@@ -12,15 +12,12 @@
#include <linux/integrity.h>
#include <linux/xattr.h>
-struct integrity_iint_cache;
-
#ifdef CONFIG_EVM
extern int evm_set_key(void *key, size_t keylen);
extern enum integrity_status evm_verifyxattr(struct dentry *dentry,
const char *xattr_name,
void *xattr_value,
- size_t xattr_value_len,
- struct integrity_iint_cache *iint);
+ size_t xattr_value_len);
int evm_inode_init_security(struct inode *inode, struct inode *dir,
const struct qstr *qstr, struct xattr *xattrs,
int *xattr_count);
@@ -48,8 +45,7 @@ static inline int evm_set_key(void *key, size_t keylen)
static inline enum integrity_status evm_verifyxattr(struct dentry *dentry,
const char *xattr_name,
void *xattr_value,
- size_t xattr_value_len,
- struct integrity_iint_cache *iint)
+ size_t xattr_value_len)
{
return INTEGRITY_UNKNOWN;
}
@@ -32,6 +32,25 @@ struct xattr_list {
bool enabled;
};
+#define EVM_NEW_FILE 0x00000001
+#define EVM_IMMUTABLE_DIGSIG 0x00000002
+
+/* EVM integrity metadata associated with an inode */
+struct evm_iint_cache {
+ unsigned long flags;
+ enum integrity_status evm_status:4;
+};
+
+extern struct lsm_blob_sizes evm_blob_sizes;
+
+static inline struct evm_iint_cache *evm_iint_inode(const struct inode *inode)
+{
+ if (unlikely(!inode->i_security))
+ return NULL;
+
+ return inode->i_security + evm_blob_sizes.lbs_inode;
+}
+
extern int evm_initialized;
#define EVM_ATTR_FSUUID 0x0001
@@ -322,10 +322,10 @@ int evm_calc_hash(struct dentry *dentry, const char *req_xattr_name,
static int evm_is_immutable(struct dentry *dentry, struct inode *inode)
{
const struct evm_ima_xattr_data *xattr_data = NULL;
- struct integrity_iint_cache *iint;
+ struct evm_iint_cache *iint;
int rc = 0;
- iint = integrity_iint_find(inode);
+ iint = evm_iint_inode(inode);
if (iint && (iint->flags & EVM_IMMUTABLE_DIGSIG))
return 1;
@@ -167,14 +167,14 @@ static int evm_find_protected_xattrs(struct dentry *dentry)
static enum integrity_status evm_verify_hmac(struct dentry *dentry,
const char *xattr_name,
char *xattr_value,
- size_t xattr_value_len,
- struct integrity_iint_cache *iint)
+ size_t xattr_value_len)
{
struct evm_ima_xattr_data *xattr_data = NULL;
struct signature_v2_hdr *hdr;
enum integrity_status evm_status = INTEGRITY_PASS;
struct evm_digest digest;
- struct inode *inode;
+ struct inode *inode = d_backing_inode(dentry);
+ struct evm_iint_cache *iint = evm_iint_inode(inode);
int rc, xattr_len, evm_immutable = 0;
if (iint && (iint->evm_status == INTEGRITY_PASS ||
@@ -240,8 +240,6 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry,
(const char *)xattr_data, xattr_len,
digest.digest, digest.hdr.length);
if (!rc) {
- inode = d_backing_inode(dentry);
-
if (xattr_data->type == EVM_XATTR_PORTABLE_DIGSIG) {
if (iint)
iint->flags |= EVM_IMMUTABLE_DIGSIG;
@@ -389,7 +387,6 @@ int evm_read_protected_xattrs(struct dentry *dentry, u8 *buffer,
* @xattr_name: requested xattr
* @xattr_value: requested xattr value
* @xattr_value_len: requested xattr value length
- * @iint: inode integrity metadata
*
* Calculate the HMAC for the given dentry and verify it against the stored
* security.evm xattr. For performance, use the xattr value and length
@@ -402,19 +399,13 @@ int evm_read_protected_xattrs(struct dentry *dentry, u8 *buffer,
*/
enum integrity_status evm_verifyxattr(struct dentry *dentry,
const char *xattr_name,
- void *xattr_value, size_t xattr_value_len,
- struct integrity_iint_cache *iint)
+ void *xattr_value, size_t xattr_value_len)
{
if (!evm_key_loaded() || !evm_protected_xattr(xattr_name))
return INTEGRITY_UNKNOWN;
- if (!iint) {
- iint = integrity_iint_find(d_backing_inode(dentry));
- if (!iint)
- return INTEGRITY_UNKNOWN;
- }
return evm_verify_hmac(dentry, xattr_name, xattr_value,
- xattr_value_len, iint);
+ xattr_value_len);
}
EXPORT_SYMBOL_GPL(evm_verifyxattr);
@@ -431,7 +422,7 @@ static enum integrity_status evm_verify_current_integrity(struct dentry *dentry)
if (!evm_key_loaded() || !S_ISREG(inode->i_mode) || evm_fixmode)
return INTEGRITY_PASS;
- return evm_verify_hmac(dentry, NULL, NULL, 0, NULL);
+ return evm_verify_hmac(dentry, NULL, NULL, 0);
}
/*
@@ -503,14 +494,14 @@ static int evm_protect_xattr(struct mnt_idmap *idmap,
evm_status = evm_verify_current_integrity(dentry);
if (evm_status == INTEGRITY_NOXATTRS) {
- struct integrity_iint_cache *iint;
+ struct evm_iint_cache *iint;
/* Exception if the HMAC is not going to be calculated. */
if (evm_hmac_disabled())
return 0;
- iint = integrity_iint_find(d_backing_inode(dentry));
- if (iint && (iint->flags & IMA_NEW_FILE))
+ iint = evm_iint_inode(d_backing_inode(dentry));
+ if (iint && (iint->flags & EVM_NEW_FILE))
return 0;
/* exception for pseudo filesystems */
@@ -712,9 +703,9 @@ static int evm_inode_remove_acl(struct mnt_idmap *idmap, struct dentry *dentry,
static void evm_reset_status(struct inode *inode)
{
- struct integrity_iint_cache *iint;
+ struct evm_iint_cache *iint;
- iint = integrity_iint_find(inode);
+ iint = evm_iint_inode(inode);
if (iint)
iint->evm_status = INTEGRITY_UNKNOWN;
}
@@ -979,6 +970,43 @@ int evm_inode_init_security(struct inode *inode, struct inode *dir,
}
EXPORT_SYMBOL_GPL(evm_inode_init_security);
+static int evm_inode_alloc_security(struct inode *inode)
+{
+ struct evm_iint_cache *iint = evm_iint_inode(inode);
+
+ /* Called by security_inode_alloc(), it cannot be NULL. */
+ iint->flags = 0UL;
+ iint->evm_status = INTEGRITY_UNKNOWN;
+
+ return 0;
+}
+
+static void evm_file_free(struct file *file)
+{
+ struct inode *inode = file_inode(file);
+ struct evm_iint_cache *iint = evm_iint_inode(inode);
+ fmode_t mode = file->f_mode;
+
+ if (!S_ISREG(inode->i_mode) || !(mode & FMODE_WRITE))
+ return;
+
+ if (iint && atomic_read(&inode->i_writecount) == 1)
+ iint->flags &= ~EVM_NEW_FILE;
+}
+
+static void __maybe_unused
+evm_post_path_mknod(struct mnt_idmap *idmap, struct dentry *dentry)
+{
+ struct inode *inode = d_backing_inode(dentry);
+ struct evm_iint_cache *iint = evm_iint_inode(inode);
+
+ if (!S_ISREG(inode->i_mode))
+ return;
+
+ if (iint)
+ iint->flags |= EVM_NEW_FILE;
+}
+
#ifdef CONFIG_EVM_LOAD_X509
void __init evm_load_x509(void)
{
@@ -1030,6 +1058,11 @@ static struct security_hook_list evm_hooks[] __ro_after_init = {
LSM_HOOK_INIT(inode_removexattr, evm_inode_removexattr),
LSM_HOOK_INIT(inode_post_removexattr, evm_inode_post_removexattr),
LSM_HOOK_INIT(inode_init_security, evm_inode_init_security),
+ LSM_HOOK_INIT(inode_alloc_security, evm_inode_alloc_security),
+ LSM_HOOK_INIT(file_release, evm_file_free),
+#ifdef CONFIG_SECURITY_PATH
+ LSM_HOOK_INIT(path_post_mknod, evm_post_path_mknod),
+#endif
};
static const struct lsm_id evm_lsmid = {
@@ -1043,10 +1076,16 @@ static int __init init_evm_lsm(void)
return 0;
}
+struct lsm_blob_sizes evm_blob_sizes __ro_after_init = {
+ .lbs_inode = sizeof(struct evm_iint_cache),
+ .lbs_xattr_count = 1,
+};
+
DEFINE_LSM(evm) = {
.name = "evm",
.init = init_evm_lsm,
.order = LSM_ORDER_LAST,
+ .blobs = &evm_blob_sizes,
};
late_initcall(init_evm);
@@ -520,7 +520,7 @@ 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:
@@ -37,7 +37,6 @@
#define IMA_DIGSIG_REQUIRED 0x01000000
#define IMA_PERMIT_DIRECTIO 0x02000000
#define IMA_NEW_FILE 0x04000000
-#define EVM_IMMUTABLE_DIGSIG 0x08000000
#define IMA_FAIL_UNVERIFIABLE_SIGS 0x10000000
#define IMA_MODSIG_ALLOWED 0x20000000
#define IMA_CHECK_BLACKLIST 0x40000000
@@ -1716,8 +1716,8 @@ int security_inode_init_security(struct inode *inode, struct inode *dir,
return 0;
if (initxattrs) {
- /* Allocate +1 for EVM and +1 as terminator. */
- new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 2,
+ /* Allocate +1 as terminator. */
+ new_xattrs = kcalloc(blob_sizes.lbs_xattr_count + 1,
sizeof(*new_xattrs), GFP_NOFS);
if (!new_xattrs)
return -ENOMEM;