Bug #5615
A memory leak in hash.c on Solaris (and every environment which defines __sun)
| Status: | Rejected | Start date: | 11/11/2011 | |
|---|---|---|---|---|
| Priority: | Normal | Due date: | ||
| Assignee: | - | % Done: | 0% |
|
| Category: | - | |||
| Target version: | 2.0.0 | |||
| ruby -v: | ruby 2.0.0dev (2011-11-11 trunk 33704) [i686-linux] |
Description
Reproducing steps: I didn't test the patch. Please do.
Result of `ruby -v`: ruby 2.0.0dev (2011-11-11 trunk 33704) [i686-linux]
What you expected: ruby should not have any memory leak.
What you happened: It seems to have a memory leak of ruby on Solaris.
The bug is in the function ruby_setenv() in hash.c.
Here is the code snippet around the bug:
2287 #elif defined __sun
2288 size_t len;
2289 char **env_ptr, *str;
2290 if (strchr(name, '=')) {
2291 errno = EINVAL;
2292 rb_sys_fail("ruby_setenv");
2293 }
2294 len = strlen(name);
2295 for (env_ptr = GET_ENVIRON(environ); (str = *env_ptr) != 0; ++env_ptr) {
2296 if (!strncmp(str, name, len) && str[len] == '=') {
2297 if (!in_origenv(str)) free(str);
2298 while ((env_ptr[0] = env_ptr[1]) != 0) env_ptr++;
2299 break;
2300 }
2301 }
2302 if (value) {
2303 str = malloc(len += strlen(value) + 2);
2304 snprintf(str, len, "%s=%s", name, value);
2305 if (putenv(str))
2306 rb_sys_fail("putenv");
2307 }
2308 #else /* WIN32 */
In line 2303, a variable 'str' is malloc-ed, but, seems never to free. Therefore it seems a memory leak.
This bug is found by using cppcheck technically.
Here is URL of cppcheck:
http://sourceforge.net/projects/cppcheck/
The result of cppcheck is following:
% cppcheck -f -I. hash.c
Checking hash.c...
Checking hash.c: ENV_IGNORECASE...
Checking hash.c: HAVE_SETENV;HAVE_UNSETENV...
Checking hash.c: _WIN32...
Checking hash.c: __APPLE__...
Checking hash.c: __sun...
[hash.c:2351]: (error) Memory leak: str
(information) Cppcheck cannot find all the include files (use --check-config for details)
I'll attach a patch to fix this bug. After applying this patch, cppcheck does not warn.
History
Updated by usa (Usaku NAKAMURA) 7 months ago
- Status changed from Open to Rejected
putenv(3)は引数で与えたポインタをそのまま使うので、この時点では解放することができません。
ちなみに、該当部分の少し上で(現時点のtrunkなら2297行目)
if (!in_origenv(str)) free(str);
というコードがありますが、これが不要になったら解放するコードになります。
# ということを、私も今回初めて知りました。