Update Linux to v5.4.148
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz
Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c
index d485f6f..25dac69 100644
--- a/security/integrity/evm/evm_crypto.c
+++ b/security/integrity/evm/evm_crypto.c
@@ -75,7 +75,7 @@
{
long rc;
const char *algo;
- struct crypto_shash **tfm;
+ struct crypto_shash **tfm, *tmp_tfm = NULL;
struct shash_desc *desc;
if (type == EVM_XATTR_HMAC) {
@@ -93,40 +93,43 @@
algo = hash_algo_name[hash_algo];
}
- if (*tfm == NULL) {
- mutex_lock(&mutex);
- if (*tfm)
- goto out;
- *tfm = crypto_alloc_shash(algo, 0, CRYPTO_NOLOAD);
- if (IS_ERR(*tfm)) {
- rc = PTR_ERR(*tfm);
- pr_err("Can not allocate %s (reason: %ld)\n", algo, rc);
- *tfm = NULL;
+ if (*tfm)
+ goto alloc;
+ mutex_lock(&mutex);
+ if (*tfm)
+ goto unlock;
+
+ tmp_tfm = crypto_alloc_shash(algo, 0, CRYPTO_NOLOAD);
+ if (IS_ERR(tmp_tfm)) {
+ pr_err("Can not allocate %s (reason: %ld)\n", algo,
+ PTR_ERR(tmp_tfm));
+ mutex_unlock(&mutex);
+ return ERR_CAST(tmp_tfm);
+ }
+ if (type == EVM_XATTR_HMAC) {
+ rc = crypto_shash_setkey(tmp_tfm, evmkey, evmkey_len);
+ if (rc) {
+ crypto_free_shash(tmp_tfm);
mutex_unlock(&mutex);
return ERR_PTR(rc);
}
- if (type == EVM_XATTR_HMAC) {
- rc = crypto_shash_setkey(*tfm, evmkey, evmkey_len);
- if (rc) {
- crypto_free_shash(*tfm);
- *tfm = NULL;
- mutex_unlock(&mutex);
- return ERR_PTR(rc);
- }
- }
-out:
- mutex_unlock(&mutex);
}
-
+ *tfm = tmp_tfm;
+unlock:
+ mutex_unlock(&mutex);
+alloc:
desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(*tfm),
GFP_KERNEL);
- if (!desc)
+ if (!desc) {
+ crypto_free_shash(tmp_tfm);
return ERR_PTR(-ENOMEM);
+ }
desc->tfm = *tfm;
rc = crypto_shash_init(desc);
if (rc) {
+ crypto_free_shash(tmp_tfm);
kfree(desc);
return ERR_PTR(rc);
}
@@ -209,7 +212,7 @@
data->hdr.length = crypto_shash_digestsize(desc->tfm);
error = -ENODATA;
- list_for_each_entry_rcu(xattr, &evm_config_xattrnames, list) {
+ list_for_each_entry_lockless(xattr, &evm_config_xattrnames, list) {
bool is_ima = false;
if (strcmp(xattr->name, XATTR_NAME_IMA) == 0)
@@ -243,7 +246,7 @@
/* Portable EVM signatures must include an IMA hash */
if (type == EVM_XATTR_PORTABLE_DIGSIG && !ima_present)
- return -EPERM;
+ error = -EPERM;
out:
kfree(xattr_value);
kfree(desc);
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index f9a81b1..81e3245 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -99,7 +99,7 @@
if (!(inode->i_opflags & IOP_XATTR))
return -EOPNOTSUPP;
- list_for_each_entry_rcu(xattr, &evm_config_xattrnames, list) {
+ list_for_each_entry_lockless(xattr, &evm_config_xattrnames, list) {
error = __vfs_getxattr(dentry, inode, xattr->name, NULL, 0);
if (error < 0) {
if (error == -ENODATA)
@@ -183,6 +183,12 @@
break;
case EVM_IMA_XATTR_DIGSIG:
case EVM_XATTR_PORTABLE_DIGSIG:
+ /* accept xattr with non-empty signature field */
+ if (xattr_len <= sizeof(struct signature_v2_hdr)) {
+ evm_status = INTEGRITY_FAIL;
+ goto out;
+ }
+
hdr = (struct signature_v2_hdr *)xattr_data;
digest.hdr.algo = hdr->hash_algo;
rc = evm_calc_hash(dentry, xattr_name, xattr_value,
@@ -230,7 +236,7 @@
struct xattr_list *xattr;
namelen = strlen(req_xattr_name);
- list_for_each_entry_rcu(xattr, &evm_config_xattrnames, list) {
+ list_for_each_entry_lockless(xattr, &evm_config_xattrnames, list) {
if ((strlen(xattr->name) == namelen)
&& (strncmp(req_xattr_name, xattr->name, namelen) == 0)) {
found = 1;
@@ -514,7 +520,7 @@
}
/*
- * evm_inode_init_security - initializes security.evm
+ * evm_inode_init_security - initializes security.evm HMAC value
*/
int evm_inode_init_security(struct inode *inode,
const struct xattr *lsm_xattr,
@@ -523,7 +529,8 @@
struct evm_xattr *xattr_data;
int rc;
- if (!evm_key_loaded() || !evm_protected_xattr(lsm_xattr->name))
+ if (!(evm_initialized & EVM_INIT_HMAC) ||
+ !evm_protected_xattr(lsm_xattr->name))
return 0;
xattr_data = kzalloc(sizeof(*xattr_data), GFP_NOFS);
diff --git a/security/integrity/evm/evm_secfs.c b/security/integrity/evm/evm_secfs.c
index c11c1f7..d7f12ed 100644
--- a/security/integrity/evm/evm_secfs.c
+++ b/security/integrity/evm/evm_secfs.c
@@ -68,12 +68,13 @@
static ssize_t evm_write_key(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
- int i, ret;
+ unsigned int i;
+ int ret;
if (!capable(CAP_SYS_ADMIN) || (evm_initialized & EVM_SETUP_COMPLETE))
return -EPERM;
- ret = kstrtoint_from_user(buf, count, 0, &i);
+ ret = kstrtouint_from_user(buf, count, 0, &i);
if (ret)
return ret;
@@ -82,12 +83,12 @@
if (!i || (i & ~EVM_INIT_MASK) != 0)
return -EINVAL;
- /* Don't allow a request to freshly enable metadata writes if
- * keys are loaded.
+ /*
+ * Don't allow a request to enable metadata writes if
+ * an HMAC key is loaded.
*/
if ((i & EVM_ALLOW_METADATA_WRITES) &&
- ((evm_initialized & EVM_KEY_MASK) != 0) &&
- !(evm_initialized & EVM_ALLOW_METADATA_WRITES))
+ (evm_initialized & EVM_INIT_HMAC) != 0)
return -EPERM;
if (i & EVM_INIT_HMAC) {
@@ -234,7 +235,14 @@
goto out;
}
- /* Guard against races in evm_read_xattrs */
+ /*
+ * xattr_list_mutex guards against races in evm_read_xattrs().
+ * Entries are only added to the evm_config_xattrnames list
+ * and never deleted. Therefore, the list is traversed
+ * using list_for_each_entry_lockless() without holding
+ * the mutex in evm_calc_hmac_or_hash(), evm_find_protected_xattrs()
+ * and evm_protected_xattr().
+ */
mutex_lock(&xattr_list_mutex);
list_for_each_entry(tmp, &evm_config_xattrnames, list) {
if (strcmp(xattr->name, tmp->name) == 0) {