[PATCH] remove LSM file_llseek hook

In the initial discussion LSM folks agreed on this, the
rationale is that lsseek itself makes no sense to
project as mmap() and pread/pwrite() allow access to any
area of the file anyway.

fs/read_write.c

@@ -121,12 +121,6 @@ asmlinkage off_t sys_lseek(unsigned int fd, off_t offset, unsigned int origin)
 	if (!file)
 		goto bad;
 
-	retval = security_ops->file_llseek(file);
-	if (retval) {
-		fput(file);
-		goto bad;
-	}
-
 	retval = -EINVAL;
 	if (origin <= 2) {
 		loff_t res = llseek(file, offset, origin);
@@ -153,10 +147,6 @@ asmlinkage long sys_llseek(unsigned int fd, unsigned long offset_high,
 	if (!file)
 		goto bad;
 
-	retval = security_ops->file_llseek(file);
-	if (retval)
-		goto out_putf;
-
 	retval = -EINVAL;
 	if (origin > 2)
 		goto out_putf;

include/linux/security.h

@@ -376,10 +376,6 @@ struct swap_info_struct;
  * @file_free_security:
  *	Deallocate and free any security structures stored in file->f_security.
  *	@file contains the file structure being modified.
- * @file_llseek:
- *	Check permission before re-positioning the file offset in @file.
- *	@file contains the file structure being modified.
- *	Return 0 if permission is granted.
  * @file_ioctl:
  *	@file contains the file structure.
  *	@cmd contains the operation to perform.
@@ -790,7 +786,6 @@ struct security_operations {
 	int (*file_permission) (struct file * file, int mask);
 	int (*file_alloc_security) (struct file * file);
 	void (*file_free_security) (struct file * file);
-	int (*file_llseek) (struct file * file);
 	int (*file_ioctl) (struct file * file, unsigned int cmd,
 			   unsigned long arg);
 	int (*file_mmap) (struct file * file,

security/capability.c

@@ -442,11 +442,6 @@ static void cap_file_free_security (struct file *file)
 	return;
 }
 
-static int cap_file_llseek (struct file *file)
-{
-	return 0;
-}
-
 static int cap_file_ioctl (struct file *file, unsigned int command,
 			   unsigned long arg)
 {
@@ -787,7 +782,6 @@ static struct security_operations capability_ops = {
 	.file_permission =		cap_file_permission,
 	.file_alloc_security =		cap_file_alloc_security,
 	.file_free_security =		cap_file_free_security,
-	.file_llseek =			cap_file_llseek,
 	.file_ioctl =			cap_file_ioctl,
 	.file_mmap =			cap_file_mmap,
 	.file_mprotect =		cap_file_mprotect,

security/dummy.c

@@ -344,11 +344,6 @@ static void dummy_file_free_security (struct file *file)
 	return;
 }
 
-static int dummy_file_llseek (struct file *file)
-{
-	return 0;
-}
-
 static int dummy_file_ioctl (struct file *file, unsigned int command,
 			     unsigned long arg)
 {
@@ -602,7 +597,6 @@ struct security_operations dummy_security_ops = {
 	.file_permission =		dummy_file_permission,
 	.file_alloc_security =		dummy_file_alloc_security,
 	.file_free_security =		dummy_file_free_security,
-	.file_llseek =			dummy_file_llseek,
 	.file_ioctl =			dummy_file_ioctl,
 	.file_mmap =			dummy_file_mmap,
 	.file_mprotect =		dummy_file_mprotect,