Merge tag 'lsm-pr-20240312' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm

Pull lsm updates from Paul Moore:

 - Promote IMA/EVM to a proper LSM

   This is the bulk of the diffstat, and the source of all the changes
   in the VFS code. Prior to the start of the LSM stacking work it was
   important that IMA/EVM were separate from the rest of the LSMs,
   complete with their own hooks, infrastructure, etc. as it was the
   only way to enable IMA/EVM at the same time as a LSM.

   However, now that the bulk of the LSM infrastructure supports
   multiple simultaneous LSMs, we can simplify things greatly by
   bringing IMA/EVM into the LSM infrastructure as proper LSMs. This is
   something I've wanted to see happen for quite some time and Roberto
   was kind enough to put in the work to make it happen.

 - Use the LSM hook default values to simplify the call_int_hook() macro

   Previously the call_int_hook() macro required callers to supply a
   default return value, despite a default value being specified when
   the LSM hook was defined.

   This simplifies the macro by using the defined default return value
   which makes life easier for callers and should also reduce the number
   of return value bugs in the future (we've had a few pop up recently,
   hence this work).

 - Use the KMEM_CACHE() macro instead of kmem_cache_create()

   The guidance appears to be to use the KMEM_CACHE() macro when
   possible and there is no reason why we can't use the macro, so let's
   use it.

 - Fix a number of comment typos in the LSM hook comment blocks

   Not much to say here, we fixed some questionable grammar decisions in
   the LSM hook comment blocks.

* tag 'lsm-pr-20240312' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: (28 commits)
  cred: Use KMEM_CACHE() instead of kmem_cache_create()
  lsm: use default hook return value in call_int_hook()
  lsm: fix typos in security/security.c comment headers
  integrity: Remove LSM
  ima: Make it independent from 'integrity' LSM
  evm: Make it independent from 'integrity' LSM
  evm: Move to LSM infrastructure
  ima: Move IMA-Appraisal to LSM infrastructure
  ima: Move to LSM infrastructure
  integrity: Move integrity_kernel_module_request() to IMA
  security: Introduce key_post_create_or_update hook
  security: Introduce inode_post_remove_acl hook
  security: Introduce inode_post_set_acl hook
  security: Introduce inode_post_create_tmpfile hook
  security: Introduce path_post_mknod hook
  security: Introduce file_release hook
  security: Introduce file_post_open hook
  security: Introduce inode_post_removexattr hook
  security: Introduce inode_post_setattr hook
  security: Align inode_setattr hook definition with EVM
  ...

1 files changed, 43 insertions, 23 deletions

diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 870dde67707b..3497741caea9 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -84,8 +84,7 @@ int ima_must_appraise(struct mnt_idmap *idmap, struct inode *inode,
 				NULL, NULL, NULL);
 }
 
-static int ima_fix_xattr(struct dentry *dentry,
-			 struct integrity_iint_cache *iint)
+static int ima_fix_xattr(struct dentry *dentry, struct ima_iint_cache *iint)
 {
 	int rc, offset;
 	u8 algo = iint->ima_hash->algo;
@@ -106,7 +105,7 @@ static int ima_fix_xattr(struct dentry *dentry,
 }
 
 /* Return specific func appraised cached result */
-enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
+enum integrity_status ima_get_cache_status(struct ima_iint_cache *iint,
 					   enum ima_hooks func)
 {
 	switch (func) {
@@ -126,7 +125,7 @@ enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
 	}
 }
 
-static void ima_set_cache_status(struct integrity_iint_cache *iint,
+static void ima_set_cache_status(struct ima_iint_cache *iint,
 				 enum ima_hooks func,
 				 enum integrity_status status)
 {
@@ -152,8 +151,7 @@ static void ima_set_cache_status(struct integrity_iint_cache *iint,
 	}
 }
 
-static void ima_cache_flags(struct integrity_iint_cache *iint,
-			     enum ima_hooks func)
+static void ima_cache_flags(struct ima_iint_cache *iint, enum ima_hooks func)
 {
 	switch (func) {
 	case MMAP_CHECK:
@@ -276,7 +274,7 @@ static int calc_file_id_hash(enum evm_ima_xattr_type type,
  *
  * Return 0 on success, error code otherwise.
  */
-static int xattr_verify(enum ima_hooks func, struct integrity_iint_cache *iint,
+static int xattr_verify(enum ima_hooks func, struct ima_iint_cache *iint,
 			struct evm_ima_xattr_data *xattr_value, int xattr_len,
 			enum integrity_status *status, const char **cause)
 {
@@ -443,7 +441,7 @@ static int modsig_verify(enum ima_hooks func, const struct modsig *modsig,
  *
  * Returns -EPERM if the hash is blacklisted.
  */
-int ima_check_blacklist(struct integrity_iint_cache *iint,
+int ima_check_blacklist(struct ima_iint_cache *iint,
 			const struct modsig *modsig, int pcr)
 {
 	enum hash_algo hash_algo;
@@ -477,8 +475,7 @@ int ima_check_blacklist(struct integrity_iint_cache *iint,
  *
  * Return 0 on success, error code otherwise
  */
-int ima_appraise_measurement(enum ima_hooks func,
-			     struct integrity_iint_cache *iint,
+int ima_appraise_measurement(enum ima_hooks func, struct ima_iint_cache *iint,
 			     struct file *file, const unsigned char *filename,
 			     struct evm_ima_xattr_data *xattr_value,
 			     int xattr_len, const struct modsig *modsig)
@@ -520,7 +517,7 @@ int ima_appraise_measurement(enum ima_hooks func,
 	}
 
 	status = evm_verifyxattr(dentry, XATTR_NAME_IMA, xattr_value,
-				 rc < 0 ? 0 : rc, iint);
+				 rc < 0 ? 0 : rc);
 	switch (status) {
 	case INTEGRITY_PASS:
 	case INTEGRITY_PASS_IMMUTABLE:
@@ -603,7 +600,7 @@ out:
 /*
  * ima_update_xattr - update 'security.ima' hash value
  */
-void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
+void ima_update_xattr(struct ima_iint_cache *iint, struct file *file)
 {
 	struct dentry *dentry = file_dentry(file);
 	int rc = 0;
@@ -629,17 +626,18 @@ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
  * ima_inode_post_setattr - reflect file metadata changes
  * @idmap:  idmap of the mount the inode was found from
  * @dentry: pointer to the affected dentry
+ * @ia_valid: for the UID and GID status
  *
  * Changes to a dentry's metadata might result in needing to appraise.
  *
  * This function is called from notify_change(), which expects the caller
  * to lock the inode's i_mutex.
  */
-void ima_inode_post_setattr(struct mnt_idmap *idmap,
-			    struct dentry *dentry)
+static void ima_inode_post_setattr(struct mnt_idmap *idmap,
+				   struct dentry *dentry, int ia_valid)
 {
 	struct inode *inode = d_backing_inode(dentry);
-	struct integrity_iint_cache *iint;
+	struct ima_iint_cache *iint;
 	int action;
 
 	if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode)
@@ -647,7 +645,7 @@ void ima_inode_post_setattr(struct mnt_idmap *idmap,
 		return;
 
 	action = ima_must_appraise(idmap, inode, MAY_ACCESS, POST_SETATTR);
-	iint = integrity_iint_find(inode);
+	iint = ima_iint_find(inode);
 	if (iint) {
 		set_bit(IMA_CHANGE_ATTR, &iint->atomic_flags);
 		if (!action)
@@ -673,12 +671,12 @@ static int ima_protect_xattr(struct dentry *dentry, const char *xattr_name,
 
 static void ima_reset_appraise_flags(struct inode *inode, int digsig)
 {
-	struct integrity_iint_cache *iint;
+	struct ima_iint_cache *iint;
 
 	if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode))
 		return;
 
-	iint = integrity_iint_find(inode);
+	iint = ima_iint_find(inode);
 	if (!iint)
 		return;
 	iint->measured_pcrs = 0;
@@ -749,8 +747,9 @@ static int validate_hash_algo(struct dentry *dentry,
 	return -EACCES;
 }
 
-int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
-		       const void *xattr_value, size_t xattr_value_len)
+static int ima_inode_setxattr(struct mnt_idmap *idmap, struct dentry *dentry,
+			      const char *xattr_name, const void *xattr_value,
+			      size_t xattr_value_len, int flags)
 {
 	const struct evm_ima_xattr_data *xvalue = xattr_value;
 	int digsig = 0;
@@ -779,8 +778,8 @@ int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
 	return result;
 }
 
-int ima_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
-		      const char *acl_name, struct posix_acl *kacl)
+static int ima_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
+			     const char *acl_name, struct posix_acl *kacl)
 {
 	if (evm_revalidate_status(acl_name))
 		ima_reset_appraise_flags(d_backing_inode(dentry), 0);
@@ -788,7 +787,8 @@ int ima_inode_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
 	return 0;
 }
 
-int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name)
+static int ima_inode_removexattr(struct mnt_idmap *idmap, struct dentry *dentry,
+				 const char *xattr_name)
 {
 	int result;
 
@@ -800,3 +800,23 @@ int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name)
 	}
 	return result;
 }
+
+static int ima_inode_remove_acl(struct mnt_idmap *idmap, struct dentry *dentry,
+				const char *acl_name)
+{
+	return ima_inode_set_acl(idmap, dentry, acl_name, NULL);
+}
+
+static struct security_hook_list ima_appraise_hooks[] __ro_after_init = {
+	LSM_HOOK_INIT(inode_post_setattr, ima_inode_post_setattr),
+	LSM_HOOK_INIT(inode_setxattr, ima_inode_setxattr),
+	LSM_HOOK_INIT(inode_set_acl, ima_inode_set_acl),
+	LSM_HOOK_INIT(inode_removexattr, ima_inode_removexattr),
+	LSM_HOOK_INIT(inode_remove_acl, ima_inode_remove_acl),
+};
+
+void __init init_ima_appraise_lsm(const struct lsm_id *lsmid)
+{
+	security_add_hooks(ima_appraise_hooks, ARRAY_SIZE(ima_appraise_hooks),
+			   lsmid);
+}