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()

1 files changed, 8 insertions, 1 deletions

diff --git a/security/integrity/evm/evm_secfs.c b/security/integrity/evm/evm_secfs.c
index 39ad1038d45d..cfc3075769bb 100644
--- a/security/integrity/evm/evm_secfs.c
+++ b/security/integrity/evm/evm_secfs.c
@@ -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) {