vfs: define kernel_read_file_id enumeration

To differentiate between the kernel_read_file() callers, this patch
defines a new enumeration named kernel_read_file_id and includes the
caller identifier as an argument.

Subsequent patches define READING_KEXEC_IMAGE, READING_KEXEC_INITRAMFS,
READING_FIRMWARE, READING_MODULE, and READING_POLICY.

Changelog v3:
- Replace the IMA specific enumeration with a generic one.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 6 insertions, 1 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 9a83d82..aa84bcb 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2576,8 +2576,13 @@ static inline void i_readcount_inc(struct inode *inode)
 #endif
 extern int do_pipe_flags(int *, int);
 
+enum kernel_read_file_id {
+	READING_MAX_ID
+};
+
 extern int kernel_read(struct file *, loff_t, char *, unsigned long);
-extern int kernel_read_file(struct file *, void **, loff_t *, loff_t);
+extern int kernel_read_file(struct file *, void **, loff_t *, loff_t,
+			    enum kernel_read_file_id);
 extern ssize_t kernel_write(struct file *, const char *, size_t, loff_t);
 extern ssize_t __kernel_write(struct file *, const char *, size_t, loff_t *);
 extern struct file * open_exec(const char *);