diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c index 2f84bd23edb6..81e57666a56e 100644 --- a/security/apparmor/apparmorfs.c +++ b/security/apparmor/apparmorfs.c @@ -417,7 +417,8 @@ static struct aa_loaddata *aa_simple_write_to_buffer(const char __user *userbuf, } static ssize_t policy_update(u32 mask, const char __user *buf, size_t size, - loff_t *pos, struct aa_ns *ns) + loff_t *pos, struct aa_ns *ns, + const struct cred *ocred) { struct aa_loaddata *data; struct aa_label *label; @@ -428,7 +429,7 @@ static ssize_t policy_update(u32 mask, const char __user *buf, size_t size, /* high level check about policy management - fine grained in * below after unpack */ - error = aa_may_manage_policy(current_cred(), label, ns, mask); + error = aa_may_manage_policy(current_cred(), label, ns, ocred, mask); if (error) goto end_section; @@ -449,7 +450,8 @@ static ssize_t profile_load(struct file *f, const char __user *buf, size_t size, loff_t *pos) { struct aa_ns *ns = aa_get_ns(f->f_inode->i_private); - int error = policy_update(AA_MAY_LOAD_POLICY, buf, size, pos, ns); + int error = policy_update(AA_MAY_LOAD_POLICY, buf, size, pos, ns, + f->f_cred); aa_put_ns(ns); @@ -467,7 +469,7 @@ static ssize_t profile_replace(struct file *f, const char __user *buf, { struct aa_ns *ns = aa_get_ns(f->f_inode->i_private); int error = policy_update(AA_MAY_LOAD_POLICY | AA_MAY_REPLACE_POLICY, - buf, size, pos, ns); + buf, size, pos, ns, f->f_cred); aa_put_ns(ns); return error; @@ -492,7 +494,7 @@ static ssize_t profile_remove(struct file *f, const char __user *buf, * below after unpack */ error = aa_may_manage_policy(current_cred(), label, ns, - AA_MAY_REMOVE_POLICY); + f->f_cred, AA_MAY_REMOVE_POLICY); if (error) goto out; @@ -1830,7 +1832,7 @@ static struct dentry *ns_mkdir_op(struct mnt_idmap *idmap, struct inode *dir, int error; label = begin_current_label_crit_section(); - error = aa_may_manage_policy(current_cred(), label, NULL, + error = aa_may_manage_policy(current_cred(), label, NULL, NULL, AA_MAY_LOAD_POLICY); end_current_label_crit_section(label); if (error) @@ -1880,7 +1882,7 @@ static int ns_rmdir_op(struct inode *dir, struct dentry *dentry) int error; label = begin_current_label_crit_section(); - error = aa_may_manage_policy(current_cred(), label, NULL, + error = aa_may_manage_policy(current_cred(), label, NULL, NULL, AA_MAY_LOAD_POLICY); end_current_label_crit_section(label); if (error) diff --git a/security/apparmor/include/policy.h b/security/apparmor/include/policy.h index 5115ebae2661..fda9e75b8879 100644 --- a/security/apparmor/include/policy.h +++ b/security/apparmor/include/policy.h @@ -443,7 +443,7 @@ bool aa_policy_admin_capable(const struct cred *subj_cred, struct aa_label *label, struct aa_ns *ns); int aa_may_manage_policy(const struct cred *subj_cred, struct aa_label *label, struct aa_ns *ns, - u32 mask); + const struct cred *ocred, u32 mask); bool aa_current_policy_view_capable(struct aa_ns *ns); bool aa_current_policy_admin_capable(struct aa_ns *ns); diff --git a/security/apparmor/policy.c b/security/apparmor/policy.c index 4476515d97b1..e2bebf14a4d0 100644 --- a/security/apparmor/policy.c +++ b/security/apparmor/policy.c @@ -942,17 +942,44 @@ bool aa_current_policy_admin_capable(struct aa_ns *ns) return res; } +static bool is_subset_of_obj_privilege(const struct cred *cred, + struct aa_label *label, + const struct cred *ocred) +{ + if (cred == ocred) + return true; + + if (!aa_label_is_subset(label, cred_label(ocred))) + return false; + /* don't allow crossing userns for now */ + if (cred->user_ns != ocred->user_ns) + return false; + if (!cap_issubset(cred->cap_inheritable, ocred->cap_inheritable)) + return false; + if (!cap_issubset(cred->cap_permitted, ocred->cap_permitted)) + return false; + if (!cap_issubset(cred->cap_effective, ocred->cap_effective)) + return false; + if (!cap_issubset(cred->cap_bset, ocred->cap_bset)) + return false; + if (!cap_issubset(cred->cap_ambient, ocred->cap_ambient)) + return false; + return true; +} + + /** * aa_may_manage_policy - can the current task manage policy * @subj_cred: subjects cred * @label: label to check if it can manage policy * @ns: namespace being managed by @label (may be NULL if @label's ns) + * @ocred: object cred if request is coming from an open object * @mask: contains the policy manipulation operation being done * * Returns: 0 if the task is allowed to manipulate policy else error */ int aa_may_manage_policy(const struct cred *subj_cred, struct aa_label *label, - struct aa_ns *ns, u32 mask) + struct aa_ns *ns, const struct cred *ocred, u32 mask) { const char *op; @@ -968,6 +995,11 @@ int aa_may_manage_policy(const struct cred *subj_cred, struct aa_label *label, return audit_policy(label, op, NULL, NULL, "policy_locked", -EACCES); + if (ocred && !is_subset_of_obj_privilege(subj_cred, label, ocred)) + return audit_policy(label, op, NULL, NULL, + "not privileged for target profile", + -EACCES); + if (!aa_policy_admin_capable(subj_cred, label, ns)) return audit_policy(label, op, NULL, NULL, "not policy admin", -EACCES);