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apparmor: audit policy ns specified in policy load
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Verify that profiles in a load set specify the same policy ns and
audit the name of the policy ns that policy is being loaded for.

Signed-off-by: John Johansen <john.johansen@canonical.com>
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John Johansen committed Jan 16, 2017
1 parent 5ac8c35 commit 04dc715
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Showing 3 changed files with 77 additions and 24 deletions.
1 change: 1 addition & 0 deletions security/apparmor/include/policy_unpack.h
Original file line number Diff line number Diff line change
Expand Up @@ -23,6 +23,7 @@ struct aa_load_ent {
struct aa_profile *new;
struct aa_profile *old;
struct aa_profile *rename;
const char *ns_name;
};

void aa_load_ent_free(struct aa_load_ent *ent);
Expand Down
54 changes: 40 additions & 14 deletions security/apparmor/policy.c
Original file line number Diff line number Diff line change
Expand Up @@ -819,22 +819,48 @@ ssize_t aa_replace_profiles(struct aa_ns *view, bool noreplace,
struct aa_ns *ns = NULL;
struct aa_load_ent *ent, *tmp;
int op = OP_PROF_REPL;
ssize_t error;
ssize_t count, error;
LIST_HEAD(lh);

/* released below */
error = aa_unpack(udata, &lh, &ns_name);
if (error)
goto out;

/* released below */
ns = aa_prepare_ns(view, ns_name);
if (!ns) {
error = audit_policy(__aa_current_profile(), op, GFP_KERNEL,
NULL, ns_name,
"failed to prepare namespace", -ENOMEM);
goto free;
/* ensure that profiles are all for the same ns
* TODO: update locking to remove this constaint. All profiles in
* the load set must succeed as a set or the load will
* fail. Sort ent list and take ns locks in hierarchy order
*/
count = 0;
list_for_each_entry(ent, &lh, list) {
if (ns_name) {
if (ent->ns_name &&
strcmp(ent->ns_name, ns_name) != 0) {
info = "policy load has mixed namespaces";
error = -EACCES;
goto fail;
}
} else if (ent->ns_name) {
if (count) {
info = "policy load has mixed namespaces";
error = -EACCES;
goto fail;
}
ns_name = ent->ns_name;
} else
count++;
}
if (ns_name) {
ns = aa_prepare_ns(view, ns_name);
if (IS_ERR(ns)) {
info = "failed to prepare namespace";
error = PTR_ERR(ns);
ns = NULL;
goto fail;
}
} else
ns = aa_get_ns(view);

mutex_lock(&ns->lock);
/* setup parent and ns info */
Expand Down Expand Up @@ -964,7 +990,8 @@ ssize_t aa_replace_profiles(struct aa_ns *view, bool noreplace,

/* audit cause of failure */
op = (!ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
audit_policy(__aa_current_profile(), op, GFP_KERNEL, NULL,
fail:
audit_policy(__aa_current_profile(), op, GFP_KERNEL, ns_name,
ent->new->base.hname, info, error);
/* audit status that rest of profiles in the atomic set failed too */
info = "valid profile in failed atomic policy load";
Expand All @@ -975,10 +1002,9 @@ ssize_t aa_replace_profiles(struct aa_ns *view, bool noreplace,
continue;
}
op = (!ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
audit_policy(__aa_current_profile(), op, GFP_KERNEL, NULL,
audit_policy(__aa_current_profile(), op, GFP_KERNEL, ns_name,
tmp->new->base.hname, info, error);
}
free:
list_for_each_entry_safe(ent, tmp, &lh, list) {
list_del_init(&ent->list);
aa_load_ent_free(ent);
Expand All @@ -1005,6 +1031,7 @@ ssize_t aa_remove_profiles(struct aa_ns *view, char *fqname, size_t size)
struct aa_ns *root = NULL, *ns = NULL;
struct aa_profile *profile = NULL;
const char *name = fqname, *info = NULL;
char *ns_name = NULL;
ssize_t error = 0;

if (*fqname == 0) {
Expand All @@ -1016,7 +1043,6 @@ ssize_t aa_remove_profiles(struct aa_ns *view, char *fqname, size_t size)
root = view;

if (fqname[0] == ':') {
char *ns_name;
name = aa_split_fqname(fqname, &ns_name);
/* released below */
ns = aa_find_ns(root, ns_name);
Expand Down Expand Up @@ -1050,7 +1076,7 @@ ssize_t aa_remove_profiles(struct aa_ns *view, char *fqname, size_t size)

/* don't fail removal if audit fails */
(void) audit_policy(__aa_current_profile(), OP_PROF_RM, GFP_KERNEL,
NULL, name, info, error);
ns_name, name, info, error);
aa_put_ns(ns);
aa_put_profile(profile);
return size;
Expand All @@ -1061,6 +1087,6 @@ ssize_t aa_remove_profiles(struct aa_ns *view, char *fqname, size_t size)

fail:
(void) audit_policy(__aa_current_profile(), OP_PROF_RM, GFP_KERNEL,
NULL, name, info, error);
ns_name, name, info, error);
return error;
}
46 changes: 36 additions & 10 deletions security/apparmor/policy_unpack.c
Original file line number Diff line number Diff line change
Expand Up @@ -91,21 +91,24 @@ static void audit_cb(struct audit_buffer *ab, void *va)
/**
* audit_iface - do audit message for policy unpacking/load/replace/remove
* @new: profile if it has been allocated (MAYBE NULL)
* @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL)
* @name: name of the profile being manipulated (MAYBE NULL)
* @info: any extra info about the failure (MAYBE NULL)
* @e: buffer position info
* @error: error code
*
* Returns: %0 or error
*/
static int audit_iface(struct aa_profile *new, const char *name,
const char *info, struct aa_ext *e, int error)
static int audit_iface(struct aa_profile *new, const char *ns_name,
const char *name, const char *info, struct aa_ext *e,
int error)
{
struct aa_profile *profile = __aa_current_profile();
struct common_audit_data sa;
struct apparmor_audit_data aad = {0,};
sa.type = LSM_AUDIT_DATA_NONE;
sa.aad = &aad;
aad.iface.ns = ns_name;
if (e)
aad.iface.pos = e->pos - e->start;
aad.iface.target = new;
Expand Down Expand Up @@ -486,19 +489,32 @@ static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
*
* NOTE: unpack profile sets audit struct if there is a failure
*/
static struct aa_profile *unpack_profile(struct aa_ext *e)
static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
{
struct aa_profile *profile = NULL;
const char *name = NULL;
const char *tmpname, *tmpns = NULL, *name = NULL;
size_t ns_len;
int i, error = -EPROTO;
kernel_cap_t tmpcap;
u32 tmp;

*ns_name = NULL;

/* check that we have the right struct being passed */
if (!unpack_nameX(e, AA_STRUCT, "profile"))
goto fail;
if (!unpack_str(e, &name, NULL))
goto fail;
if (*name == '\0')
goto fail;

tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
if (tmpns) {
*ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
if (!*ns_name)
goto fail;
name = tmpname;
}

profile = aa_alloc_profile(name, GFP_KERNEL);
if (!profile)
Expand Down Expand Up @@ -646,7 +662,8 @@ static struct aa_profile *unpack_profile(struct aa_ext *e)
name = NULL;
else if (!name)
name = "unknown";
audit_iface(profile, name, "failed to unpack profile", e, error);
audit_iface(profile, NULL, name, "failed to unpack profile", e,
error);
aa_free_profile(profile);

return ERR_PTR(error);
Expand All @@ -669,7 +686,7 @@ static int verify_header(struct aa_ext *e, int required, const char **ns)
/* get the interface version */
if (!unpack_u32(e, &e->version, "version")) {
if (required) {
audit_iface(NULL, NULL, "invalid profile format",
audit_iface(NULL, NULL, NULL, "invalid profile format",
e, error);
return error;
}
Expand All @@ -680,15 +697,21 @@ static int verify_header(struct aa_ext *e, int required, const char **ns)
* Mask off everything that is not kernel abi version
*/
if (VERSION_LT(e->version, v5) && VERSION_GT(e->version, v7)) {
audit_iface(NULL, NULL, "unsupported interface version",
audit_iface(NULL, NULL, NULL, "unsupported interface version",
e, error);
return error;
}

/* read the namespace if present */
if (unpack_str(e, &name, "namespace")) {
if (*name == '\0') {
audit_iface(NULL, NULL, NULL, "invalid namespace name",
e, error);
return error;
}
if (*ns && strcmp(*ns, name))
audit_iface(NULL, NULL, "invalid ns change", e, error);
audit_iface(NULL, NULL, NULL, "invalid ns change", e,
error);
else if (!*ns)
*ns = name;
}
Expand Down Expand Up @@ -730,7 +753,7 @@ static int verify_profile(struct aa_profile *profile)
if (profile->file.dfa &&
!verify_dfa_xindex(profile->file.dfa,
profile->file.trans.size)) {
audit_iface(profile, NULL, "Invalid named transition",
audit_iface(profile, NULL, NULL, "Invalid named transition",
NULL, -EPROTO);
return -EPROTO;
}
Expand All @@ -744,6 +767,7 @@ void aa_load_ent_free(struct aa_load_ent *ent)
aa_put_profile(ent->rename);
aa_put_profile(ent->old);
aa_put_profile(ent->new);
kfree(ent->ns_name);
kzfree(ent);
}
}
Expand Down Expand Up @@ -782,13 +806,14 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,

*ns = NULL;
while (e.pos < e.end) {
char *ns_name = NULL;
void *start;
error = verify_header(&e, e.pos == e.start, ns);
if (error)
goto fail;

start = e.pos;
profile = unpack_profile(&e);
profile = unpack_profile(&e, &ns_name);
if (IS_ERR(profile)) {
error = PTR_ERR(profile);
goto fail;
Expand All @@ -810,6 +835,7 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
}

ent->new = profile;
ent->ns_name = ns_name;
list_add_tail(&ent->list, lh);
}
udata->abi = e.version & K_ABI_MASK;
Expand Down

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