Commit 12366629 authored by evgen@moonbone.local's avatar evgen@moonbone.local
Browse files

Bug#29856: Insufficient buffer space led to a server crash.

The subst_spvars function is used to create query string with SP variables 
substituted with their values. This string is used later for the binary log
and for the query cache. The problem is that the
query_cache_send_result_to_client function requires some additional space
after the query to store database name and query cache flags. This 
space wasn't reserved by the subst_spvars function which led to a memory
corruption and crash.

Now the subst_spvars function reserves additional space for the query cache.
parent 4f579b8d
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+119 −0
Original line number Diff line number Diff line
@@ -1467,3 +1467,122 @@ insert into t1 values ('c');
a
drop table t1;
set GLOBAL query_cache_size= default;
SET GLOBAL query_cache_size=64*1024*1024;
CREATE TABLE t1 (id INT);
CREATE PROCEDURE proc29856(IN theUPC TEXT)
BEGIN
SET @stmtStr := '';
SELECT CONCAT("SELECT id FROM t1 WHERE id IN (",theUPC,")") INTO @stmtStr;
PREPARE stmt FROM @stmtStr;
EXECUTE stmt;
END |
CALL proc29856('1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,
25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,
51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,
77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,
102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,
121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,
140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,
159,160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,
178,179,180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,
197,198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,
216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,234,
235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,252,253,
254,255,256,257,258,259,260,261,262,263,264,265,266,267,268,269,270,271,272,
273,274,275,276,277,278,279,280,281,282,283,284,285,286,287,288,289,290,291,
292,293,294,295,296,297,298,299,300,301,302,303,304,305,306,307,308,309,310,
311,312,313,314,315,316,317,318,319,320,321,322,323,324,325,326,327,328,329,
330,331,332,333,334,335,336,337,338,339,340,341,342,343,344,345,346,347,348,
349,350,351,352,353,354,355,356,357,358,359,360,361,362,363,364,365,366,367,
368,369,370,371,372,373,374,375,376,377,378,379,380,381,382,383,384,385,386,
387,388,389,390,391,392,393,394,395,396,397,398,399,400,401,402,403,404,405,
406,407,408,409,410,411,412,413,414,415,416,417,418,419,420,421,422,423,424,
425,426,427,428,429,430,431,432,433,434,435,436,437,438,439,440,441,442,443,
444,445,446,447,448,449,450,451,452,453,454,455,456,457,458,459,460,461,462,
463,464,465,466,467,468,469,470,471,472,473,474,475,476,477,478,479,480,481,
482,483,484,485,486,487,488,489,490,491,492,493,494,495,496,497,498,499,500,
501,502,503,504,505,506,507,508,509,510,511,512,513,514,515,516,517,518,519,
520,521,522,523,524,525,526,527,528,529,530,531,532,533,534,535,536,537,538,
539,540,541,542,543,544,545,546,547,548,549,550,551,552,553,554,555,556,557,
558,559,560,561,562,563,564,565,566,567,568,569,570,571,572,573,574,575,576,
577,578,579,580,581,582,583,584,585,586,587,588,589,590,591,592,593,594,595,
596,597,598,599,600,601,602,603,604,605,606,607,608,609,610,611,612,613,614,
615,616,617,618,619,620,621,622,623,624,625,626,627,628,629,630,631,632,633,
634,635,636,637,638,639,640,641,642,643,644,645,646,647,648,649,650,651,652,
653,654,655,656,657,658,659,660,661,662,663,664,665,666,667,668,669,670,671,
672,673,674,675,676,677,678,679,680,681,682,683,684,685,686,687,688,689,690,
691,692,693,694,695,696,697,698,699,700,701,702,703,704,705,706,707,708,709,
710,711,712,713,714,715,716,717,718,719,720,721,722,723,724,725,726,727,728,
729,730,731,732,733,734,735,736,737,738,739,740,741,742,743,744,745,746,747,
748,749,750,751,752,753,754,755,756,757,758,759,760,761,762,763,764,765,766,
767,768,769,770,771,772,773,774,775,776,777,778,779,780,781,782,783,784,785,
786,787,788,789,790,791,792,793,794,795,796,797,798,799,800,801,802,803,804,
805,806,807,808,809,810,811,812,813,814,815,816,817,818,819,820,821,822,823,
824,825,826,827,828,829,830,831,832,833,834,835,836,837,838,839,840,841,842,
843,844,845,846,847,848,849,850,851,852,853,854,855,856,857,858,859,860,861,
862,863,864,865,866,867,868,869,870,871,872,873,874,875,876,877,878,879,880,
881,882,883,884,885,886,887,888,889,890,891,892,893,894,895,896,897,898,899,
900,901,902,903,904,905,906,907,908,909,910,911,912,913,914,915,916,917,918,
919,920,921,922,923,924,925,926,927,928,929,930,931,932,933,934,935,936,937,
938,939,940,941,942,943,944,945,946,947,948,949,950,951,952,953,954,955,956,
957,958,959,960,961,962,963,964,965,966,967,968,969,970,971,972,973,974,975,
976,977,978,979,980,981,982,983,984,985,986,987,988,989,990,991,992,993,994,
995,996,997,998,999,1000,1001,1002,1003,1004,1005,1006,1007,1008,1009,1010,
1011,1012,1013,1014,1015,1016,1017,1018,1019,1020,1021,1022,1023,1024,1025,
1026,1027,1028,1029,1030,1031,1032,1033,1034,1035,1036,1037,1038,1039,1040,
1041,1042,1043,1044,1045,1046,1047,1048,1049,1050,1051,1052,1053,1054,1055,
1056,1057,1058,1059,1060,1061,1062,1063,1064,1065,1066,1067,1068,1069,1070,
1071,1072,1073,1074,1075,1076,1077,1078,1079,1080,1081,1082,1083,1084,1085,
1086,1087,1088,1089,1090,1091,1092,1093,1094,1095,1096,1097,1098,1099,1100,
1101,1102,1103,1104,1105,1106,1107,1108,1109,1110,1111,1112,1113,1114,1115,
1116,1117,1118,1119,1120,1121,1122,1123,1124,1125,1126,1127,1128,1129,1130,
1131,1132,1133,1134,1135,1136,1137,1138,1139,1140,1141,1142,1143,1144,1145,
1146,1147,1148,1149,1150,1151,1152,1153,1154,1155,1156,1157,1158,1159,1160,
1161,1162,1163,1164,1165,1166,1167,1168,1169,1170,1171,1172,1173,1174,1175,
1176,1177,1178,1179,1180,1181,1182,1183,1184,1185,1186,1187,1188,1189,1190,
1191,1192,1193,1194,1195,1196,1197,1198,1199,1200,1201,1202,1203,1204,1205,
1206,1207,1208,1209,1210,1211,1212,1213,1214,1215,1216,1217,1218,1219,1220,
1221,1222,1223,1224,1225,1226,1227,1228,1229,1230,1231,1232,1233,1234,1235,
1236,1237,1238,1239,1240,1241,1242,1243,1244,1245,1246,1247,1248,1249,1250,
1251,1252,1253,1254,1255,1256,1257,1258,1259,1260,1261,1262,1263,1264,1265,
1266,1267,1268,1269,1270,1271,1272,1273,1274,1275,1276,1277,1278,1279,1280,
1281,1282,1283,1284,1285,1286,1287,1288,1289,1290,1291,1292,1293,1294,1295,
1296,1297,1298,1299,1300,1301,1302,1303,1304,1305,1306,1307,1308,1309,1310,
1311,1312,1313,1314,1315,1316,1317,1318,1319,1320,1321,1322,1323,1324,1325,
1326,1327,1328,1329,1330,1331,1332,1333,1334,1335,1336,1337,1338,1339,1340,
1341,1342,1343,1344,1345,1346,1347,1348,1349,1350,1351,1352,1353,1354,1355,
1356,1357,1358,1359,1360,1361,1362,1363,1364,1365,1366,1367,1368,1369,1370,
1371,1372,1373,1374,1375,1376,1377,1378,1379,1380,1381,1382,1383,1384,1385,
1386,1387,1388,1389,1390,1391,1392,1393,1394,1395,1396,1397,1398,1399,1400,
1401,1402,1403,1404,1405,1406,1407,1408,1409,1410,1411,1412,1413,1414,1415,
1416,1417,1418,1419,1420,1421,1422,1423,1424,1425,1426,1427,1428,1429,1430,
1431,1432,1433,1434,1435,1436,1437,1438,1439,1440,1441,1442,1443,1444,1445,
1446,1447,1448,1449,1450,1451,1452,1453,1454,1455,1456,1457,1458,1459,1460,
1461,1462,1463,1464,1465,1466,1467,1468,1469,1470,1471,1472,1473,1474,1475,
1476,1477,1478,1479,1480,1481,1482,1483,1484,1485,1486,1487,1488,1489,1490,
1491,1492,1493,1494,1495,1496,1497,1498,1499,1500,1501,1502,1503,1504,1505,
1506,1507,1508,1509,1510,1511,1512,1513,1514,1515,1516,1517,1518,1519,1520,
1521,1522,1523,1524,1525,1526,1527,1528,1529,1530,1531,1532,1533,1534,1535,
1536,1537,1538,1539,1540,1541,1542,1543,1544,1545,1546,1547,1548,1549,1550,
1551,1552,1553,1554,1555,1556,1557,1558,1559,1560,1561,1562,1563,1564,1565,
1566,1567,1568,1569,1570,1571,1572,1573,1574,1575,1576,1577,1578,1579,1580,
1581,1582,1583,1584,1585,1586,1587,1588,1589,1590,1591,1592,1593,1594,1595,
1596,1597,1598,1599,1600,1601,1602,1603,1604,1605,1606,1607,1608,1609,1610,
1611,1612,1613,1614,1615,1616,1617,1618,1619,1620,1621,1622,1623,1624,1625,
1626,1627,1628,1629,1630,1631,1632,1633,1634,1635,1636,1637,1638,1639,1640,
1641,1642,1643,1644,1645,1646,1647,1648,1649,1650,1651,1652,1653,1654,1655,
1656,1657,1658,1659,1660,1661,1662,1663,1664,1665,1666,1667,1668,1669,1670,
1671,1672,1673,1674,1675,1676,1677,1678,1679,1680,1681,1682,1683,1684,1685,
1686,1687,1688,1689,1690,1691,1692,1693,1694,1695,1696,1697,1698,1699,1700,
1701,1702,1703,1704,1705,1706,1707,1708,1709,1710,1711,1712,1713,1714,1715,
1716,1717,1718,1719,1720,1721,1722,1723,1724,1725,1726,1727,1728,1729,1730,
1731,1732,1733,1734,1735,1736,1737,1738,1739,1740,1741,1742,1743,1744,1745,
1746,1747,1748,1749,1750,1751,1752,1753,1754,1755,1756,1757,1758,1759,1760,
1761,1762,1763,1764,1765,1766,1767,1768,1769,1770,1771,1772,1773,1774,1775,
1776,1777,1778,1779,1780,1781,1782,1783,1784,1785,1786,1787,1788,1789,1790,
1791,1792,1793,1794,1795,1796,1797,1798,1799,1800,1801,1802,1803,1804,1805,
1806,1807,1808,1809,1810,1811');
id
DROP PROCEDURE proc29856;
DROP TABLE t1;
SET GLOBAL query_cache_size= default;
+124 −0
Original line number Diff line number Diff line
@@ -1028,4 +1028,128 @@ drop table t1;

set GLOBAL query_cache_size= default;

#
# Bug#29856: Insufficient buffer space led to a server crash.
#
SET GLOBAL query_cache_size=64*1024*1024;
CREATE TABLE t1 (id INT);
DELIMITER |;
CREATE PROCEDURE proc29856(IN theUPC TEXT)
BEGIN
  SET @stmtStr := '';
  SELECT CONCAT("SELECT id FROM t1 WHERE id IN (",theUPC,")") INTO @stmtStr;
  PREPARE stmt FROM @stmtStr;
  EXECUTE stmt;
END |
DELIMITER ;|
CALL proc29856('1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,
25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,
51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,
77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,
102,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,
121,122,123,124,125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,
140,141,142,143,144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,
159,160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,
178,179,180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,
197,198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,
216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,234,
235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,252,253,
254,255,256,257,258,259,260,261,262,263,264,265,266,267,268,269,270,271,272,
273,274,275,276,277,278,279,280,281,282,283,284,285,286,287,288,289,290,291,
292,293,294,295,296,297,298,299,300,301,302,303,304,305,306,307,308,309,310,
311,312,313,314,315,316,317,318,319,320,321,322,323,324,325,326,327,328,329,
330,331,332,333,334,335,336,337,338,339,340,341,342,343,344,345,346,347,348,
349,350,351,352,353,354,355,356,357,358,359,360,361,362,363,364,365,366,367,
368,369,370,371,372,373,374,375,376,377,378,379,380,381,382,383,384,385,386,
387,388,389,390,391,392,393,394,395,396,397,398,399,400,401,402,403,404,405,
406,407,408,409,410,411,412,413,414,415,416,417,418,419,420,421,422,423,424,
425,426,427,428,429,430,431,432,433,434,435,436,437,438,439,440,441,442,443,
444,445,446,447,448,449,450,451,452,453,454,455,456,457,458,459,460,461,462,
463,464,465,466,467,468,469,470,471,472,473,474,475,476,477,478,479,480,481,
482,483,484,485,486,487,488,489,490,491,492,493,494,495,496,497,498,499,500,
501,502,503,504,505,506,507,508,509,510,511,512,513,514,515,516,517,518,519,
520,521,522,523,524,525,526,527,528,529,530,531,532,533,534,535,536,537,538,
539,540,541,542,543,544,545,546,547,548,549,550,551,552,553,554,555,556,557,
558,559,560,561,562,563,564,565,566,567,568,569,570,571,572,573,574,575,576,
577,578,579,580,581,582,583,584,585,586,587,588,589,590,591,592,593,594,595,
596,597,598,599,600,601,602,603,604,605,606,607,608,609,610,611,612,613,614,
615,616,617,618,619,620,621,622,623,624,625,626,627,628,629,630,631,632,633,
634,635,636,637,638,639,640,641,642,643,644,645,646,647,648,649,650,651,652,
653,654,655,656,657,658,659,660,661,662,663,664,665,666,667,668,669,670,671,
672,673,674,675,676,677,678,679,680,681,682,683,684,685,686,687,688,689,690,
691,692,693,694,695,696,697,698,699,700,701,702,703,704,705,706,707,708,709,
710,711,712,713,714,715,716,717,718,719,720,721,722,723,724,725,726,727,728,
729,730,731,732,733,734,735,736,737,738,739,740,741,742,743,744,745,746,747,
748,749,750,751,752,753,754,755,756,757,758,759,760,761,762,763,764,765,766,
767,768,769,770,771,772,773,774,775,776,777,778,779,780,781,782,783,784,785,
786,787,788,789,790,791,792,793,794,795,796,797,798,799,800,801,802,803,804,
805,806,807,808,809,810,811,812,813,814,815,816,817,818,819,820,821,822,823,
824,825,826,827,828,829,830,831,832,833,834,835,836,837,838,839,840,841,842,
843,844,845,846,847,848,849,850,851,852,853,854,855,856,857,858,859,860,861,
862,863,864,865,866,867,868,869,870,871,872,873,874,875,876,877,878,879,880,
881,882,883,884,885,886,887,888,889,890,891,892,893,894,895,896,897,898,899,
900,901,902,903,904,905,906,907,908,909,910,911,912,913,914,915,916,917,918,
919,920,921,922,923,924,925,926,927,928,929,930,931,932,933,934,935,936,937,
938,939,940,941,942,943,944,945,946,947,948,949,950,951,952,953,954,955,956,
957,958,959,960,961,962,963,964,965,966,967,968,969,970,971,972,973,974,975,
976,977,978,979,980,981,982,983,984,985,986,987,988,989,990,991,992,993,994,
995,996,997,998,999,1000,1001,1002,1003,1004,1005,1006,1007,1008,1009,1010,
1011,1012,1013,1014,1015,1016,1017,1018,1019,1020,1021,1022,1023,1024,1025,
1026,1027,1028,1029,1030,1031,1032,1033,1034,1035,1036,1037,1038,1039,1040,
1041,1042,1043,1044,1045,1046,1047,1048,1049,1050,1051,1052,1053,1054,1055,
1056,1057,1058,1059,1060,1061,1062,1063,1064,1065,1066,1067,1068,1069,1070,
1071,1072,1073,1074,1075,1076,1077,1078,1079,1080,1081,1082,1083,1084,1085,
1086,1087,1088,1089,1090,1091,1092,1093,1094,1095,1096,1097,1098,1099,1100,
1101,1102,1103,1104,1105,1106,1107,1108,1109,1110,1111,1112,1113,1114,1115,
1116,1117,1118,1119,1120,1121,1122,1123,1124,1125,1126,1127,1128,1129,1130,
1131,1132,1133,1134,1135,1136,1137,1138,1139,1140,1141,1142,1143,1144,1145,
1146,1147,1148,1149,1150,1151,1152,1153,1154,1155,1156,1157,1158,1159,1160,
1161,1162,1163,1164,1165,1166,1167,1168,1169,1170,1171,1172,1173,1174,1175,
1176,1177,1178,1179,1180,1181,1182,1183,1184,1185,1186,1187,1188,1189,1190,
1191,1192,1193,1194,1195,1196,1197,1198,1199,1200,1201,1202,1203,1204,1205,
1206,1207,1208,1209,1210,1211,1212,1213,1214,1215,1216,1217,1218,1219,1220,
1221,1222,1223,1224,1225,1226,1227,1228,1229,1230,1231,1232,1233,1234,1235,
1236,1237,1238,1239,1240,1241,1242,1243,1244,1245,1246,1247,1248,1249,1250,
1251,1252,1253,1254,1255,1256,1257,1258,1259,1260,1261,1262,1263,1264,1265,
1266,1267,1268,1269,1270,1271,1272,1273,1274,1275,1276,1277,1278,1279,1280,
1281,1282,1283,1284,1285,1286,1287,1288,1289,1290,1291,1292,1293,1294,1295,
1296,1297,1298,1299,1300,1301,1302,1303,1304,1305,1306,1307,1308,1309,1310,
1311,1312,1313,1314,1315,1316,1317,1318,1319,1320,1321,1322,1323,1324,1325,
1326,1327,1328,1329,1330,1331,1332,1333,1334,1335,1336,1337,1338,1339,1340,
1341,1342,1343,1344,1345,1346,1347,1348,1349,1350,1351,1352,1353,1354,1355,
1356,1357,1358,1359,1360,1361,1362,1363,1364,1365,1366,1367,1368,1369,1370,
1371,1372,1373,1374,1375,1376,1377,1378,1379,1380,1381,1382,1383,1384,1385,
1386,1387,1388,1389,1390,1391,1392,1393,1394,1395,1396,1397,1398,1399,1400,
1401,1402,1403,1404,1405,1406,1407,1408,1409,1410,1411,1412,1413,1414,1415,
1416,1417,1418,1419,1420,1421,1422,1423,1424,1425,1426,1427,1428,1429,1430,
1431,1432,1433,1434,1435,1436,1437,1438,1439,1440,1441,1442,1443,1444,1445,
1446,1447,1448,1449,1450,1451,1452,1453,1454,1455,1456,1457,1458,1459,1460,
1461,1462,1463,1464,1465,1466,1467,1468,1469,1470,1471,1472,1473,1474,1475,
1476,1477,1478,1479,1480,1481,1482,1483,1484,1485,1486,1487,1488,1489,1490,
1491,1492,1493,1494,1495,1496,1497,1498,1499,1500,1501,1502,1503,1504,1505,
1506,1507,1508,1509,1510,1511,1512,1513,1514,1515,1516,1517,1518,1519,1520,
1521,1522,1523,1524,1525,1526,1527,1528,1529,1530,1531,1532,1533,1534,1535,
1536,1537,1538,1539,1540,1541,1542,1543,1544,1545,1546,1547,1548,1549,1550,
1551,1552,1553,1554,1555,1556,1557,1558,1559,1560,1561,1562,1563,1564,1565,
1566,1567,1568,1569,1570,1571,1572,1573,1574,1575,1576,1577,1578,1579,1580,
1581,1582,1583,1584,1585,1586,1587,1588,1589,1590,1591,1592,1593,1594,1595,
1596,1597,1598,1599,1600,1601,1602,1603,1604,1605,1606,1607,1608,1609,1610,
1611,1612,1613,1614,1615,1616,1617,1618,1619,1620,1621,1622,1623,1624,1625,
1626,1627,1628,1629,1630,1631,1632,1633,1634,1635,1636,1637,1638,1639,1640,
1641,1642,1643,1644,1645,1646,1647,1648,1649,1650,1651,1652,1653,1654,1655,
1656,1657,1658,1659,1660,1661,1662,1663,1664,1665,1666,1667,1668,1669,1670,
1671,1672,1673,1674,1675,1676,1677,1678,1679,1680,1681,1682,1683,1684,1685,
1686,1687,1688,1689,1690,1691,1692,1693,1694,1695,1696,1697,1698,1699,1700,
1701,1702,1703,1704,1705,1706,1707,1708,1709,1710,1711,1712,1713,1714,1715,
1716,1717,1718,1719,1720,1721,1722,1723,1724,1725,1726,1727,1728,1729,1730,
1731,1732,1733,1734,1735,1736,1737,1738,1739,1740,1741,1742,1743,1744,1745,
1746,1747,1748,1749,1750,1751,1752,1753,1754,1755,1756,1757,1758,1759,1760,
1761,1762,1763,1764,1765,1766,1767,1768,1769,1770,1771,1772,1773,1774,1775,
1776,1777,1778,1779,1780,1781,1782,1783,1784,1785,1786,1787,1788,1789,1790,
1791,1792,1793,1794,1795,1796,1797,1798,1799,1800,1801,1802,1803,1804,1805,
1806,1807,1808,1809,1810,1811');
DROP PROCEDURE proc29856;
DROP TABLE t1;
SET GLOBAL query_cache_size= default;

# End of 5.0 tests
+78 −66
Original line number Diff line number Diff line
@@ -767,7 +767,8 @@ int cmp_splocal_locations(Item_splocal * const *a, Item_splocal * const *b)


/*
  Replace thd->query{_length} with a string that one can write to the binlog.
  Replace thd->query{_length} with a string that one can write to the binlog
  or the query cache.
 
  SYNOPSIS
    subst_spvars()
@@ -779,7 +780,9 @@ int cmp_splocal_locations(Item_splocal * const *a, Item_splocal * const *b)
  DESCRIPTION

  The binlog-suitable string is produced by replacing references to SP local 
  variables with NAME_CONST('sp_var_name', value) calls.
  variables with NAME_CONST('sp_var_name', value) calls. To make this string
  suitable for the query cache this function allocates some additional space
  for the query cache flags.
 
  RETURN
    FALSE  on success
@@ -792,12 +795,11 @@ static bool
subst_spvars(THD *thd, sp_instr *instr, LEX_STRING *query_str)
{
  DBUG_ENTER("subst_spvars");
  if (thd->prelocked_mode == NON_PRELOCKED && mysql_bin_log.is_open())
  {

  Dynamic_array<Item_splocal*> sp_vars_uses;
  char *pbuf, *cur, buffer[512];
  String qbuf(buffer, sizeof(buffer), &my_charset_bin);
    int prev_pos, res;
  int prev_pos, res, buf_len;

  /* Find all instances of Item_splocal used in this statement */
  for (Item *item= instr->free_list; item; item= item->next)
@@ -860,12 +862,22 @@ subst_spvars(THD *thd, sp_instr *instr, LEX_STRING *query_str)
  if (res)
    DBUG_RETURN(TRUE);

    if (!(pbuf= thd->strmake(qbuf.ptr(), qbuf.length())))
  /*
    Allocate additional space at the end of the new query string for the
    query_cache_send_result_to_client function.
  */
  buf_len= qbuf.length() + thd->db_length + 1 + QUERY_CACHE_FLAGS_SIZE + 1;
  if ((pbuf= alloc_root(thd->mem_root, buf_len)))
  {
    memcpy(pbuf, qbuf.ptr(), qbuf.length());
    pbuf[qbuf.length()]= 0;
  }
  else
    DBUG_RETURN(TRUE);

  thd->query= pbuf;
  thd->query_length= qbuf.length();
  }

  DBUG_RETURN(FALSE);
}