From 04febabcf55beeffb8794a0d8c539e571bd2ae29 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Tue, 17 Jan 2012 16:09:15 -0500 Subject: [PATCH] cifs: sanitize username handling Currently, it's not very clear whether you're allowed to have a NULL vol->username or ses->user_name. Some places check for it and some don't. Make it clear that a NULL pointer is OK in these fields, and ensure that all the callers check for that. Signed-off-by: Jeff Layton Signed-off-by: Steve French --- fs/cifs/cifs_spnego.c | 10 +++++++--- fs/cifs/cifsencrypt.c | 11 ++++++++--- fs/cifs/connect.c | 19 ++++++++++++------- 3 files changed, 27 insertions(+), 13 deletions(-) diff --git a/fs/cifs/cifs_spnego.c b/fs/cifs/cifs_spnego.c index 2272fd5fe5b7..e622863b292f 100644 --- a/fs/cifs/cifs_spnego.c +++ b/fs/cifs/cifs_spnego.c @@ -113,9 +113,11 @@ cifs_get_spnego_key(struct cifs_ses *sesInfo) MAX_MECH_STR_LEN + UID_KEY_LEN + (sizeof(uid_t) * 2) + CREDUID_KEY_LEN + (sizeof(uid_t) * 2) + - USER_KEY_LEN + strlen(sesInfo->user_name) + PID_KEY_LEN + (sizeof(pid_t) * 2) + 1; + if (sesInfo->user_name) + desc_len += USER_KEY_LEN + strlen(sesInfo->user_name); + spnego_key = ERR_PTR(-ENOMEM); description = kzalloc(desc_len, GFP_KERNEL); if (description == NULL) @@ -152,8 +154,10 @@ cifs_get_spnego_key(struct cifs_ses *sesInfo) dp = description + strlen(description); sprintf(dp, ";creduid=0x%x", sesInfo->cred_uid); - dp = description + strlen(description); - sprintf(dp, ";user=%s", sesInfo->user_name); + if (sesInfo->user_name) { + dp = description + strlen(description); + sprintf(dp, ";user=%s", sesInfo->user_name); + } dp = description + strlen(description); sprintf(dp, ";pid=0x%x", current->pid); diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c index 5d9b9acc5fce..bce99e6a4950 100644 --- a/fs/cifs/cifsencrypt.c +++ b/fs/cifs/cifsencrypt.c @@ -420,15 +420,20 @@ static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash, } /* convert ses->user_name to unicode and uppercase */ - len = strlen(ses->user_name); + len = ses->user_name ? strlen(ses->user_name) : 0; user = kmalloc(2 + (len * 2), GFP_KERNEL); if (user == NULL) { cERROR(1, "calc_ntlmv2_hash: user mem alloc failure\n"); rc = -ENOMEM; return rc; } - len = cifs_strtoUCS((__le16 *)user, ses->user_name, len, nls_cp); - UniStrupr(user); + + if (len) { + len = cifs_strtoUCS((__le16 *)user, ses->user_name, len, nls_cp); + UniStrupr(user); + } else { + memset(user, '\0', 2); + } rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash, (char *)user, 2 * len); diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index a66dcb52988c..b952a21e917b 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -1997,10 +1997,16 @@ static int match_session(struct cifs_ses *ses, struct smb_vol *vol) return 0; break; default: + /* NULL username means anonymous session */ + if (ses->user_name == NULL) { + if (!vol->nullauth) + return 0; + break; + } + /* anything else takes username/password */ - if (ses->user_name == NULL) - return 0; - if (strncmp(ses->user_name, vol->username, + if (strncmp(ses->user_name, + vol->username ? vol->username : "", MAX_USERNAME_SIZE)) return 0; if (strlen(vol->username) != 0 && @@ -3167,10 +3173,9 @@ cifs_setup_volume_info(struct smb_vol *volume_info, char *mount_data, return -EINVAL; if (volume_info->nullauth) { - cFYI(1, "null user"); - volume_info->username = kzalloc(1, GFP_KERNEL); - if (volume_info->username == NULL) - return -ENOMEM; + cFYI(1, "Anonymous login"); + kfree(volume_info->username); + volume_info->username = NULL; } else if (volume_info->username) { /* BB fixme parse for domain name here */ cFYI(1, "Username: %s", volume_info->username); -- 2.20.1