From: Steve French <smfrench@gmail.com>
To: CIFS <linux-cifs@vger.kernel.org>
Cc: linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: [PATCH][CIFS] Use FS_RENAME_DOES_D_MOVE to minimize races in rename
Date: Wed, 26 Feb 2020 00:35:51 -0600 [thread overview]
Message-ID: <CAH2r5mt0=WRC2SgG6UZmZ32PbjZrcK4N_sZ9=WcSEar1utTmCw@mail.gmail.com> (raw)
[-- Attachment #1: Type: text/plain, Size: 110 bytes --]
Should be safer to do the dentry move immediately after the rename
rather than later.
--
Thanks,
Steve
[-- Attachment #2: 0001-cifs-do-d_move-in-rename.patch --]
[-- Type: text/x-patch, Size: 1415 bytes --]
From c1bc75178780665716ad14b8c40a8d8e58d0f3e3 Mon Sep 17 00:00:00 2001
From: Steve French <stfrench@microsoft.com>
Date: Tue, 25 Feb 2020 18:08:54 -0600
Subject: [PATCH] cifs: do d_move in rename
It is safer to do the d_move closer to the rename to
avoid races.
Signed-off-by: Steve French <stfrench@microsoft.com>
---
fs/cifs/cifsfs.c | 4 ++--
fs/cifs/inode.c | 2 ++
2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index fa77fe5258b0..94e3ed4850b5 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -1018,7 +1018,7 @@ struct file_system_type cifs_fs_type = {
.name = "cifs",
.mount = cifs_do_mount,
.kill_sb = cifs_kill_sb,
- /* .fs_flags */
+ .fs_flags = FS_RENAME_DOES_D_MOVE,
};
MODULE_ALIAS_FS("cifs");
@@ -1027,7 +1027,7 @@ static struct file_system_type smb3_fs_type = {
.name = "smb3",
.mount = smb3_do_mount,
.kill_sb = cifs_kill_sb,
- /* .fs_flags */
+ .fs_flags = FS_RENAME_DOES_D_MOVE,
};
MODULE_ALIAS_FS("smb3");
MODULE_ALIAS("smb3");
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 6543465595f6..7bb7ff110dc6 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1835,6 +1835,8 @@ cifs_do_rename(const unsigned int xid, struct dentry *from_dentry,
CIFSSMBClose(xid, tcon, fid.netfid);
}
do_rename_exit:
+ if (rc == 0)
+ d_move(from_dentry, to_dentry);
cifs_put_tlink(tlink);
return rc;
}
--
2.20.1
next reply other threads:[~2020-02-26 6:36 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-26 6:35 Steve French [this message]
2020-02-26 9:22 ` [PATCH][CIFS] Use FS_RENAME_DOES_D_MOVE to minimize races in rename Amir Goldstein
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