[31309] in CVS-changelog-for-Kerberos-V5
krb5 commit: Allow modifications of empty profiles
daemon@ATHENA.MIT.EDU (ghudson@mit.edu)
Wed Apr 17 18:26:14 2024
From: ghudson@mit.edu
To: cvs-krb5@mit.edu
Message-Id: <20240417222607.0BE891019F1@krbdev.mit.edu>
Date: Wed, 17 Apr 2024 18:26:07 -0400 (EDT)
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https://github.com/krb5/krb5/commit/fc54edd1dc047aedb211beaa544c5e000fbdb7a6
commit fc54edd1dc047aedb211beaa544c5e000fbdb7a6
Author: Greg Hudson <ghudson@mit.edu>
Date: Sun Mar 31 12:30:18 2024 -0400
Allow modifications of empty profiles
Add the notion of a memory-only prf_data_t object, indicated by an
empty filespec field and appropriate flags (do not reload, always
dirty, not part of shared trees). Do nothing when flushing a
memory-only data object to its backing file. When setting up an empty
profile for read/write access, create a memory-only data object
instead of crashing.
Move prf_data_t mutex initialization into profile_make_prf_data(),
simplifying its callers.
ticket: 9110
src/util/profile/prof_file.c | 46 +++++++++++++++++++++++++++++++++++++-------
src/util/profile/prof_int.h | 2 ++
src/util/profile/prof_set.c | 33 ++++++++++++++-----------------
src/util/profile/t_profile.c | 28 +++++++++++++++++++++++++++
4 files changed, 83 insertions(+), 26 deletions(-)
diff --git a/src/util/profile/prof_file.c b/src/util/profile/prof_file.c
index aa951df05..b5eddc0d9 100644
--- a/src/util/profile/prof_file.c
+++ b/src/util/profile/prof_file.c
@@ -159,6 +159,10 @@ profile_make_prf_data(const char *filename)
d->root = NULL;
d->next = NULL;
d->fslen = flen;
+ if (k5_mutex_init(&d->lock) != 0) {
+ free(d);
+ return NULL;
+ }
return d;
}
@@ -239,13 +243,6 @@ errcode_t profile_open_file(const_profile_filespec_t filespec,
free(expanded_filename);
prf->data = data;
- retval = k5_mutex_init(&data->lock);
- if (retval) {
- free(data);
- free(prf);
- return retval;
- }
-
retval = profile_update_file(prf, ret_modspec);
if (retval) {
profile_close_file(prf);
@@ -262,6 +259,37 @@ errcode_t profile_open_file(const_profile_filespec_t filespec,
return 0;
}
+prf_file_t profile_open_memory(void)
+{
+ struct profile_node *root = NULL;
+ prf_file_t file = NULL;
+ prf_data_t data;
+
+ file = calloc(1, sizeof(*file));
+ if (file == NULL)
+ goto errout;
+ file->magic = PROF_MAGIC_FILE;
+
+ if (profile_create_node("(root)", NULL, &root) != 0)
+ goto errout;
+
+ data = profile_make_prf_data("");
+ if (data == NULL)
+ goto errout;
+
+ data->root = root;
+ data->flags = PROFILE_FILE_NO_RELOAD | PROFILE_FILE_DIRTY;
+ file->data = data;
+ file->next = NULL;
+ return file;
+
+errout:
+ free(file);
+ if (root != NULL)
+ profile_free_node(root);
+ return NULL;
+}
+
errcode_t profile_update_file_data_locked(prf_data_t data, char **ret_modspec)
{
errcode_t retval;
@@ -468,6 +496,10 @@ errcode_t profile_flush_file_data(prf_data_t data)
if (!data || data->magic != PROF_MAGIC_FILE_DATA)
return PROF_MAGIC_FILE_DATA;
+ /* Do nothing if this data object has no backing file. */
+ if (*data->filespec == '\0')
+ return 0;
+
k5_mutex_lock(&data->lock);
if ((data->flags & PROFILE_FILE_DIRTY) == 0) {
diff --git a/src/util/profile/prof_int.h b/src/util/profile/prof_int.h
index 1ee9a8ca1..21c535a5c 100644
--- a/src/util/profile/prof_int.h
+++ b/src/util/profile/prof_int.h
@@ -214,6 +214,8 @@ errcode_t profile_open_file
(const_profile_filespec_t file, prf_file_t *ret_prof,
char **ret_modspec);
+prf_file_t profile_open_memory(void);
+
#define profile_update_file(P, M) profile_update_file_data((P)->data, M)
errcode_t profile_update_file_data
(prf_data_t profile, char **ret_modspec);
diff --git a/src/util/profile/prof_set.c b/src/util/profile/prof_set.c
index af4b2f853..aeea676cb 100644
--- a/src/util/profile/prof_set.c
+++ b/src/util/profile/prof_set.c
@@ -24,7 +24,7 @@
static errcode_t rw_setup(profile_t profile)
{
prf_file_t file;
- errcode_t retval = 0;
+ prf_data_t new_data;
if (!profile)
return PROF_NO_PROFILE;
@@ -32,6 +32,12 @@ static errcode_t rw_setup(profile_t profile)
if (profile->magic != PROF_MAGIC_PROFILE)
return PROF_MAGIC_PROFILE;
+ /* If the profile has no files, create a memory-only data object. */
+ if (profile->first_file == NULL) {
+ profile->first_file = profile_open_memory();
+ return (profile->first_file == NULL) ? ENOMEM : 0;
+ }
+
file = profile->first_file;
profile_lock_global();
@@ -43,33 +49,22 @@ static errcode_t rw_setup(profile_t profile)
}
if ((file->data->flags & PROFILE_FILE_SHARED) != 0) {
- prf_data_t new_data;
new_data = profile_make_prf_data(file->data->filespec);
if (new_data == NULL) {
- retval = ENOMEM;
- } else {
- retval = k5_mutex_init(&new_data->lock);
- if (retval == 0) {
- new_data->root = NULL;
- new_data->flags = file->data->flags & ~PROFILE_FILE_SHARED;
- new_data->timestamp = 0;
- new_data->upd_serial = file->data->upd_serial;
- }
- }
-
- if (retval != 0) {
profile_unlock_global();
- free(new_data);
- return retval;
+ return ENOMEM;
}
+ new_data->root = NULL;
+ new_data->flags = file->data->flags & ~PROFILE_FILE_SHARED;
+ new_data->timestamp = 0;
+ new_data->upd_serial = file->data->upd_serial;
+
profile_dereference_data_locked(file->data);
file->data = new_data;
}
profile_unlock_global();
- retval = profile_update_file(file, NULL);
-
- return retval;
+ return profile_update_file(file, NULL);
}
diff --git a/src/util/profile/t_profile.c b/src/util/profile/t_profile.c
index bffd11561..0e859b97c 100644
--- a/src/util/profile/t_profile.c
+++ b/src/util/profile/t_profile.c
@@ -373,6 +373,33 @@ test_merge_subsections(void)
profile_release(p);
}
+/* Regression test for #9110 (null dereference when modifying an empty
+ * profile), and various other operations on an initially empty profile. */
+static void
+test_empty(void)
+{
+ profile_t p;
+ const char *n1[] = { "section", NULL };
+ const char *n2[] = { "section", "var", NULL };
+ char **values;
+
+ check(profile_init(NULL, &p));
+ check(profile_add_relation(p, n1, NULL));
+ check(profile_add_relation(p, n2, "value"));
+ check(profile_flush(p)); /* should succeed but do nothing */
+ check(profile_get_values(p, n2, &values));
+ assert(strcmp(values[0], "value") == 0 && values[1] == NULL);
+ profile_free_list(values);
+ profile_flush_to_file(p, "test3.ini");
+ profile_release(p);
+
+ profile_init_path("test3.ini", &p);
+ check(profile_get_values(p, n2, &values));
+ assert(strcmp(values[0], "value") == 0 && values[1] == NULL);
+ profile_free_list(values);
+ profile_release(p);
+}
+
int
main(void)
{
@@ -386,4 +413,5 @@ main(void)
test_delete_ordering();
test_flush_to_file();
test_merge_subsections();
+ test_empty();
}
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