Newly created empty files do not get initial security.ima
value because iversion does not change. It can be checked from
the shell as:

  $ (exec >foo)
  $ getfattr -h -e hex -d -m security foo

This patch defines IMA_NEW_FILE flag which is set when IMA detects that new
file is created. It is checked upon ima_file_free hook to set initial
security.ima value.

Signed-off-by: Dmitry Kasatkin <[email protected]>
---
 security/integrity/ima/ima_appraise.c |  7 +++++--
 security/integrity/ima/ima_main.c     | 12 +++++++-----
 security/integrity/integrity.h        |  1 +
 3 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/security/integrity/ima/ima_appraise.c 
b/security/integrity/ima/ima_appraise.c
index 9dd18b5..3a4beb3 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -194,8 +194,11 @@ int ima_appraise_measurement(int func, struct 
integrity_iint_cache *iint,
                        goto out;
 
                cause = "missing-hash";
-               status =
-                   (inode->i_size == 0) ? INTEGRITY_PASS : INTEGRITY_NOLABEL;
+               status = INTEGRITY_NOLABEL;
+               if (inode->i_size == 0) {
+                       iint->flags |= IMA_NEW_FILE;
+                       status = INTEGRITY_PASS;
+               }
                goto out;
        }
 
diff --git a/security/integrity/ima/ima_main.c 
b/security/integrity/ima/ima_main.c
index e51e0d5..5a870e7 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -124,11 +124,13 @@ static void ima_check_last_writer(struct 
integrity_iint_cache *iint,
                return;
 
        mutex_lock(&iint->mutex);
-       if (atomic_read(&inode->i_writecount) == 1 &&
-           iint->version != inode->i_version) {
-               iint->flags &= ~IMA_DONE_MASK;
-               if (iint->flags & IMA_APPRAISE)
-                       ima_update_xattr(iint, file);
+       if (atomic_read(&inode->i_writecount) == 1) {
+               if ((iint->version != inode->i_version) ||
+                   (iint->flags & IMA_NEW_FILE)) {
+                       iint->flags &= ~(IMA_DONE_MASK | IMA_NEW_FILE);
+                       if (iint->flags & IMA_APPRAISE)
+                               ima_update_xattr(iint, file);
+               }
        }
        mutex_unlock(&iint->mutex);
 }
diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
index 92c1083..7656d47 100644
--- a/security/integrity/integrity.h
+++ b/security/integrity/integrity.h
@@ -30,6 +30,7 @@
 #define IMA_ACTION_FLAGS       0xff000000
 #define IMA_DIGSIG_REQUIRED    0x01000000
 #define IMA_PERMIT_DIRECTIO    0x02000000
+#define IMA_NEW_FILE           0x04000000
 
 #define IMA_DO_MASK            (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \
                                 IMA_APPRAISE_SUBMASK)
-- 
1.9.1

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