Integrity: IMA file free imbalance
The number of calls to ima_path_check()/ima_file_free()
should be balanced. An extra call to fput(), indicates
the file could have been accessed without first being
measured.
Although f_count is incremented/decremented in places other
than fget/fput, like fget_light/fput_light and get_file, the
current task must already hold a file refcnt. The call to
__fput() is delayed until the refcnt becomes 0, resulting
in ima_file_free() flagging any changes.
- add hook to increment opencount for IPC shared memory(SYSV),
shmat files, and /dev/zero
- moved NULL iint test in opencount_get()
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/mm/shmem.c b/mm/shmem.c
index f1b0d48..dd5588f 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -51,6 +51,7 @@
#include <linux/highmem.h>
#include <linux/seq_file.h>
#include <linux/magic.h>
+#include <linux/ima.h>
#include <asm/uaccess.h>
#include <asm/div64.h>
@@ -2600,6 +2601,7 @@
if (IS_ERR(file))
return PTR_ERR(file);
+ ima_shm_check(file);
if (vma->vm_file)
fput(vma->vm_file);
vma->vm_file = file;