Merge tag 'apparmor-pr-2025-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor

Pull apparmor updates from John Johansen:
 "This has one major feature, it pulls in a cleaned up version of
  af_unix mediation that Ubuntu has been carrying for years. It is
  placed behind a new abi to ensure that it does cause policy
  regressions. With pulling in the af_unix mediation there have been
  cleanups and some refactoring of network socket mediation. This
  accounts for the majority of the changes in the diff.

  In addition there are a few improvements providing minor code
  optimizations. several code cleanups, and bug fixes.

  Features:
   - improve debug printing
   - carry mediation check on label (optimization)
   - improve ability for compiler to optimize
     __begin_current_label_crit_section
   - transition for a linked list of rulesets to a vector of rulesets
   - don't hardcode profile signal, allow it to be set by policy
   - ability to mediate caps via the state machine instead of lut
   - Add Ubuntu af_unix mediation, put it behind new v9 abi

  Cleanups:
   - fix typos and spelling errors
   - cleanup kernel doc and code inconsistencies
   - remove redundant checks/code
   - remove unused variables
   - Use str_yes_no() helper function
   - mark tables static where appropriate
   - make all generated string array headers const char *const
   - refactor to doc semantics of file_perm checks
   - replace macro calls to network/socket fns with explicit calls
   - refactor/cleanup socket mediation code preparing for finer grained
     mediation of different network families
   - several updates to kernel doc comments

  Bug fixes:
   - fix incorrect profile->signal range check
   - idmap mount fixes
   - policy unpack unaligned access fixes
   - kfree_sensitive() where appropriate
   - fix oops when freeing policy
   - fix conflicting attachment resolution
   - fix exec table look-ups when stacking isn't first
   - fix exec auditing
   - mitigate userspace generating overly large xtables"

* tag 'apparmor-pr-2025-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor: (60 commits)
  apparmor: fix: oops when trying to free null ruleset
  apparmor: fix Regression on linux-next (next-20250721)
  apparmor: fix test error: WARNING in apparmor_unix_stream_connect
  apparmor: Remove the unused variable rules
  apparmor: fix: accept2 being specifie even when permission table is presnt
  apparmor: transition from a list of rules to a vector of rules
  apparmor: fix documentation mismatches in val_mask_to_str and socket functions
  apparmor: remove redundant perms.allow MAY_EXEC bitflag set
  apparmor: fix kernel doc warnings for kernel test robot
  apparmor: Fix unaligned memory accesses in KUnit test
  apparmor: Fix 8-byte alignment for initial dfa blob streams
  apparmor: shift uid when mediating af_unix in userns
  apparmor: shift ouid when mediating hard links in userns
  apparmor: make sure unix socket labeling is correctly updated.
  apparmor: fix regression in fs based unix sockets when using old abi
  apparmor: fix AA_DEBUG_LABEL()
  apparmor: fix af_unix auditing to include all address information
  apparmor: Remove use of the double lock
  apparmor: update kernel doc comments for xxx_label_crit_section
  apparmor: make __begin_current_label_crit_section() indicate whether put is needed
  ...

1 files changed, 35 insertions, 16 deletions

diff --git a/security/apparmor/include/label.h b/security/apparmor/include/label.h
index 93290ae300bb..c0812dbc1b5b 100644
--- a/security/apparmor/include/label.h
+++ b/security/apparmor/include/label.h
@@ -19,6 +19,7 @@
 #include "lib.h"
 
 struct aa_ns;
+struct aa_ruleset;
 
 #define LOCAL_VEC_ENTRIES 8
 #define DEFINE_VEC(T, V)						\
@@ -109,7 +110,7 @@ struct label_it {
 	int i, j;
 };
 
-/* struct aa_label - lazy labeling struct
+/* struct aa_label_base - base info of label
  * @count: ref count of active users
  * @node: rbtree position
  * @rcu: rcu callback struct
@@ -118,7 +119,10 @@ struct label_it {
  * @flags: stale and other flags - values may change under label set lock
  * @secid: secid that references this label
  * @size: number of entries in @ent[]
- * @ent: set of profiles for label, actual size determined by @size
+ * @mediates: bitmask for label_mediates
+ * profile: label vec when embedded in a profile FLAG_PROFILE is set
+ * rules: variable length rules in a profile FLAG_PROFILE is set
+ * vec: vector of profiles comprising the compound label
  */
 struct aa_label {
 	struct kref count;
@@ -129,7 +133,18 @@ struct aa_label {
 	long flags;
 	u32 secid;
 	int size;
-	struct aa_profile *vec[];
+	u64 mediates;
+	union {
+		struct {
+			/* only used is the label is a profile, size of
+			 * rules[] is determined by the profile
+			 * profile[1] is poison or null as guard
+			 */
+			struct aa_profile *profile[2];
+			DECLARE_FLEX_ARRAY(struct aa_ruleset *, rules);
+		};
+		DECLARE_FLEX_ARRAY(struct aa_profile *, vec);
+	};
 };
 
 #define last_error(E, FN)				\
@@ -231,20 +246,17 @@ int aa_label_next_confined(struct aa_label *l, int i);
 #define fn_for_each_not_in_set(L1, L2, P, FN)				\
 	fn_for_each2_XXX((L1), (L2), P, FN, _not_in_set)
 
-#define LABEL_MEDIATES(L, C)						\
-({									\
-	struct aa_profile *profile;					\
-	struct label_it i;						\
-	int ret = 0;							\
-	label_for_each(i, (L), profile) {				\
-		if (RULE_MEDIATES(&profile->rules, (C))) {		\
-			ret = 1;					\
-			break;						\
-		}							\
-	}								\
-	ret;								\
-})
+static inline bool label_mediates(struct aa_label *L, unsigned char C)
+{
+	return (L)->mediates & (((u64) 1) << (C));
+}
 
+static inline bool label_mediates_safe(struct aa_label *L, unsigned char C)
+{
+	if (C > AA_CLASS_LAST)
+		return false;
+	return label_mediates(L, C);
+}
 
 void aa_labelset_destroy(struct aa_labelset *ls);
 void aa_labelset_init(struct aa_labelset *ls);
@@ -417,6 +429,13 @@ static inline void aa_put_label(struct aa_label *l)
 		kref_put(&l->count, aa_label_kref);
 }
 
+/* wrapper fn to indicate semantics of the check */
+static inline bool __aa_subj_label_is_cached(struct aa_label *subj_label,
+					  struct aa_label *obj_label)
+{
+	return aa_label_is_subset(obj_label, subj_label);
+}
+
 
 struct aa_proxy *aa_alloc_proxy(struct aa_label *l, gfp_t gfp);
 void aa_proxy_kref(struct kref *kref);