Patchwork [11/11] cifs: add separate cred_uid field to sesInfo

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Submitter Jeff Layton
Date April 24, 2010, 11:57 a.m.
Message ID <1272110272-20686-12-git-send-email-jlayton@redhat.com>
Download mbox | patch
Permalink /patch/50898/
State New
Headers show

Comments

Jeff Layton - April 24, 2010, 11:57 a.m.
First, do a little cleanup -- remove the unused cifsUidInfo struct.

Right now, there's no clear separation between the uid that owns the
credentials used to do the mount and the overriding owner of the files
on that mount.

Add a separate cred_uid field that is set to the real uid
of the mount user. Unlike the linux_uid, the uid= option does not
override this parameter. The parm is sent to cifs.upcall, which can then
preferentially use the creduid= parm instead of the uid= parm for
finding credentials.

This is not the only way to solve this. We could try to do all of this
in kernel instead by having a module parameter that affects what gets
passed in the uid= field of the upcall. That said, we have a lot more
flexibility to change things in userspace so I think it probably makes
sense to do it this way.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
---
 fs/cifs/cifs_spnego.c |    3 +++
 fs/cifs/cifsglob.h    |   19 ++-----------------
 fs/cifs/connect.c     |    7 +++++--
 3 files changed, 10 insertions(+), 19 deletions(-)

Patch

diff --git a/fs/cifs/cifs_spnego.c b/fs/cifs/cifs_spnego.c
index 379bd7d..6effccf 100644
--- a/fs/cifs/cifs_spnego.c
+++ b/fs/cifs/cifs_spnego.c
@@ -144,6 +144,9 @@  cifs_get_spnego_key(struct cifsSesInfo *sesInfo)
 	sprintf(dp, ";uid=0x%x", sesInfo->linux_uid);
 
 	dp = description + strlen(description);
+	sprintf(dp, ";creduid=0x%x", sesInfo->cred_uid);
+
+	dp = description + strlen(description);
 	sprintf(dp, ";user=%s", sesInfo->userName);
 
 	dp = description + strlen(description);
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index eae6033..57355b1 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -194,28 +194,12 @@  struct TCP_Server_Info {
 };
 
 /*
- * The following is our shortcut to user information.  We surface the uid,
- * and name. We always get the password on the fly in case it
- * has changed. We also hang a list of sessions owned by this user off here.
- */
-struct cifsUidInfo {
-	struct list_head userList;
-	struct list_head sessionList; /* SMB sessions for this user */
-	uid_t linux_uid;
-	char user[MAX_USERNAME_SIZE + 1];	/* ascii name of user */
-	/* BB may need ptr or callback for PAM or WinBind info */
-};
-
-/*
  * Session structure.  One of these for each uid session with a particular host
  */
 struct cifsSesInfo {
 	struct list_head smb_ses_list;
 	struct list_head tcon_list;
 	struct mutex session_mutex;
-#if 0
-	struct cifsUidInfo *uidInfo;	/* pointer to user info */
-#endif
 	struct TCP_Server_Info *server;	/* pointer to server info */
 	int ses_count;		/* reference counter */
 	enum statusEnum status;
@@ -227,7 +211,8 @@  struct cifsSesInfo {
 	char *serverNOS;	/* name of network operating system of server */
 	char *serverDomain;	/* security realm of server */
 	int Suid;		/* remote smb uid  */
-	uid_t linux_uid;        /* local Linux uid */
+	uid_t linux_uid;        /* overriding owner of files on the mount */
+	uid_t cred_uid;		/* owner of credentials */
 	int capabilities;
 	char serverName[SERVER_NAME_LEN_WITH_NULL * 2];	/* BB make bigger for
 				TCP names - will ipv6 and sctp addresses fit? */
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 137a0d1..5bb6eac 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -66,6 +66,7 @@  struct smb_vol {
 	char *iocharset;  /* local code page for mapping to and from Unicode */
 	char source_rfc1001_name[16]; /* netbios name of client */
 	char target_rfc1001_name[16]; /* netbios name of server for Win9x/ME */
+	uid_t cred_uid;
 	uid_t linux_uid;
 	gid_t linux_gid;
 	mode_t file_mode;
@@ -830,7 +831,8 @@  cifs_parse_mount_options(char *options, const char *devname,
 	/* null target name indicates to use *SMBSERVR default called name
 	   if we end up sending RFC1001 session initialize */
 	vol->target_rfc1001_name[0] = 0;
-	vol->linux_uid = current_uid();  /* use current_euid() instead? */
+	vol->cred_uid = current_uid();
+	vol->linux_uid = current_uid();
 	vol->linux_gid = current_gid();
 
 	/* default to only allowing write access to owner of the mount */
@@ -1750,7 +1752,7 @@  cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb_vol *vol)
 		case Kerberos:
 			if (ses->secType != Kerberos)
 				continue;
-			if (vol->linux_uid != ses->linux_uid)
+			if (vol->cred_uid != ses->cred_uid)
 				continue;
 			break;
 		default:
@@ -1866,6 +1868,7 @@  cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb_vol *volume_info)
 		if (ses->domainName)
 			strcpy(ses->domainName, volume_info->domainname);
 	}
+	ses->cred_uid = volume_info->cred_uid;
 	ses->linux_uid = volume_info->linux_uid;
 
 	mutex_lock(&ses->session_mutex);