linux-kernel - [PATCH v2 10/29] aio: avoid pointless cred reference count bump

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Message-Id: <20241125-work-cred-v2-10-68b9d38bb5b2@kernel.org>
Date: Mon, 25 Nov 2024 15:10:06 +0100
From: Christian Brauner <brauner@...nel.org>
To: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Amir Goldstein <amir73il@...il.com>, Miklos Szeredi <miklos@...redi.hu>, 
 Al Viro <viro@...iv.linux.org.uk>, Jens Axboe <axboe@...nel.dk>, 
 linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org, 
 Christian Brauner <brauner@...nel.org>
Subject: [PATCH v2 10/29] aio: avoid pointless cred reference count bump

iocb->fsync.creds already holds a reference count that is stable while
the operation is performed.

Signed-off-by: Christian Brauner <brauner@...nel.org>
---
 fs/aio.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/aio.c b/fs/aio.c
index 5e57dcaed7f1ae1e4b38009b51a665954b31f5bd..50671640b5883f5d20f652e23c4ea3fe04c989f2 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1639,10 +1639,10 @@ static int aio_write(struct kiocb *req, const struct iocb *iocb,
 static void aio_fsync_work(struct work_struct *work)
 {
 	struct aio_kiocb *iocb = container_of(work, struct aio_kiocb, fsync.work);
-	const struct cred *old_cred = override_creds(get_new_cred(iocb->fsync.creds));
+	const struct cred *old_cred = override_creds(iocb->fsync.creds);
 
 	iocb->ki_res.res = vfs_fsync(iocb->fsync.file, iocb->fsync.datasync);
-	put_cred(revert_creds(old_cred));
+	revert_creds(old_cred);
 	put_cred(iocb->fsync.creds);
 	iocb_put(iocb);
 }

-- 
2.45.2