pidfs: switch to copy_struct_to_user()

We have a helper that deals with all the required logic.

Link: https://lore.kernel.org/r/20250305-work-pidfs-kill_on_last_close-v3-1-c8c3d8361705@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/pidfs.c b/fs/pidfs.c
index 049352f973de38967ad35c6440b9480e7e2e2775..aa8c8bda8c8f0a076e0464bf254d6f780272934e 100644 (file)
--- a/fs/pidfs.c
+++ b/fs/pidfs.c
@@ -276,10 +276,7 @@ static long pidfd_info(struct task_struct *task, unsigned int cmd, unsigned long
         * userspace knows about will be copied. If userspace provides a new
         * struct, only the bits that the kernel knows about will be copied.
         */
-       if (copy_to_user(uinfo, &kinfo, min(usize, sizeof(kinfo))))
-               return -EFAULT;
-
-       return 0;
+       return copy_struct_to_user(uinfo, usize, &kinfo, sizeof(kinfo), NULL);
 }
 
 static bool pidfs_ioctl_valid(unsigned int cmd)