linux-kernel - [PATCH v2 20/29] cifs: avoid pointless cred reference count bump

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Message-Id: <20241125-work-cred-v2-20-68b9d38bb5b2@kernel.org>
Date: Mon, 25 Nov 2024 15:10:16 +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 20/29] cifs: avoid pointless cred reference count bump

During module init root_cred will be allocated with its own reference
which is only destroyed during module exit.

Signed-off-by: Christian Brauner <brauner@...nel.org>
---
 fs/smb/client/cifsacl.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/smb/client/cifsacl.c b/fs/smb/client/cifsacl.c
index 4cb3547f4934143c69a4dac3b9f957d75ae20e0b..1d294d53f662479c0323d5f5a645478c6f590062 100644
--- a/fs/smb/client/cifsacl.c
+++ b/fs/smb/client/cifsacl.c
@@ -292,7 +292,7 @@ id_to_sid(unsigned int cid, uint sidtype, struct smb_sid *ssid)
 		return -EINVAL;
 
 	rc = 0;
-	saved_cred = override_creds(get_new_cred(root_cred));
+	saved_cred = override_creds(root_cred);
 	sidkey = request_key(&cifs_idmap_key_type, desc, "");
 	if (IS_ERR(sidkey)) {
 		rc = -EINVAL;
@@ -327,7 +327,7 @@ id_to_sid(unsigned int cid, uint sidtype, struct smb_sid *ssid)
 out_key_put:
 	key_put(sidkey);
 out_revert_creds:
-	put_cred(revert_creds(saved_cred));
+	revert_creds(saved_cred);
 	return rc;
 
 invalidate_key:
@@ -398,7 +398,7 @@ sid_to_id(struct cifs_sb_info *cifs_sb, struct smb_sid *psid,
 	if (!sidstr)
 		return -ENOMEM;
 
-	saved_cred = override_creds(get_new_cred(root_cred));
+	saved_cred = override_creds(root_cred);
 	sidkey = request_key(&cifs_idmap_key_type, sidstr, "");
 	if (IS_ERR(sidkey)) {
 		cifs_dbg(FYI, "%s: Can't map SID %s to a %cid\n",
@@ -438,7 +438,7 @@ sid_to_id(struct cifs_sb_info *cifs_sb, struct smb_sid *psid,
 out_key_put:
 	key_put(sidkey);
 out_revert_creds:
-	put_cred(revert_creds(saved_cred));
+	revert_creds(saved_cred);
 	kfree(sidstr);
 
 	/*

-- 
2.45.2