* [PATCH 1/2] io_uring/unix: drop usage of io_uring socket
2023-12-19 19:42 [PATCHSET 0/2] Drop remnants of SCM_RIGHTS support Jens Axboe
@ 2023-12-19 19:42 ` Jens Axboe
2023-12-19 19:42 ` [PATCH 2/2] io_uring: drop any code related to SCM_RIGHTS Jens Axboe
1 sibling, 0 replies; 3+ messages in thread
From: Jens Axboe @ 2023-12-19 19:42 UTC (permalink / raw)
To: io-uring; +Cc: asml.silence, Jens Axboe
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 <[email protected]>
---
include/linux/io_uring.h | 10 +++++-----
io_uring/io_uring.c | 13 -------------
io_uring/io_uring.h | 1 -
net/core/scm.c | 2 +-
net/unix/scm.c | 4 +---
5 files changed, 7 insertions(+), 23 deletions(-)
diff --git a/include/linux/io_uring.h b/include/linux/io_uring.h
index d8fc93492dc5..68ed6697fece 100644
--- a/include/linux/io_uring.h
+++ b/include/linux/io_uring.h
@@ -7,12 +7,12 @@
#include <uapi/linux/io_uring.h>
#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);
void io_uring_unreg_ringfd(void);
const char *io_uring_get_opcode(u8 opcode);
int io_uring_cmd_sock(struct io_uring_cmd *cmd, unsigned int issue_flags);
+bool io_is_uring_fops(struct file *file);
static inline void io_uring_files_cancel(void)
{
@@ -32,10 +32,6 @@ 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)
{
}
@@ -54,6 +50,10 @@ static inline int io_uring_cmd_sock(struct io_uring_cmd *cmd,
{
return -EOPNOTSUPP;
}
+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 2b24ce692b0b..a9acccd45880 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -171,19 +171,6 @@ static struct ctl_table kernel_io_uring_disabled_table[] = {
};
#endif
-struct sock *io_uring_get_socket(struct file *file)
-{
-#if defined(CONFIG_UNIX)
- if (io_is_uring_fops(file)) {
- 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_submit_flush_completions(struct io_ring_ctx *ctx)
{
if (!wq_list_empty(&ctx->submit_state.compl_reqs) ||
diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h
index 1112c198e516..04e33f25919c 100644
--- a/io_uring/io_uring.h
+++ b/io_uring/io_uring.h
@@ -44,7 +44,6 @@ struct file *io_file_get_fixed(struct io_kiocb *req, int fd,
unsigned issue_flags);
void __io_req_task_work_add(struct io_kiocb *req, unsigned flags);
-bool io_is_uring_fops(struct file *file);
bool io_alloc_async_data(struct io_kiocb *req);
void io_req_task_queue(struct io_kiocb *req);
void io_queue_iowq(struct io_kiocb *req, struct io_tw_state *ts_dont_use);
diff --git a/net/core/scm.c b/net/core/scm.c
index db3f7cd519c2..d0e0852a24d5 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 6ff628f2349f..822ce0d0d791 100644
--- a/net/unix/scm.c
+++ b/net/unix/scm.c
@@ -35,10 +35,8 @@ struct sock *unix_get_socket(struct file *filp)
/* PF_UNIX ? */
if (s && ops && 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
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH 2/2] io_uring: drop any code related to SCM_RIGHTS
2023-12-19 19:42 [PATCHSET 0/2] Drop remnants of SCM_RIGHTS support Jens Axboe
2023-12-19 19:42 ` [PATCH 1/2] io_uring/unix: drop usage of io_uring socket Jens Axboe
@ 2023-12-19 19:42 ` Jens Axboe
1 sibling, 0 replies; 3+ messages in thread
From: Jens Axboe @ 2023-12-19 19:42 UTC (permalink / raw)
To: io-uring; +Cc: asml.silence, Jens Axboe
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 <[email protected]>
---
include/linux/io_uring_types.h | 3 -
io_uring/filetable.c | 11 +--
io_uring/io_uring.c | 32 +------
io_uring/rsrc.c | 169 +--------------------------------
io_uring/rsrc.h | 15 ---
5 files changed, 10 insertions(+), 220 deletions(-)
diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h
index bebab36abce8..fc8f2570b92b 100644
--- a/include/linux/io_uring_types.h
+++ b/include/linux/io_uring_types.h
@@ -389,9 +389,6 @@ struct io_ring_ctx {
struct wait_queue_head rsrc_quiesce_wq;
unsigned rsrc_quiesce;
- #if defined(CONFIG_UNIX)
- struct socket *ring_sock;
- #endif
/* hashed buffered write serialization */
struct io_wq_hash *hash_map;
diff --git a/io_uring/filetable.c b/io_uring/filetable.c
index e7d749991de4..6e86e6188dbe 100644
--- a/io_uring/filetable.c
+++ b/io_uring/filetable.c
@@ -87,13 +87,10 @@ static int io_install_fixed_file(struct io_ring_ctx *ctx, struct file *file,
io_file_bitmap_clear(&ctx->file_table, slot_index);
}
- ret = io_scm_file_account(ctx, file);
- if (!ret) {
- *io_get_tag_slot(ctx->file_data, slot_index) = 0;
- io_fixed_file_set(file_slot, file);
- io_file_bitmap_set(&ctx->file_table, slot_index);
- }
- return ret;
+ *io_get_tag_slot(ctx->file_data, slot_index) = 0;
+ io_fixed_file_set(file_slot, file);
+ io_file_bitmap_set(&ctx->file_table, slot_index);
+ return 0;
}
int __io_fixed_fd_install(struct io_ring_ctx *ctx, struct file *file,
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index a9acccd45880..a9a519fa9926 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -60,7 +60,6 @@
#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>
@@ -2866,13 +2865,6 @@ static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx)
io_rsrc_node_destroy(ctx, ctx->rsrc_node);
WARN_ON_ONCE(!list_empty(&ctx->rsrc_ref_list));
-
-#if defined(CONFIG_UNIX)
- if (ctx->ring_sock) {
- ctx->ring_sock->file = NULL; /* so that iput() is called */
- sock_release(ctx->ring_sock);
- }
-#endif
WARN_ON_ONCE(!list_empty(&ctx->ltimeout_list));
io_alloc_cache_free(&ctx->rsrc_node_cache, io_rsrc_node_cache_free);
@@ -3781,32 +3773,12 @@ static int io_uring_install_fd(struct file *file)
/*
* 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 struct file *io_uring_get_file(struct io_ring_ctx *ctx)
{
- struct file *file;
-#if defined(CONFIG_UNIX)
- int ret;
-
- ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
- &ctx->ring_sock);
- if (ret)
- return ERR_PTR(ret);
-#endif
-
- file = anon_inode_getfile_secure("[io_uring]", &io_uring_fops, ctx,
+ return anon_inode_getfile_secure("[io_uring]", &io_uring_fops, ctx,
O_RDWR | O_CLOEXEC, NULL);
-#if defined(CONFIG_UNIX)
- if (IS_ERR(file)) {
- sock_release(ctx->ring_sock);
- ctx->ring_sock = NULL;
- } else {
- ctx->ring_sock->file = file;
- }
-#endif
- return file;
}
static __cold int io_uring_create(unsigned entries, struct io_uring_params *p,
diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c
index f521c5965a93..4818b79231dd 100644
--- a/io_uring/rsrc.c
+++ b/io_uring/rsrc.c
@@ -24,7 +24,6 @@ struct io_rsrc_update {
};
static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);
-static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);
static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov,
struct io_mapped_ubuf **pimu,
struct page **last_hpage);
@@ -157,7 +156,7 @@ static void io_rsrc_put_work(struct io_rsrc_node *node)
switch (node->type) {
case IORING_RSRC_FILE:
- io_rsrc_file_put(node->ctx, prsrc);
+ fput(prsrc->file);
break;
case IORING_RSRC_BUFFER:
io_rsrc_buf_put(node->ctx, prsrc);
@@ -402,23 +401,13 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx,
break;
}
/*
- * Don't allow io_uring instances to be registered. If
- * UNIX isn't enabled, then this causes a reference
- * cycle and this instance can never get freed. If UNIX
- * is enabled we'll handle it just fine, but there's
- * still no point in allowing a ring fd as it doesn't
- * support regular read/write anyway.
+ * Don't allow io_uring instances to be registered.
*/
if (io_is_uring_fops(file)) {
fput(file);
err = -EBADF;
break;
}
- err = io_scm_file_account(ctx, file);
- if (err) {
- fput(file);
- break;
- }
*io_get_tag_slot(data, i) = tag;
io_fixed_file_set(file_slot, file);
io_file_bitmap_set(&ctx->file_table, i);
@@ -675,22 +664,12 @@ void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
for (i = 0; i < ctx->nr_user_files; i++) {
struct file *file = io_file_from_index(&ctx->file_table, i);
- /* skip scm accounted files, they'll be freed by ->ring_sock */
- if (!file || io_file_need_scm(file))
+ if (!file)
continue;
io_file_bitmap_clear(&ctx->file_table, i);
fput(file);
}
-#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);
- }
-#endif
io_free_file_tables(&ctx->file_table);
io_file_table_set_alloc_range(ctx, 0, 0);
io_rsrc_data_free(ctx->file_data);
@@ -718,137 +697,6 @@ int io_sqe_files_unregister(struct io_ring_ctx *ctx)
return ret;
}
-/*
- * Ensure the UNIX gc is aware of our file set, so we are certain that
- * the io_uring can be safely unregistered on process exit, even if we have
- * loops in the file referencing. We account only files that can hold other
- * files because otherwise they can't form a loop and so are not interesting
- * for GC.
- */
-int __io_scm_file_account(struct io_ring_ctx *ctx, struct file *file)
-{
-#if defined(CONFIG_UNIX)
- struct sock *sk = ctx->ring_sock->sk;
- struct sk_buff_head *head = &sk->sk_receive_queue;
- struct scm_fp_list *fpl;
- struct sk_buff *skb;
-
- if (likely(!io_file_need_scm(file)))
- return 0;
-
- /*
- * See if we can merge this file into an existing skb SCM_RIGHTS
- * file set. If there's no room, fall back to allocating a new skb
- * and filling it in.
- */
- spin_lock_irq(&head->lock);
- skb = skb_peek(head);
- if (skb && UNIXCB(skb).fp->count < SCM_MAX_FD)
- __skb_unlink(skb, head);
- else
- skb = NULL;
- spin_unlock_irq(&head->lock);
-
- if (!skb) {
- fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
- if (!fpl)
- return -ENOMEM;
-
- skb = alloc_skb(0, GFP_KERNEL);
- if (!skb) {
- kfree(fpl);
- return -ENOMEM;
- }
-
- fpl->user = get_uid(current_user());
- fpl->max = SCM_MAX_FD;
- fpl->count = 0;
-
- UNIXCB(skb).fp = fpl;
- skb->sk = sk;
- skb->destructor = io_uring_destruct_scm;
- refcount_add(skb->truesize, &sk->sk_wmem_alloc);
- }
-
- fpl = UNIXCB(skb).fp;
- fpl->fp[fpl->count++] = get_file(file);
- unix_inflight(fpl->user, file);
- skb_queue_head(head, skb);
- fput(file);
-#endif
- return 0;
-}
-
-static __cold void io_rsrc_file_scm_put(struct io_ring_ctx *ctx, struct file *file)
-{
-#if defined(CONFIG_UNIX)
- struct sock *sock = ctx->ring_sock->sk;
- struct sk_buff_head list, *head = &sock->sk_receive_queue;
- struct sk_buff *skb;
- int i;
-
- __skb_queue_head_init(&list);
-
- /*
- * Find the skb that holds this file in its SCM_RIGHTS. When found,
- * remove this entry and rearrange the file array.
- */
- skb = skb_dequeue(head);
- while (skb) {
- struct scm_fp_list *fp;
-
- fp = UNIXCB(skb).fp;
- for (i = 0; i < fp->count; i++) {
- int left;
-
- if (fp->fp[i] != file)
- continue;
-
- unix_notinflight(fp->user, fp->fp[i]);
- left = fp->count - 1 - i;
- if (left) {
- memmove(&fp->fp[i], &fp->fp[i + 1],
- left * sizeof(struct file *));
- }
- fp->count--;
- if (!fp->count) {
- kfree_skb(skb);
- skb = NULL;
- } else {
- __skb_queue_tail(&list, skb);
- }
- fput(file);
- file = NULL;
- break;
- }
-
- if (!file)
- break;
-
- __skb_queue_tail(&list, skb);
-
- skb = skb_dequeue(head);
- }
-
- if (skb_peek(&list)) {
- spin_lock_irq(&head->lock);
- while ((skb = __skb_dequeue(&list)) != NULL)
- __skb_queue_tail(head, skb);
- spin_unlock_irq(&head->lock);
- }
-#endif
-}
-
-static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
-{
- struct file *file = prsrc->file;
-
- if (likely(!io_file_need_scm(file)))
- fput(file);
- else
- io_rsrc_file_scm_put(ctx, file);
-}
-
int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
unsigned nr_args, u64 __user *tags)
{
@@ -897,21 +745,12 @@ int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
goto fail;
/*
- * Don't allow io_uring instances to be registered. If UNIX
- * isn't enabled, then this causes a reference cycle and this
- * instance can never get freed. If UNIX is enabled we'll
- * handle it just fine, but there's still no point in allowing
- * a ring fd as it doesn't support regular read/write anyway.
+ * Don't allow io_uring instances to be registered.
*/
if (io_is_uring_fops(file)) {
fput(file);
goto fail;
}
- ret = io_scm_file_account(ctx, file);
- if (ret) {
- fput(file);
- goto fail;
- }
file_slot = io_fixed_file_slot(&ctx->file_table, i);
io_fixed_file_set(file_slot, file);
io_file_bitmap_set(&ctx->file_table, i);
diff --git a/io_uring/rsrc.h b/io_uring/rsrc.h
index 08ac0d8e07ef..7238b9cfe33b 100644
--- a/io_uring/rsrc.h
+++ b/io_uring/rsrc.h
@@ -75,21 +75,6 @@ int io_sqe_files_unregister(struct io_ring_ctx *ctx);
int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
unsigned nr_args, u64 __user *tags);
-int __io_scm_file_account(struct io_ring_ctx *ctx, struct file *file);
-
-static inline bool io_file_need_scm(struct file *filp)
-{
- return false;
-}
-
-static inline int io_scm_file_account(struct io_ring_ctx *ctx,
- struct file *file)
-{
- if (likely(!io_file_need_scm(file)))
- return 0;
- return __io_scm_file_account(ctx, file);
-}
-
int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
unsigned nr_args);
int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
--
2.43.0
^ permalink raw reply related [flat|nested] 3+ messages in thread