From 809ca90c02649cd2e566f2a926147e3e63b91d2f Mon Sep 17 00:00:00 2001
From: Ksawlii <ksawlii.do.plikow@gmail.com>
Date: Tue, 19 Nov 2024 09:11:51 +0100
Subject: [PATCH] Revert "io_uring/unix: drop usage of io_uring socket"

This reverts commit 6cf9b744bfd4459be3b8520923a48dbec277e460.
---
 include/linux/io_uring.h | 10 +++++-----
 io_uring/io_uring.c      | 18 +++++++++++++-----
 net/core/scm.c           |  2 +-
 net/unix/scm.c           |  4 +++-
 4 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/include/linux/io_uring.h b/include/linux/io_uring.h
index d02731868..5ae871af4 100755
--- a/include/linux/io_uring.h
+++ b/include/linux/io_uring.h
@@ -68,9 +68,9 @@ struct io_uring_task {
 
 
 #if defined(CONFIG_IO_URING)
+struct sock *io_uring_get_socket(struct file *file);
 void __io_uring_cancel(bool cancel_all);
 void __io_uring_free(struct task_struct *tsk);
-bool io_is_uring_fops(struct file *file);
 
 static inline void io_uring_files_cancel(void)
 {
@@ -88,6 +88,10 @@ static inline void io_uring_free(struct task_struct *tsk)
 		__io_uring_free(tsk);
 }
 #else
+static inline struct sock *io_uring_get_socket(struct file *file)
+{
+	return NULL;
+}
 static inline void io_uring_task_cancel(void)
 {
 }
@@ -97,10 +101,6 @@ static inline void io_uring_files_cancel(void)
 static inline void io_uring_free(struct task_struct *tsk)
 {
 }
-static inline bool io_is_uring_fops(struct file *file)
-{
-	return false;
-}
 #endif
 
 #endif
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 6d0828bcb..41f1124d9 100755
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -1119,6 +1119,19 @@ static struct kmem_cache *req_cachep;
 
 static const struct file_operations io_uring_fops;
 
+struct sock *io_uring_get_socket(struct file *file)
+{
+#if defined(CONFIG_UNIX)
+	if (file->f_op == &io_uring_fops) {
+		struct io_ring_ctx *ctx = file->private_data;
+
+		return ctx->ring_sock->sk;
+	}
+#endif
+	return NULL;
+}
+EXPORT_SYMBOL(io_uring_get_socket);
+
 static inline void io_tw_lock(struct io_ring_ctx *ctx, bool *locked)
 {
 	if (!*locked) {
@@ -10086,11 +10099,6 @@ static const struct file_operations io_uring_fops = {
 #endif
 };
 
-bool io_is_uring_fops(struct file *file)
-{
-	return file->f_op == &io_uring_fops;
-}
-
 static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
 				  struct io_uring_params *p)
 {
diff --git a/net/core/scm.c b/net/core/scm.c
index d09849cb6..3c7f16072 100755
--- a/net/core/scm.c
+++ b/net/core/scm.c
@@ -105,7 +105,7 @@ static int scm_fp_copy(struct cmsghdr *cmsg, struct scm_fp_list **fplp)
 		if (fd < 0 || !(file = fget_raw(fd)))
 			return -EBADF;
 		/* don't allow io_uring files */
-		if (io_is_uring_fops(file)) {
+		if (io_uring_get_socket(file)) {
 			fput(file);
 			return -EINVAL;
 		}
diff --git a/net/unix/scm.c b/net/unix/scm.c
index d1048b4c2..e8e2a00bb 100755
--- a/net/unix/scm.c
+++ b/net/unix/scm.c
@@ -34,8 +34,10 @@ struct sock *unix_get_socket(struct file *filp)
 		/* PF_UNIX ? */
 		if (s && sock->ops && sock->ops->family == PF_UNIX)
 			u_sock = s;
+	} else {
+		/* Could be an io_uring instance */
+		u_sock = io_uring_get_socket(filp);
 	}
-
 	return u_sock;
 }
 EXPORT_SYMBOL(unix_get_socket);