apparmor: name null-XXX profiles after the executable

When possible its better to name a learning profile after the missing
profile in question. This allows for both more informative names and
for profile reuse.

Signed-off-by: John Johansen <john.johansen@canonical.com>
This commit is contained in:
John Johansen 2017-01-16 00:42:36 -08:00
parent 30b026a8d1
commit 181f7c9776
3 changed files with 47 additions and 17 deletions

View File

@ -442,7 +442,8 @@ int apparmor_bprm_set_creds(struct linux_binprm *bprm)
}
} else if (COMPLAIN_MODE(profile)) {
/* no exec permission - are we in learning mode */
new_profile = aa_new_null_profile(profile, 0);
new_profile = aa_new_null_profile(profile, false, name,
GFP_ATOMIC);
if (!new_profile) {
error = -ENOMEM;
info = "could not create null profile";
@ -667,7 +668,8 @@ int aa_change_hat(const char *hats[], int count, u64 token, bool permtest)
aa_put_profile(root);
target = name;
/* released below */
hat = aa_new_null_profile(profile, 1);
hat = aa_new_null_profile(profile, true, hats[0],
GFP_KERNEL);
if (!hat) {
info = "failed null profile create";
error = -ENOMEM;
@ -815,7 +817,7 @@ int aa_change_profile(const char *ns_name, const char *hname, bool onexec,
if (permtest || !COMPLAIN_MODE(profile))
goto audit;
/* released below */
target = aa_new_null_profile(profile, 0);
target = aa_new_null_profile(profile, false, hname, GFP_KERNEL);
if (!target) {
info = "failed null profile create";
error = -ENOMEM;

View File

@ -173,7 +173,8 @@ void aa_add_profile(struct aa_policy *common, struct aa_profile *profile);
void aa_free_proxy_kref(struct kref *kref);
struct aa_profile *aa_alloc_profile(const char *name, gfp_t gfp);
struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat);
struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat,
const char *base, gfp_t gfp);
void aa_free_profile(struct aa_profile *profile);
void aa_free_profile_kref(struct kref *kref);
struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name);

View File

@ -288,12 +288,16 @@ fail:
}
/**
* aa_new_null_profile - create a new null-X learning profile
* aa_new_null_profile - create or find a null-X learning profile
* @parent: profile that caused this profile to be created (NOT NULL)
* @hat: true if the null- learning profile is a hat
* @base: name to base the null profile off of
* @gfp: type of allocation
*
* Create a null- complain mode profile used in learning mode. The name of
* the profile is unique and follows the format of parent//null-<uniq>.
* Find/Create a null- complain mode profile used in learning mode. The
* name of the profile is unique and follows the format of parent//null-XXX.
* where XXX is based on the @name or if that fails or is not supplied
* a unique number
*
* null profiles are added to the profile list but the list does not
* hold a count on them so that they are automatically released when
@ -301,27 +305,45 @@ fail:
*
* Returns: new refcounted profile else NULL on failure
*/
struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat)
struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat,
const char *base, gfp_t gfp)
{
struct aa_profile *profile = NULL;
struct aa_profile *profile;
char *name;
int uniq = atomic_inc_return(&parent->ns->uniq_null);
/* freed below */
name = kmalloc(strlen(parent->base.hname) + 2 + 7 + 8, GFP_KERNEL);
AA_BUG(!parent);
if (base) {
name = kmalloc(strlen(parent->base.hname) + 8 + strlen(base),
gfp);
if (name) {
sprintf(name, "%s//null-%s", parent->base.hname, base);
goto name;
}
/* fall through to try shorter uniq */
}
name = kmalloc(strlen(parent->base.hname) + 2 + 7 + 8, gfp);
if (!name)
goto fail;
sprintf(name, "%s//null-%x", parent->base.hname, uniq);
return NULL;
sprintf(name, "%s//null-%x", parent->base.hname,
atomic_inc_return(&parent->ns->uniq_null));
profile = aa_alloc_profile(name, GFP_KERNEL);
kfree(name);
name:
/* lookup to see if this is a dup creation */
profile = aa_find_child(parent, basename(name));
if (profile)
goto out;
profile = aa_alloc_profile(name, gfp);
if (!profile)
goto fail;
profile->mode = APPARMOR_COMPLAIN;
profile->flags = PFLAG_NULL;
profile->flags |= PFLAG_NULL;
if (hat)
profile->flags |= PFLAG_HAT;
profile->path_flags = parent->path_flags;
/* released on free_profile */
rcu_assign_pointer(profile->parent, aa_get_profile(parent));
@ -332,9 +354,14 @@ struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat)
mutex_unlock(&profile->ns->lock);
/* refcount released by caller */
out:
kfree(name);
return profile;
fail:
kfree(name);
aa_free_profile(profile);
return NULL;
}