| Message ID | 20210517095513.850-3-xieyongji@bytedance.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Introduce VDUSE - vDPA Device in Userspace | expand |
On Mon, May 17, 2021 at 05:55:03PM +0800, Xie Yongji wrote: > Export receive_fd() so that some modules can use > it to pass file descriptor between processes without > missing any security stuffs. Which tree is that against? Because in mainline this won't even build, let alone work. > --- a/fs/file.c > +++ b/fs/file.c > @@ -1135,6 +1135,12 @@ 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_GPL(receive_fd); fs/file.c:1097:int __receive_fd(struct file *file, int __user *ufd, unsigned int o_flags)
On Thu, May 20, 2021 at 2:18 PM Al Viro <viro@zeniv.linux.org.uk> wrote: > > On Mon, May 17, 2021 at 05:55:03PM +0800, Xie Yongji wrote: > > Export receive_fd() so that some modules can use > > it to pass file descriptor between processes without > > missing any security stuffs. > > Which tree is that against? Because in mainline this won't even build, let > alone work. > Oh, sorry for that. Now I'm based on vhost.git tree. But looks like I miss Christoph's commit 42eb0d54c08 ("fs: split receive_fd_replace from __receive_fd"). Will rebase on it in v8. Thanks, Yongji
diff --git a/fs/file.c b/fs/file.c index f633348029a5..ef4da2eaf25b 100644 --- a/fs/file.c +++ b/fs/file.c @@ -1135,6 +1135,12 @@ 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_GPL(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);
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(-)