| Bug #29687 | mysql_stmt_store_result memory leak in libmysqld | ||
|---|---|---|---|
| Submitted: | 10 Jul 2007 10:09 | Modified: | 23 Jul 2007 0:47 |
| Reporter: | Shane Bester (Platinum Quality Contributor) | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server: Prepared statements | Severity: | S1 (Critical) |
| Version: | 5.1.17, 5.1.20 | OS: | Any |
| Assigned to: | Alexey Botchkov | CPU Architecture: | Any |
| Tags: | memory leak, mysql_stmt_store_result | ||
[16 Jul 2007 15:08]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/30968 ChangeSet@1.2527, 2007-07-16 19:08:07+05:00, holyfoot@mysql.com +1 -0 Bug #29687 mysql_stmt_store_result memory leak in libmysqld In embedded server we use result->alloc to store field data for the result, but we didn't clean the result->alloc if the query returned an empty recordset. Cleaning for the empty recordset enabled
[20 Jul 2007 23:46]
Bugs System
Pushed into 5.1.21-beta
[20 Jul 2007 23:49]
Bugs System
Pushed into 5.0.48
[22 Jul 2007 17:58]
Paul DuBois
Noted in 5.0.48, 5.1.21 changelogs. The mysql_stmt_store_result() C API function caused a memory leak for empty result sets.
[22 Jul 2007 18:31]
Sergei Golubchik
in the embedded server - libmysqld - only
[23 Jul 2007 0:47]
Paul DuBois
Updated changelog to note embedded-server only.
Description: when calling mysql_stmt_store_result and there is no resultset to retrieve, a memory leak occurs. How to repeat: A test program: /* g++ -c -Wall -I/home/sbester/server/5.1/mysql-5.1.17-beta-linux-i686-glibc23/include leaker.c g++ -Wall -pthread -ldl -o leaker leaker.o /home/sbester/server/5.1/mysql-5.1.17-beta-linux-i686-glibc23/lib/libmysqld.a /usr/lib/libcrypt.a /usr/lib/libz.a */ #include <stdio.h> #include <unistd.h> #include <string.h> #include "mysql.h" static char *server_args[] = { "this_program", /* this string is not used */ "--basedir=/home/sbester/server/5.1/mysql-5.1.17-beta-linux-i686-glibc23/", "--key_buffer_size=32M" }; static char *server_groups[] = { "embedded", "server", "this_program_SERVER", (char *)NULL }; int main(int argc, char** argv) { MYSQL *m; MYSQL_STMT *s; char sql[]="SELECT 1 FROM dual WHERE 0=2"; if (mysql_library_init(sizeof(server_args) / sizeof(char *),server_args, server_groups)) { fprintf(stderr, "could not initialize MySQL library\n"); return 1; } m= mysql_init(NULL); mysql_real_connect(m,"","","","",0,NULL,0); s= mysql_stmt_init(m); mysql_stmt_prepare(s, sql, strlen(sql)); while(1) { mysql_stmt_execute(s); mysql_stmt_store_result(s); while (mysql_stmt_fetch(s)==0); mysql_stmt_free_result(s); } mysql_stmt_close(s); return 0; return 0; } Suggested fix: don't leak.