Untangling ima mess, part 3: kill dead code in ima

Kill the 'update' argument of ima_path_check(), kill
dead code in ima.

Current rules: ima counters are bumped at the same time
when the file switches from put_filp() fodder to fput()
one.  Which happens exactly in two places - alloc_file()
and __dentry_open().  Nothing else needs to do that at
all.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

4 files changed, 9 insertions, 62 deletions

diff --git a/fs/namei.c b/fs/namei.c
index c530e5d32f12..a765e7a741f4 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1686,7 +1686,7 @@ do_last:
                         path_put(&nd.root);
                 if (!IS_ERR(filp)) {
                         error = ima_path_check(&filp->f_path, filp->f_mode &
-                                       (MAY_READ | MAY_WRITE | MAY_EXEC), 0);
+                                       (MAY_READ | MAY_WRITE | MAY_EXEC));
                         if (error) {
                                 fput(filp);
                                 filp = ERR_PTR(error);
@@ -1747,7 +1747,7 @@ ok:
         filp = nameidata_to_filp(&nd, open_flag);
         if (!IS_ERR(filp)) {
                 error = ima_path_check(&filp->f_path, filp->f_mode &
-                               (MAY_READ | MAY_WRITE | MAY_EXEC), 0);
+                               (MAY_READ | MAY_WRITE | MAY_EXEC));
                 if (error) {
                         fput(filp);
                         filp = ERR_PTR(error);
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index c9942b39654e..936f08400db6 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -2122,8 +2122,7 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
          */
         path.mnt = exp->ex_path.mnt;
         path.dentry = dentry;
-        err = ima_path_check(&path, acc & (MAY_READ | MAY_WRITE | MAY_EXEC),
-                             IMA_COUNT_LEAVE);
+        err = ima_path_check(&path, acc & (MAY_READ | MAY_WRITE | MAY_EXEC));
 nfsd_out:
         return err? nfserrno(err) : 0;
 }
diff --git a/include/linux/ima.h b/include/linux/ima.h
index 0e3f2a4c25f6..99dc6d5cf7e5 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h
@@ -13,18 +13,14 @@
 #include <linux/fs.h>
 struct linux_binprm;
 
-#define IMA_COUNT_UPDATE 1
-#define IMA_COUNT_LEAVE 0
-
 #ifdef CONFIG_IMA
 extern int ima_bprm_check(struct linux_binprm *bprm);
 extern int ima_inode_alloc(struct inode *inode);
 extern void ima_inode_free(struct inode *inode);
-extern int ima_path_check(struct path *path, int mask, int update_counts);
+extern int ima_path_check(struct path *path, int mask);
 extern void ima_file_free(struct file *file);
 extern int ima_file_mmap(struct file *file, unsigned long prot);
 extern void ima_counts_get(struct file *file);
-extern void ima_counts_put(struct path *path, int mask);
 
 #else
 static inline int ima_bprm_check(struct linux_binprm *bprm)
@@ -42,7 +38,7 @@ static inline void ima_inode_free(struct inode *inode)
         return;
 }
 
-static inline int ima_path_check(struct path *path, int mask, int update_counts)
+static inline int ima_path_check(struct path *path, int mask)
 {
         return 0;
 }
@@ -62,9 +58,5 @@ static inline void ima_counts_get(struct file *file)
         return;
 }
 
-static inline void ima_counts_put(struct path *path, int mask)
-{
-        return;
-}
 #endif /* CONFIG_IMA_H */
 #endif /* _LINUX_IMA_H */
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index e041233b4d2a..16dc57d247d0 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -50,19 +50,12 @@ static void ima_inc_counts(struct ima_iint_cache *iint, fmode_t mode)
 }
 
 /*
- * Update the counts given open flags instead of fmode
- */
-static void ima_inc_counts_flags(struct ima_iint_cache *iint, int flags)
-{
-        ima_inc_counts(iint, (__force fmode_t)((flags+1) & O_ACCMODE));
-}
-
-/*
  * Decrement ima counts
  */
 static void ima_dec_counts(struct ima_iint_cache *iint, struct inode *inode,
-                           fmode_t mode)
+                           struct file *file)
 {
+        mode_t mode = file->f_mode;
         BUG_ON(!mutex_is_locked(&iint->mutex));
 
         iint->opencount--;
@@ -92,12 +85,6 @@ static void ima_dec_counts(struct ima_iint_cache *iint, struct inode *inode,
         }
 }
 
-static void ima_dec_counts_flags(struct ima_iint_cache *iint,
-                                 struct inode *inode, int flags)
-{
-        ima_dec_counts(iint, inode, (__force fmode_t)((flags+1) & O_ACCMODE));
-}
-
 /**
  * ima_file_free - called on __fput()
  * @file: pointer to file structure being freed
@@ -117,7 +104,7 @@ void ima_file_free(struct file *file)
                 return;
 
         mutex_lock(&iint->mutex);
-        ima_dec_counts(iint, inode, file->f_mode);
+        ima_dec_counts(iint, inode, file);
         mutex_unlock(&iint->mutex);
         kref_put(&iint->refcount, iint_free);
 }
@@ -183,7 +170,7 @@ static int get_path_measurement(struct ima_iint_cache *iint, struct file *file,
  * Always return 0 and audit dentry_open failures.
  * (Return code will be based upon measurement appraisal.)
  */
-int ima_path_check(struct path *path, int mask, int update_counts)
+int ima_path_check(struct path *path, int mask)
 {
         struct inode *inode = path->dentry->d_inode;
         struct ima_iint_cache *iint;
@@ -197,8 +184,6 @@ int ima_path_check(struct path *path, int mask, int update_counts)
                 return 0;
 
         mutex_lock(&iint->mutex);
-        if (update_counts)
-                ima_inc_counts_flags(iint, mask);
 
         rc = ima_must_measure(iint, inode, MAY_READ, PATH_CHECK);
         if (rc < 0)
@@ -269,35 +254,6 @@ out:
 }
 
 /*
- * ima_counts_put - decrement file counts
- *
- * File counts are incremented in ima_path_check. On file open
- * error, such as ETXTBSY, decrement the counts to prevent
- * unnecessary imbalance messages.
- */
-void ima_counts_put(struct path *path, int mask)
-{
-        struct inode *inode = path->dentry->d_inode;
-        struct ima_iint_cache *iint;
-
-        /* The inode may already have been freed, freeing the iint
-         * with it. Verify the inode is not NULL before dereferencing
-         * it.
-         */
-        if (!ima_initialized || !inode || !S_ISREG(inode->i_mode))
-                return;
-        iint = ima_iint_find_get(inode);
-        if (!iint)
-                return;
-
-        mutex_lock(&iint->mutex);
-        ima_dec_counts_flags(iint, inode, mask);
-        mutex_unlock(&iint->mutex);
-
-        kref_put(&iint->refcount, iint_free);
-}
-
-/*
  * ima_counts_get - increment file counts
  *
  * - for IPC shm and shmat file.