Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6

Pull CIFS/SMB3 fixes from Steve French:
 "Various CIFS/SMB3 fixes, most for stable"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Fix a possible invalid memory access in smb2_query_symlink()
  fs/cifs: make share unaccessible at root level mountable
  cifs: fix crash due to race in hmac(md5) handling
  cifs: unbreak TCP session reuse
  cifs: Check for existing directory when opening file with O_CREAT
  Add MF-Symlinks support for SMB 2.0

1 files changed, 10 insertions, 6 deletions

diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index 6aeb8d4616a4..8347c90cf483 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -743,24 +743,26 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
 
 	memcpy(ses->auth_key.response + baselen, tiblob, tilen);
 
+	mutex_lock(&ses->server->srv_mutex);
+
 	rc = crypto_hmacmd5_alloc(ses->server);
 	if (rc) {
 		cifs_dbg(VFS, "could not crypto alloc hmacmd5 rc %d\n", rc);
-		goto setup_ntlmv2_rsp_ret;
+		goto unlock;
 	}
 
 	/* calculate ntlmv2_hash */
 	rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
 	if (rc) {
 		cifs_dbg(VFS, "could not get v2 hash rc %d\n", rc);
-		goto setup_ntlmv2_rsp_ret;
+		goto unlock;
 	}
 
 	/* calculate first part of the client response (CR1) */
 	rc = CalcNTLMv2_response(ses, ntlmv2_hash);
 	if (rc) {
 		cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
-		goto setup_ntlmv2_rsp_ret;
+		goto unlock;
 	}
 
 	/* now calculate the session key for NTLMv2 */
@@ -769,13 +771,13 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
 	if (rc) {
 		cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
 			 __func__);
-		goto setup_ntlmv2_rsp_ret;
+		goto unlock;
 	}
 
 	rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
 	if (rc) {
 		cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
-		goto setup_ntlmv2_rsp_ret;
+		goto unlock;
 	}
 
 	rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
@@ -783,7 +785,7 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
 		CIFS_HMAC_MD5_HASH_SIZE);
 	if (rc) {
 		cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
-		goto setup_ntlmv2_rsp_ret;
+		goto unlock;
 	}
 
 	rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
@@ -791,6 +793,8 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
 	if (rc)
 		cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 
+unlock:
+	mutex_unlock(&ses->server->srv_mutex);
 setup_ntlmv2_rsp_ret:
 	kfree(tiblob);