linux-kernel - [PATCH] cifs: deadstore delete in deferred files

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210513165323.16593-1-wenhui@gwmail.gwu.edu>
Date:   Thu, 13 May 2021 12:53:23 -0400
From:   wenhuizhang <wenhui@...ail.gwu.edu>
To:     unlisted-recipients:; (no To-header on input)
Cc:     wenhuizhang <wenhui@...ail.gwu.edu>,
        Steve French <sfrench@...ba.org>, linux-cifs@...r.kernel.org,
        samba-technical@...ts.samba.org, linux-kernel@...r.kernel.org
Subject: [PATCH] cifs: deadstore delete in deferred files

Deadstore detected by Lukas Bulwahn's CodeChecker Tool (ELISA group).

line 741 struct cifsInodeInfo *cinode;
line 747 cinode = CIFS_I(d_inode(cfile->dentry));
could be deleted.

cinode on filesystem should not be deleted when files are closed, they are representations of some data fields on a physical disk, thus no further action is required.
The virtual inode on vfs will be handled by vfs automatically, and the denotation is inode, which is different from the cinode.

Signed-off-by: wenhuizhang <wenhui@...ail.gwu.edu>

---
 fs/cifs/misc.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index 524dbdfb7184..801a5300f765 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -738,13 +738,11 @@ void
 cifs_close_all_deferred_files(struct cifs_tcon *tcon)
 {
 	struct cifsFileInfo *cfile;
-	struct cifsInodeInfo *cinode;
 	struct list_head *tmp;
 
 	spin_lock(&tcon->open_file_lock);
 	list_for_each(tmp, &tcon->openFileList) {
 		cfile = list_entry(tmp, struct cifsFileInfo, tlist);
-		cinode = CIFS_I(d_inode(cfile->dentry));
 		if (delayed_work_pending(&cfile->deferred))
 			mod_delayed_work(deferredclose_wq, &cfile->deferred, 0);
 	}
-- 
2.17.1