[PATCH v6 01/10] file: Export receive_fd() to modules

[Xie Yongji <xieyongji@bytedance.com>]

Export receive_fd() so that some modules can use
it to pass file descriptor between processes without
missing any security stuffs.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
---
 fs/file.c            | 6 ++++++
 include/linux/file.h | 7 +++----
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/fs/file.c b/fs/file.c
index dab120b71e44..d7d957217576 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -1108,6 +1108,12 @@ int __receive_fd(int fd, struct file *file, int __user *ufd, unsigned int o_flag
 	return new_fd;
 }
 
+int receive_fd(struct file *file, unsigned int o_flags)
+{
+	return __receive_fd(-1, file, NULL, o_flags);
+}
+EXPORT_SYMBOL(receive_fd);
+
 static int ksys_dup3(unsigned int oldfd, unsigned int newfd, int flags)
 {
 	int err = -EBADF;
diff --git a/include/linux/file.h b/include/linux/file.h
index 225982792fa2..4667f9567d3e 100644
--- a/include/linux/file.h
+++ b/include/linux/file.h
@@ -94,6 +94,9 @@ extern void fd_install(unsigned int fd, struct file *file);
 
 extern int __receive_fd(int fd, struct file *file, int __user *ufd,
 			unsigned int o_flags);
+
+extern int receive_fd(struct file *file, unsigned int o_flags);
+
 static inline int receive_fd_user(struct file *file, int __user *ufd,
 				  unsigned int o_flags)
 {
@@ -101,10 +104,6 @@ static inline int receive_fd_user(struct file *file, int __user *ufd,
 		return -EFAULT;
 	return __receive_fd(-1, file, ufd, o_flags);
 }
-static inline int receive_fd(struct file *file, unsigned int o_flags)
-{
-	return __receive_fd(-1, file, NULL, o_flags);
-}
 static inline int receive_fd_replace(int fd, struct file *file, unsigned int o_flags)
 {
 	return __receive_fd(fd, file, NULL, o_flags);
-- 
2.11.0