From 39e8db3c860e2678ce5a7d74193925876507c9eb Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Tue, 10 Jan 2023 17:55:20 -0300 Subject: cifs: fix double free on failed kerberos auth If session setup failed with kerberos auth, we ended up freeing cifs_ses::auth_key.response twice in SMB2_auth_kerberos() and sesInfoFree(). Fix this by zeroing out cifs_ses::auth_key.response after freeing it in SMB2_auth_kerberos(). Fixes: a4e430c8c8ba ("cifs: replace kfree() with kfree_sensitive() for sensitive data") Signed-off-by: Paulo Alcantara (SUSE) Acked-by: Ronnie Sahlberg Signed-off-by: Steve French --- fs/cifs/smb2pdu.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'fs/cifs/smb2pdu.c') diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 2c484d47c592..727f16b426be 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -1482,8 +1482,11 @@ SMB2_auth_kerberos(struct SMB2_sess_data *sess_data) out_put_spnego_key: key_invalidate(spnego_key); key_put(spnego_key); - if (rc) + if (rc) { kfree_sensitive(ses->auth_key.response); + ses->auth_key.response = NULL; + ses->auth_key.len = 0; + } out: sess_data->result = rc; sess_data->func = NULL; -- cgit v1.2.3 From 2fe58d977ee05da5bb89ef5dc4f5bf2dc15db46f Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Tue, 10 Jan 2023 20:35:46 -0300 Subject: cifs: fix potential memory leaks in session setup Make sure to free cifs_ses::auth_key.response before allocating it as we might end up leaking memory in reconnect or mounting. Signed-off-by: Paulo Alcantara (SUSE) Signed-off-by: Steve French --- fs/cifs/cifsencrypt.c | 1 + fs/cifs/sess.c | 2 ++ fs/cifs/smb2pdu.c | 1 + 3 files changed, 4 insertions(+) (limited to 'fs/cifs/smb2pdu.c') diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c index 5db73c0f792a..cbc18b4a9cb2 100644 --- a/fs/cifs/cifsencrypt.c +++ b/fs/cifs/cifsencrypt.c @@ -278,6 +278,7 @@ build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp) * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) + * unicode length of a netbios domain name */ + kfree_sensitive(ses->auth_key.response); ses->auth_key.len = size + 2 * dlen; ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL); if (!ses->auth_key.response) { diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c index 0b842a07e157..c47b254f0d1e 100644 --- a/fs/cifs/sess.c +++ b/fs/cifs/sess.c @@ -815,6 +815,7 @@ int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len, return -EINVAL; } if (tilen) { + kfree_sensitive(ses->auth_key.response); ses->auth_key.response = kmemdup(bcc_ptr + tioffset, tilen, GFP_KERNEL); if (!ses->auth_key.response) { @@ -1428,6 +1429,7 @@ sess_auth_kerberos(struct sess_data *sess_data) goto out_put_spnego_key; } + kfree_sensitive(ses->auth_key.response); ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len, GFP_KERNEL); if (!ses->auth_key.response) { diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 727f16b426be..4b71f4a92f76 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -1453,6 +1453,7 @@ SMB2_auth_kerberos(struct SMB2_sess_data *sess_data) /* keep session key if binding */ if (!is_binding) { + kfree_sensitive(ses->auth_key.response); ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len, GFP_KERNEL); if (!ses->auth_key.response) { -- cgit v1.2.3