From 53e9e0ced4e4146ff57635c8ee65a57f3ed33fe3 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@kernel.dk>
Date: Wed, 13 Mar 2024 18:33:48 -0600
Subject: [PATCH 1/2] io_uring/unix: drop usage of io_uring socket

Commit a4104821ad651d8a0b374f0b2474c345bbb42f82 upstream.

Since we no longer allow sending io_uring fds over SCM_RIGHTS, move to
using io_is_uring_fops() to detect whether this is a io_uring fd or not.
With that done, kill off io_uring_get_socket() as nobody calls it
anymore.

This is in preparation to yanking out the rest of the core related to
unix gc with io_uring.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 fs/io_uring.c      | 18 +++++-------------
 include/linux/fs.h |  6 +++---
 net/core/scm.c     |  2 +-
 net/unix/scm.c     |  4 +---
 4 files changed, 10 insertions(+), 20 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 9de8961763b0..cd1858cc6320 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -381,19 +381,6 @@ 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 void io_ring_ctx_ref_free(struct percpu_ref *ref)
 {
 	struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);
@@ -3794,6 +3781,11 @@ static const struct file_operations io_uring_fops = {
 	.fasync		= io_uring_fasync,
 };
 
+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/include/linux/fs.h b/include/linux/fs.h
index e009b52ab6b0..272f261894b1 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3614,11 +3614,11 @@ extern int generic_fadvise(struct file *file, loff_t offset, loff_t len,
 			   int advice);
 
 #if defined(CONFIG_IO_URING)
-extern struct sock *io_uring_get_socket(struct file *file);
+bool io_is_uring_fops(struct file *file);
 #else
-static inline struct sock *io_uring_get_socket(struct file *file)
+static inline bool io_is_uring_fops(struct file *file)
 {
-	return NULL;
+	return false;
 }
 #endif
 
diff --git a/net/core/scm.c b/net/core/scm.c
index 5525c14f33f1..a442bf63cd48 100644
--- 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_uring_get_socket(file)) {
+		if (io_is_uring_fops(file)) {
 			fput(file);
 			return -EINVAL;
 		}
diff --git a/net/unix/scm.c b/net/unix/scm.c
index e881a6e78af5..51b623de3be5 100644
--- a/net/unix/scm.c
+++ b/net/unix/scm.c
@@ -33,10 +33,8 @@ 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);
-- 
2.43.0