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From:   Qiujun Huang <hqjagain@gmail.com>
Date:   Wed, 4 Mar 2020 07:13:27 +0800
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Subject: Re: [PATCH] fs/cifs/cifsacl: fix sid_to_id
To:     Steve French <smfrench@gmail.com>
Cc:     Steve French <sfrench@samba.org>,
        CIFS <linux-cifs@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Wed, Mar 4, 2020 at 4:13 AM Steve French <smfrench@gmail.com> wrote:
>
> Doesn't rc = 0 have to be set earlier (preferably in the declaration
> on line 345)?
>
> since line 392 does
>             goto got_valid_id;
> which appears to leave rc unitialized with your change
>
ok, I noticed that fall back to using the mnt_uid/mnt_gid.

Should we remove the variable 'rc'. It is set but not used. And I was
confused last time. (:

diff --git a/fs/cifs/cifsacl.c b/fs/cifs/cifsacl.c
index 716574a..1cf3916 100644
--- a/fs/cifs/cifsacl.c
+++ b/fs/cifs/cifsacl.c
@@ -342,7 +342,6 @@
 sid_to_id(struct cifs_sb_info *cifs_sb, struct cifs_sid *psid,
                struct cifs_fattr *fattr, uint sidtype)
 {
-       int rc;
        struct key *sidkey;
        char *sidstr;
        const struct cred *saved_cred;
@@ -403,7 +402,6 @@
        saved_cred = override_creds(root_cred);
        sidkey = request_key(&cifs_idmap_key_type, sidstr, "");
        if (IS_ERR(sidkey)) {
-               rc = -EINVAL;
                cifs_dbg(FYI, "%s: Can't map SID %s to a %cid\n",
                         __func__, sidstr, sidtype == SIDOWNER ? 'u' : 'g');
                goto out_revert_creds;
@@ -416,7 +414,6 @@
         */
        BUILD_BUG_ON(sizeof(uid_t) != sizeof(gid_t));
        if (sidkey->datalen != sizeof(uid_t)) {
-               rc = -EIO;
                cifs_dbg(FYI, "%s: Downcall contained malformed key
(datalen=%hu)\n",
                         __func__, sidkey->datalen);
                key_invalidate(sidkey);