
+INSERT INTO t1 SELECT seq, seq, seq from seq_1_to_25;
+INSERT INTO t1 SELECT seq, seq, seq from seq_1_to_25;
+SELECT * FROM t1 ORDER BY a,b;
+SET @@sort_buffer_size= @save_sort_buffer_size;
+SET @@max_sort_length= @save_max_sort_length;
+DROP TABLE t1;
diff --git a/sql/field.cc b/sql/field.cc
index 291e2134dcf..f65c6f88bb9 100644
--- a/sql/field.cc
+++ b/sql/field.cc
@@ -3295,10 +3295,9 @@ int Field_new_decimal::cmp(const uchar *a,const uchar*b)
 }
 
 
-void Field_new_decimal::sort_string(uchar *buff,
-                                    uint length __attribute__((unused)))
+void Field_new_decimal::sort_string(uchar *buff, uint length)
 {
-  memcpy(buff, ptr, bin_size);
+  memcpy(buff, ptr, length);
 }
 
 
diff --git a/sql/field.h b/sql/field.h
index 60849ea8099..5e8f39d903e 100644
--- a/sql/field.h
+++ b/sql/field.h
@@ -1099,6 +1099,13 @@ public:
 
   void make_sort_key(uchar *buff, uint length);
   virtual void make_field(Send_field *);
+
+  /*
+    Some implementations actually may write up to 8 bytes regardless of what
+    size was requested. This is due to the minimum value of the system variable
+    max_sort_length.
+  */
+
   virtual void sort_string(uchar *buff,uint length)=0;
   virtual bool optimize_range(uint idx, uint part);
   virtual void free() {}
diff --git a/sql/sys_vars.cc b/sql/sys_vars.cc
index 9f87c846fd0..7dc1d1ab6e8 100644
--- a/sql/sys_vars.cc
+++ b/sql/sys_vars.cc
@@ -2178,7 +2178,7 @@ static Sys_var_ulong Sys_max_sort_length(
        "the first max_sort_length bytes of each value are used; the rest "
        "are ignored)",
        SESSION_VAR(max_sort_length), CMD_LINE(REQUIRED_ARG),
-       VALID_RANGE(4, 8192*1024L), DEFAULT(1024), BLOCK_SIZE(1));
+       VALID_RANGE(8, 8192*1024L), DEFAULT(1024), BLOCK_SIZE(1));
 
 static Sys_var_ulong Sys_max_sp_recursion_depth(
        "max_sp_recursion_depth",