gh-144069: Fix memory leak in _dbm.open() on failure #144075
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VanshAgarwal24036
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serhiy-storchaka
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picnixz
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picnixz
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I fail to understand how this fixes the leak. Have you tried to run the reproducer case?
| self.addCleanup(cleaunup_test_dir) | ||
| setup_test_dir() | ||
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| def test_open_nonexistent_directory(self): |
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Can you put the test closer to other open()-tests? please be mindful of the quality of the PRs you submit.
| if (dp->di_dbm != NULL) { | ||
| dbm_close(dp->di_dbm); | ||
| dp->di_dbm = NULL; | ||
| } |
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No need for that, you can leave it to dealloc. In addition this code path will never be taken as di_dbm will be NULL... this is exactly your if test.
However add dp->di_dbm = NULL in dbm_dealloc() to prevent double frees.
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A Python core developer has requested some changes be made to your pull request before we can consider merging it. If you could please address their requests along with any other requests in other reviews from core developers that would be appreciated. Once you have made the requested changes, please leave a comment on this pull request containing the phrase |
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If dbm_open() may allocate internal DBM resources even if it returns NULL, we cannot do anything with this, because the returned values is the only way to access these resources.
| if ( (dp->di_dbm = dbm_open((char *)file, flags, mode)) == 0 ) { | ||
| if ( (dp->di_dbm = dbm_open((char *)file, flags, mode)) == NULL ) { | ||
| PyErr_SetFromErrnoWithFilename(state->dbm_error, file); | ||
| if (dp->di_dbm != NULL) { |
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Wait, we just tested that dp->di_dbm == NULL.
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gh-144069
Fix a memory leak in _dbm.open() when dbm_open() fails (for example when
attempting to create a database in a non-existent directory).
dbm_open() may allocate internal DBM resources even if it returns NULL.
Ensure that any partially allocated DBM handle is properly closed on
error paths to avoid leaking memory.
Add a regression test exercising dbm.open() on a path with a missing
parent directory.