From eb18219493485bff565141fd6ca581bebfaf7b77 Mon Sep 17 00:00:00 2001 From: Casey Schaufler Date: Mon, 17 Aug 2020 17:15:27 -0700 Subject: [PATCH] UBUNTU: SAUCE: LSM: Use lsmblob in security_audit_rule_match Change the secid parameter of security_audit_rule_match to a lsmblob structure pointer. Pass the entry from the lsmblob structure for the approprite slot to the LSM hook. Change the users of security_audit_rule_match to use the lsmblob instead of a u32. The scaffolding function lsmblob_init() fills the blob with the value of the old secid, ensuring that it is available to the appropriate module hook. The sources of the secid, security_task_getsecid() and security_inode_getsecid(), will be converted to use the blob structure later in the series. At the point the use of lsmblob_init() is dropped. Reviewed-by: Kees Cook Reviewed-by: John Johansen Acked-by: Stephen Smalley Signed-off-by: Casey Schaufler Signed-off-by: John Johansen Acked-by: Andrea Righi [ saf: resolve conflicts ] Signed-off-by: Seth Forshee --- include/linux/security.h | 7 ++++--- kernel/auditfilter.c | 6 ++++-- kernel/auditsc.c | 14 ++++++++++---- security/integrity/ima/ima.h | 2 +- security/integrity/ima/ima_policy.c | 7 +++++-- security/security.c | 10 ++++++++-- 6 files changed, 32 insertions(+), 14 deletions(-) diff --git a/include/linux/security.h b/include/linux/security.h index 50f0328989d3..00267626df9c 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -1941,7 +1941,8 @@ static inline int security_key_getsecurity(struct key *key, char **_buffer) #ifdef CONFIG_SECURITY int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule); int security_audit_rule_known(struct audit_krule *krule); -int security_audit_rule_match(u32 secid, u32 field, u32 op, void **lsmrule); +int security_audit_rule_match(struct lsmblob *blob, u32 field, u32 op, + void **lsmrule); void security_audit_rule_free(void **lsmrule); #else @@ -1957,8 +1958,8 @@ static inline int security_audit_rule_known(struct audit_krule *krule) return 0; } -static inline int security_audit_rule_match(u32 secid, u32 field, u32 op, - void **lsmrule) +static inline int security_audit_rule_match(struct lsmblob *blob, u32 field, + u32 op, void **lsmrule) { return 0; } diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index a2340e81cfa7..6a04d762d272 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -1331,6 +1331,7 @@ int audit_filter(int msgtype, unsigned int listtype) struct audit_field *f = &e->rule.fields[i]; pid_t pid; u32 sid; + struct lsmblob blob; switch (f->type) { case AUDIT_PID: @@ -1362,8 +1363,9 @@ int audit_filter(int msgtype, unsigned int listtype) if (f->lsm_isset) { security_task_getsecid_subj(current, &sid); - result = security_audit_rule_match(sid, - f->type, f->op, + lsmblob_init(&blob, sid); + result = security_audit_rule_match( + &blob, f->type, f->op, f->lsm_rules); } break; diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 3e2c2e3747a3..1f9056f17dee 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -478,6 +478,7 @@ static int audit_filter_rules(struct task_struct *tsk, const struct cred *cred; int i, need_sid = 1; u32 sid; + struct lsmblob blob; unsigned int sessionid; cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation); @@ -676,7 +677,9 @@ static int audit_filter_rules(struct task_struct *tsk, security_task_getsecid_subj(tsk, &sid); need_sid = 0; } - result = security_audit_rule_match(sid, f->type, + lsmblob_init(&blob, sid); + result = security_audit_rule_match(&blob, + f->type, f->op, f->lsm_rules); } @@ -691,15 +694,17 @@ static int audit_filter_rules(struct task_struct *tsk, if (f->lsm_isset) { /* Find files that match */ if (name) { + lsmblob_init(&blob, name->osid); result = security_audit_rule_match( - name->osid, + &blob, f->type, f->op, f->lsm_rules); } else if (ctx) { list_for_each_entry(n, &ctx->names_list, list) { + lsmblob_init(&blob, name->osid); if (security_audit_rule_match( - n->osid, + &blob, f->type, f->op, f->lsm_rules)) { @@ -711,7 +716,8 @@ static int audit_filter_rules(struct task_struct *tsk, /* Find ipc objects that match */ if (!ctx || ctx->type != AUDIT_IPC) break; - if (security_audit_rule_match(ctx->ipc.osid, + lsmblob_init(&blob, ctx->ipc.osid); + if (security_audit_rule_match(&blob, f->type, f->op, f->lsm_rules)) ++result; diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index be965a8715e4..6c2e35375dc8 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -437,7 +437,7 @@ static inline void ima_filter_rule_free(void *lsmrule) { } -static inline int ima_filter_rule_match(u32 secid, u32 field, u32 op, +static inline int ima_filter_rule_match(strcut lsmblob *blob, u32 field, u32 op, void *lsmrule) { return -EINVAL; diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index d85f2cf48e2c..918ac2959dfa 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -607,6 +607,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule, for (i = 0; i < MAX_LSM_RULES; i++) { int rc = 0; u32 osid; + struct lsmblob lsmdata; if (!ima_lsm_isset(rule->lsm[i].rules)) { if (!rule->lsm[i].args_p) @@ -619,14 +620,16 @@ static bool ima_match_rules(struct ima_rule_entry *rule, case LSM_OBJ_ROLE: case LSM_OBJ_TYPE: security_inode_getsecid(inode, &osid); - rc = ima_filter_rule_match(osid, rule->lsm[i].type, + lsmblob_init(&lsmdata, osid); + rc = ima_filter_rule_match(&lsmdata, rule->lsm[i].type, Audit_equal, rule->lsm[i].rules); break; case LSM_SUBJ_USER: case LSM_SUBJ_ROLE: case LSM_SUBJ_TYPE: - rc = ima_filter_rule_match(secid, rule->lsm[i].type, + lsmblob_init(&lsmdata, secid); + rc = ima_filter_rule_match(&lsmdata, rule->lsm[i].type, Audit_equal, rule->lsm[i].rules); break; diff --git a/security/security.c b/security/security.c index de841cfe99bf..673dd6536ce7 100644 --- a/security/security.c +++ b/security/security.c @@ -2629,11 +2629,14 @@ void security_audit_rule_free(void **lsmrule) hlist_for_each_entry(hp, &security_hook_heads.audit_rule_free, list) { if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) continue; + if (lsmrule[hp->lsmid->slot] == NULL) + continue; hp->hook.audit_rule_free(lsmrule[hp->lsmid->slot]); } } -int security_audit_rule_match(u32 secid, u32 field, u32 op, void **lsmrule) +int security_audit_rule_match(struct lsmblob *blob, u32 field, u32 op, + void **lsmrule) { struct security_hook_list *hp; int rc; @@ -2641,7 +2644,10 @@ int security_audit_rule_match(u32 secid, u32 field, u32 op, void **lsmrule) hlist_for_each_entry(hp, &security_hook_heads.audit_rule_match, list) { if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot)) continue; - rc = hp->hook.audit_rule_match(secid, field, op, + if (lsmrule[hp->lsmid->slot] == NULL) + continue; + rc = hp->hook.audit_rule_match(blob->secid[hp->lsmid->slot], + field, op, &lsmrule[hp->lsmid->slot]); if (rc) return rc; -- 2.39.5