linux-kernel - [PATCH v2 17/29] open: avoid pointless cred reference count bump

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Message-Id: <20241125-work-cred-v2-17-68b9d38bb5b2@kernel.org>
Date: Mon, 25 Nov 2024 15:10:13 +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 17/29] open: avoid pointless cred reference count bump

The code already got rid of the extra reference count from the old
version of override_creds().

Signed-off-by: Christian Brauner <brauner@...nel.org>
---
 fs/open.c | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/fs/open.c b/fs/open.c
index 0a5cd8e74fb9bb4cc484d84096c6123b21acbf16..ffcfef67ac864c8ddaf9719cbc2762d5575597f3 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -402,7 +402,6 @@ static bool access_need_override_creds(int flags)
 
 static const struct cred *access_override_creds(void)
 {
-	const struct cred *old_cred;
 	struct cred *override_cred;
 
 	override_cred = prepare_creds();
@@ -447,13 +446,7 @@ static const struct cred *access_override_creds(void)
 	 * freeing.
 	 */
 	override_cred->non_rcu = 1;
-
-	old_cred = override_creds(get_new_cred(override_cred));
-
-	/* override_cred() gets its own ref */
-	put_cred(override_cred);
-
-	return old_cred;
+	return override_creds(override_cred);
 }
 
 static long do_faccessat(int dfd, const char __user *filename, int mode, int flags)

-- 
2.45.2