lib/open: fix potential double-free, ensure *database=NULL on error

During refactoring for 0.32, the code that set notmuch=NULL on various
errors was moved into _finish_open. This meant that the the code which
relied on that to set *database to NULL on error was no longer
correct. It also introduced a potential double free, since the notmuch
struct was deallocated inside _finish_open (via n_d_destroy).

In this commit we revert to "allocator frees", and leave any cleanup
to the caller of _finish_open. This allows us to get back the
behaviour of setting *database to NULL with a small change. Other
callers of _finish_open will need free notmuch on errors.
This commit is contained in:
David Bremner 2021-10-23 10:22:34 -03:00
parent a942cb8ee3
commit 74c4ce6d88
2 changed files with 5 additions and 10 deletions

View file

@ -396,8 +396,6 @@ _finish_open (notmuch_database_t *notmuch,
" has a newer database format version (%u) than supported by this\n"
" version of notmuch (%u).\n",
database_path, version, NOTMUCH_DATABASE_VERSION));
notmuch_database_destroy (notmuch);
notmuch = NULL;
status = NOTMUCH_STATUS_FILE_ERROR;
goto DONE;
}
@ -414,8 +412,6 @@ _finish_open (notmuch_database_t *notmuch,
" requires features (%s)\n"
" not supported by this version of notmuch.\n",
database_path, incompat_features));
notmuch_database_destroy (notmuch);
notmuch = NULL;
status = NOTMUCH_STATUS_FILE_ERROR;
goto DONE;
}
@ -489,8 +485,6 @@ _finish_open (notmuch_database_t *notmuch,
} catch (const Xapian::Error &error) {
IGNORE_RESULT (asprintf (&message, "A Xapian exception occurred opening database: %s\n",
error.get_msg ().c_str ()));
notmuch_database_destroy (notmuch);
notmuch = NULL;
status = NOTMUCH_STATUS_XAPIAN_EXCEPTION;
}
DONE:
@ -559,10 +553,13 @@ notmuch_database_open_with_config (const char *database_path,
free (message);
}
if (status && notmuch) {
notmuch_database_destroy (notmuch);
notmuch = NULL;
}
if (database)
*database = notmuch;
else
talloc_free (notmuch);
if (notmuch)
notmuch->open = true;

View file

@ -862,7 +862,6 @@ cat <<EOF > c_tail3
EOF
test_begin_subtest "open: database set to null on missing config"
test_subtest_known_broken
cat c_head3 - c_tail3 <<'EOF' | test_C ${MAIL_DIR}
notmuch_status_t st = notmuch_database_open_with_config(argv[1],
NOTMUCH_DATABASE_MODE_READ_ONLY,
@ -876,7 +875,6 @@ EOF
test_expect_equal_file EXPECTED OUTPUT
test_begin_subtest "open: database set to null on missing config (env)"
test_subtest_known_broken
old_NOTMUCH_CONFIG=${NOTMUCH_CONFIG}
NOTMUCH_CONFIG="/nonexistent"
cat c_head3 - c_tail3 <<'EOF' | test_C ${MAIL_DIR}