Commit 642b151f authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity 

Pull integrity fixes from Mimi Zohar:
 "A couple of miscellaneous bug fixes for the integrity subsystem:

  IMA:

   - Properly modify the open flags in order to calculate the file hash.

   - On systems requiring the IMA policy to be signed, the policy is
     loaded differently. Don't differentiate between "enforce" and
     either "log" or "fix" modes how the policy is loaded.

  EVM:

   - Two patches to fix an EVM race condition, normally the result of
     attempting to load an unsupported hash algorithm.

   - Use the lockless RCU version for walking an append only list"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  evm: Fix a small race in init_desc()
  evm: Fix RCU list related warnings
  ima: Fix return value of ima_write_policy()
  evm: Check also if *tfm is an error pointer in init_desc()
  ima: Set file->f_mode instead of file->f_flags in ima_calc_file_hash()
parents 45088963 84338569

security/integrity/evm/evm_crypto.c

+23 −23
Original line number Diff line number Diff line
@@ -73,7 +73,7 @@ static struct shash_desc *init_desc(char type, uint8_t hash_algo) 
{

	long rc;

	const char *algo;

	struct crypto_shash **tfm;

	struct crypto_shash **tfm, *tmp_tfm;

	struct shash_desc *desc;



	if (type == EVM_XATTR_HMAC) {
@@ -91,31 +91,31 @@ static struct shash_desc *init_desc(char type, uint8_t hash_algo) 
		algo = hash_algo_name[hash_algo];

	}



	if (*tfm == NULL) {

	if (*tfm)

		goto alloc;

	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;

		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_PTR(rc);

		return ERR_CAST(tmp_tfm);

	}

	if (type == EVM_XATTR_HMAC) {

			rc = crypto_shash_setkey(*tfm, evmkey, evmkey_len);

		rc = crypto_shash_setkey(tmp_tfm, evmkey, evmkey_len);

		if (rc) {

				crypto_free_shash(*tfm);

				*tfm = NULL;

			crypto_free_shash(tmp_tfm);

			mutex_unlock(&mutex);

			return ERR_PTR(rc);

		}

	}

out:

	*tfm = tmp_tfm;

unlock:

	mutex_unlock(&mutex);

	}



alloc:

	desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(*tfm),

			GFP_KERNEL);

	if (!desc)
@@ -207,7 +207,7 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry, 
	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)

security/integrity/evm/evm_main.c

+2 −2
Original line number Diff line number Diff line
@@ -97,7 +97,7 @@ static int evm_find_protected_xattrs(struct dentry *dentry) 
	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)
@@ -228,7 +228,7 @@ static int evm_protected_xattr(const char *req_xattr_name) 
	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;

security/integrity/evm/evm_secfs.c

+8 −1
Original line number Diff line number Diff line
@@ -232,7 +232,14 @@ static ssize_t evm_write_xattrs(struct file *file, const char __user *buf, 
		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) {

security/integrity/ima/ima_crypto.c

+6 −6
Original line number Diff line number Diff line
@@ -411,7 +411,7 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash) 
	loff_t i_size;

	int rc;

	struct file *f = file;

	bool new_file_instance = false, modified_flags = false;

	bool new_file_instance = false, modified_mode = false;



	/*

	 * For consistency, fail file's opened with the O_DIRECT flag on
@@ -431,13 +431,13 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash) 
		f = dentry_open(&file->f_path, flags, file->f_cred);

		if (IS_ERR(f)) {

			/*

			 * Cannot open the file again, lets modify f_flags

			 * Cannot open the file again, lets modify f_mode

			 * of original and continue

			 */

			pr_info_ratelimited("Unable to reopen file for reading.\n");

			f = file;

			f->f_flags |= FMODE_READ;

			modified_flags = true;

			f->f_mode |= FMODE_READ;

			modified_mode = true;

		} else {

			new_file_instance = true;

		}
@@ -455,8 +455,8 @@ int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash) 
out:

	if (new_file_instance)

		fput(f);

	else if (modified_flags)

		f->f_flags &= ~FMODE_READ;

	else if (modified_mode)

		f->f_mode &= ~FMODE_READ;

	return rc;

}

security/integrity/ima/ima_fs.c

+1 −2
Original line number Diff line number Diff line
@@ -338,7 +338,6 @@ static ssize_t ima_write_policy(struct file *file, const char __user *buf, 
		integrity_audit_msg(AUDIT_INTEGRITY_STATUS, NULL, NULL,

				    "policy_update", "signed policy required",

				    1, 0);

		if (ima_appraise & IMA_APPRAISE_ENFORCE)

		result = -EACCES;

	} else {

		result = ima_parse_add_rule(data);

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