[PATCH 5.4 002/183] io_uring: drop any code related to SCM_RIGHTS

From: Sasha Levin
Date: Mon Mar 25 2024 - 07:52:05 EST


From: Jens Axboe <axboe@xxxxxxxxx>

Commit 6e5e6d274956305f1fc0340522b38f5f5be74bdb upstream.

This is dead code after we dropped support for passing io_uring fds
over SCM_RIGHTS, get rid of it.

Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/io_uring.c | 47 +++--------------------------------------------
1 file changed, 3 insertions(+), 44 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index cd1858cc63206..2c793e4ccf096 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -63,7 +63,6 @@
#include <linux/net.h>
#include <net/sock.h>
#include <net/af_unix.h>
-#include <net/scm.h>
#include <linux/anon_inodes.h>
#include <linux/sched/mm.h>
#include <linux/uaccess.h>
@@ -264,10 +263,6 @@ struct io_ring_ctx {

struct async_list pending_async[2];

-#if defined(CONFIG_UNIX)
- struct socket *ring_sock;
-#endif
-
struct list_head task_list;
spinlock_t task_lock;
};
@@ -3067,20 +3062,10 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,

static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
{
-#if defined(CONFIG_UNIX)
- if (ctx->ring_sock) {
- struct sock *sock = ctx->ring_sock->sk;
- struct sk_buff *skb;
-
- while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL)
- kfree_skb(skb);
- }
-#else
int i;

for (i = 0; i < ctx->nr_user_files; i++)
fput(ctx->user_files[i]);
-#endif
}

static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
@@ -3575,13 +3560,6 @@ static void io_ring_ctx_free(struct io_ring_ctx *ctx)
io_sqe_files_unregister(ctx);
io_eventfd_unregister(ctx);

-#if defined(CONFIG_UNIX)
- if (ctx->ring_sock) {
- ctx->ring_sock->file = NULL; /* so that iput() is called */
- sock_release(ctx->ring_sock);
- }
-#endif
-
io_mem_free(ctx->rings);
io_mem_free(ctx->sq_sqes);

@@ -3833,45 +3811,26 @@ static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
/*
* Allocate an anonymous fd, this is what constitutes the application
* visible backing of an io_uring instance. The application mmaps this
- * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
- * we have to tie this fd to a socket for file garbage collection purposes.
+ * fd to gain access to the SQ/CQ ring details.
*/
static int io_uring_get_fd(struct io_ring_ctx *ctx)
{
struct file *file;
int ret;

-#if defined(CONFIG_UNIX)
- ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
- &ctx->ring_sock);
- if (ret)
- return ret;
-#endif
-
ret = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
if (ret < 0)
- goto err;
+ return ret;

file = anon_inode_getfile("[io_uring]", &io_uring_fops, ctx,
O_RDWR | O_CLOEXEC);
if (IS_ERR(file)) {
put_unused_fd(ret);
- ret = PTR_ERR(file);
- goto err;
+ return PTR_ERR(file);
}

-#if defined(CONFIG_UNIX)
- ctx->ring_sock->file = file;
- ctx->ring_sock->sk->sk_user_data = ctx;
-#endif
fd_install(ret, file);
return ret;
-err:
-#if defined(CONFIG_UNIX)
- sock_release(ctx->ring_sock);
- ctx->ring_sock = NULL;
-#endif
- return ret;
}

static int io_uring_create(unsigned entries, struct io_uring_params *p)
--
2.43.0