Merge tag 'io_uring-6.1-2022-10-20' of git://git.kernel.dk/linux

Pull io_uring fixes from Jens Axboe:

 - Fix a potential memory leak in the error handling path of io-wq setup
   (Rafael)

 - Kill an errant debug statement that got added in this release (me)

 - Fix an oops with an invalid direct descriptor with IORING_OP_MSG_RING
   (Harshit)

 - Remove unneeded FFS_SCM flagging (Pavel)

 - Remove polling off the exit path (Pavel)

 - Move out direct descriptor debug check to the cleanup path (Pavel)

 - Use the proper helper rather than open-coding cached request get
   (Pavel)

* tag 'io_uring-6.1-2022-10-20' of git://git.kernel.dk/linux:
  io-wq: Fix memory leak in worker creation
  io_uring/msg_ring: Fix NULL pointer dereference in io_msg_send_fd()
  io_uring/rw: remove leftover debug statement
  io_uring: don't iopoll from io_ring_ctx_wait_and_kill()
  io_uring: reuse io_alloc_req()
  io_uring: kill hot path fixed file bitmap debug checks
  io_uring: remove FFS_SCM

Author: torvalds

io_uring/filetable.h

@@ -5,22 +5,9 @@
 #include <linux/file.h>
 #include <linux/io_uring_types.h>
 
-/*
- * FFS_SCM is only available on 64-bit archs, for 32-bit we just define it as 0
- * and define IO_URING_SCM_ALL. For this case, we use SCM for all files as we
- * can't safely always dereference the file when the task has exited and ring
- * cleanup is done. If a file is tracked and part of SCM, then unix gc on
- * process exit may reap it before __io_sqe_files_unregister() is run.
- */
 #define FFS_NOWAIT		0x1UL
 #define FFS_ISREG		0x2UL
-#if defined(CONFIG_64BIT)
-#define FFS_SCM			0x4UL
-#else
-#define IO_URING_SCM_ALL
-#define FFS_SCM			0x0UL
-#endif
-#define FFS_MASK		~(FFS_NOWAIT|FFS_ISREG|FFS_SCM)
+#define FFS_MASK		~(FFS_NOWAIT|FFS_ISREG)
 
 bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files);
 void io_free_file_tables(struct io_file_table *table);
@@ -38,6 +25,7 @@ unsigned int io_file_get_flags(struct file *file);
 
 static inline void io_file_bitmap_clear(struct io_file_table *table, int bit)
 {
+	WARN_ON_ONCE(!test_bit(bit, table->bitmap));
 	__clear_bit(bit, table->bitmap);
 	table->alloc_hint = bit;
 }

io_uring/io-wq.c

@@ -1164,10 +1164,10 @@ struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data)
 		wqe = kzalloc_node(sizeof(struct io_wqe), GFP_KERNEL, alloc_node);
 		if (!wqe)
 			goto err;
+		wq->wqes[node] = wqe;
 		if (!alloc_cpumask_var(&wqe->cpu_mask, GFP_KERNEL))
 			goto err;
 		cpumask_copy(wqe->cpu_mask, cpumask_of_node(node));
-		wq->wqes[node] = wqe;
 		wqe->node = alloc_node;
 		wqe->acct[IO_WQ_ACCT_BOUND].max_workers = bounded;
 		wqe->acct[IO_WQ_ACCT_UNBOUND].max_workers =

io_uring/io_uring.c

@@ -1587,8 +1587,6 @@ unsigned int io_file_get_flags(struct file *file)
 		res |= FFS_ISREG;
 	if (__io_file_supports_nowait(file, mode))
 		res |= FFS_NOWAIT;
-	if (io_file_need_scm(file))
-		res |= FFS_SCM;
 	return res;
 }
 
@@ -1860,7 +1858,6 @@ inline struct file *io_file_get_fixed(struct io_kiocb *req, int fd,
 	/* mask in overlapping REQ_F and FFS bits */
 	req->flags |= (file_ptr << REQ_F_SUPPORT_NOWAIT_BIT);
 	io_req_set_rsrc_node(req, ctx, 0);
-	WARN_ON_ONCE(file && !test_bit(fd, ctx->file_table.bitmap));
 out:
 	io_ring_submit_unlock(ctx, issue_flags);
 	return file;
@@ -2563,18 +2560,14 @@ static int io_eventfd_unregister(struct io_ring_ctx *ctx)
 
 static void io_req_caches_free(struct io_ring_ctx *ctx)
 {
-	struct io_submit_state *state = &ctx->submit_state;
 	int nr = 0;
 
 	mutex_lock(&ctx->uring_lock);
-	io_flush_cached_locked_reqs(ctx, state);
+	io_flush_cached_locked_reqs(ctx, &ctx->submit_state);
 
 	while (!io_req_cache_empty(ctx)) {
-		struct io_wq_work_node *node;
-		struct io_kiocb *req;
+		struct io_kiocb *req = io_alloc_req(ctx);
 
-		node = wq_stack_extract(&state->free_list);
-		req = container_of(node, struct io_kiocb, comp_list);
 		kmem_cache_free(req_cachep, req);
 		nr++;
 	}
@@ -2811,15 +2804,12 @@ static __cold void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
 		io_poll_remove_all(ctx, NULL, true);
 	mutex_unlock(&ctx->uring_lock);
 
-	/* failed during ring init, it couldn't have issued any requests */
-	if (ctx->rings) {
+	/*
+	 * If we failed setting up the ctx, we might not have any rings
+	 * and therefore did not submit any requests
+	 */
+	if (ctx->rings)
 		io_kill_timeouts(ctx, NULL, true);
-		/* if we failed setting up the ctx, we might not have any rings */
-		io_iopoll_try_reap_events(ctx);
-		/* drop cached put refs after potentially doing completions */
-		if (current->io_uring)
-			io_uring_drop_tctx_refs(current);
-	}
 
 	INIT_WORK(&ctx->exit_work, io_ring_exit_work);
 	/*

io_uring/msg_ring.c

@@ -95,6 +95,9 @@ static int io_msg_send_fd(struct io_kiocb *req, unsigned int issue_flags)
 
 	msg->src_fd = array_index_nospec(msg->src_fd, ctx->nr_user_files);
 	file_ptr = io_fixed_file_slot(&ctx->file_table, msg->src_fd)->file_ptr;
+	if (!file_ptr)
+		goto out_unlock;
+
 	src_file = (struct file *) (file_ptr & FFS_MASK);
 	get_file(src_file);
 

io_uring/rsrc.c

@@ -757,20 +757,17 @@ int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx,
 
 void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
 {
-#if !defined(IO_URING_SCM_ALL)
 	int i;
 
 	for (i = 0; i < ctx->nr_user_files; i++) {
 		struct file *file = io_file_from_index(&ctx->file_table, i);
 
-		if (!file)
-			continue;
-		if (io_fixed_file_slot(&ctx->file_table, i)->file_ptr & FFS_SCM)
+		/* skip scm accounted files, they'll be freed by ->ring_sock */
+		if (!file || io_file_need_scm(file))
 			continue;
 		io_file_bitmap_clear(&ctx->file_table, i);
 		fput(file);
 	}
-#endif
 
 #if defined(CONFIG_UNIX)
 	if (ctx->ring_sock) {

io_uring/rsrc.h

@@ -82,11 +82,7 @@ int __io_scm_file_account(struct io_ring_ctx *ctx, struct file *file);
 #if defined(CONFIG_UNIX)
 static inline bool io_file_need_scm(struct file *filp)
 {
-#if defined(IO_URING_SCM_ALL)
-	return true;
-#else
 	return !!unix_get_socket(filp);
-#endif
 }
 #else
 static inline bool io_file_need_scm(struct file *filp)

io_uring/rw.c

@@ -242,8 +242,6 @@ static void io_req_io_end(struct io_kiocb *req)
 {
 	struct io_rw *rw = io_kiocb_to_cmd(req, struct io_rw);
 
-	WARN_ON(!in_task());
-
 	if (rw->kiocb.ki_flags & IOCB_WRITE) {
 		kiocb_end_write(req);
 		fsnotify_modify(req->file);