linux-kernel - [PATCH 22/26] io_uring: avoid pointless cred reference count bump

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Message-ID: <20241124-work-cred-v1-22-f352241c3970@kernel.org>
Date: Sun, 24 Nov 2024 14:44:08 +0100
From: Christian Brauner <brauner@...nel.org>
To: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Christian Brauner <brauner@...nel.org>,
	Amir Goldstein <amir73il@...il.com>,
	Miklos Szeredi <miklos@...redi.hu>,
	linux-kernel@...r.kernel.org,
	linux-fsdevel@...r.kernel.org
Subject: [PATCH 22/26] io_uring: avoid pointless cred reference count bump

No need for the extra reference count bump.

Signed-off-by: Christian Brauner <brauner@...nel.org>
---
 io_uring/io_uring.c | 4 ++--
 io_uring/sqpoll.c   | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index ad4d8e94a8665cf5f3e9ea0fd9bc6c03a03cc48f..8012933998837ddcef45c14f1dfe543947a9eaec 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -1704,7 +1704,7 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
 		return -EBADF;
 
 	if (unlikely((req->flags & REQ_F_CREDS) && req->creds != current_cred()))
-		creds = override_creds(get_new_cred(req->creds));
+		creds = override_creds(req->creds);
 
 	if (!def->audit_skip)
 		audit_uring_entry(req->opcode);
@@ -1715,7 +1715,7 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
 		audit_uring_exit(!ret, ret);
 
 	if (creds)
-		put_cred(revert_creds(creds));
+		revert_creds(creds);
 
 	if (ret == IOU_OK) {
 		if (issue_flags & IO_URING_F_COMPLETE_DEFER)
diff --git a/io_uring/sqpoll.c b/io_uring/sqpoll.c
index 1ca96347433695de1eb0e3bec7c6da4299e9ceb0..6df5e649c413e39e36db6cde2a8c6745e533bea9 100644
--- a/io_uring/sqpoll.c
+++ b/io_uring/sqpoll.c
@@ -174,7 +174,7 @@ static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
 		const struct cred *creds = NULL;
 
 		if (ctx->sq_creds != current_cred())
-			creds = override_creds(get_new_cred(ctx->sq_creds));
+			creds = override_creds(ctx->sq_creds);
 
 		mutex_lock(&ctx->uring_lock);
 		if (!wq_list_empty(&ctx->iopoll_list))
@@ -192,7 +192,7 @@ static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
 		if (to_submit && wq_has_sleeper(&ctx->sqo_sq_wait))
 			wake_up(&ctx->sqo_sq_wait);
 		if (creds)
-			put_cred(revert_creds(creds));
+			revert_creds(creds);
 	}
 
 	return ret;

-- 
2.45.2