smb: client: fix UAF in async decryption (ba89c742) · Commits · EulixOS / Software / Kernel

fs/cifs/smb2ops.c

+29 −20

Original line number	Diff line number	Diff line
		@@ -4287,7 +4287,7 @@ smb2_get_enc_key(struct TCP_Server_Info server, __u64 ses_id, int enc, u8 key)
		*/
		static int
		crypt_message(struct TCP_Server_Info *server, int num_rqst,
		struct smb_rqst *rqst, int enc)
		struct smb_rqst rqst, int enc, struct crypto_aead tfm)
		{
		struct smb2_transform_hdr *tr_hdr =
		(struct smb2_transform_hdr *)rqst[0].rq_iov[0].iov_base;
		@@ -4298,8 +4298,6 @@ crypt_message(struct TCP_Server_Info *server, int num_rqst,
		u8 key[SMB3_ENC_DEC_KEY_SIZE];
		struct aead_request *req;
		u8 *iv;
		DECLARE_CRYPTO_WAIT(wait);
		struct crypto_aead *tfm;
		unsigned int crypt_len = le32_to_cpu(tr_hdr->OriginalMessageSize);
		void *creq;

		@@ -4310,15 +4308,6 @@ crypt_message(struct TCP_Server_Info *server, int num_rqst,
		return rc;
		}

		rc = smb3_crypto_aead_allocate(server);
		if (rc) {
		cifs_server_dbg(VFS, "%s: crypto alloc failed\n", __func__);
		return rc;
		}

		tfm = enc ? server->secmech.ccmaesencrypt :
		server->secmech.ccmaesdecrypt;

		if ((server->cipher_type == SMB2_ENCRYPTION_AES256_CCM) \|\|
		(server->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
		rc = crypto_aead_setkey(tfm, key, SMB3_GCM256_CRYPTKEY_SIZE);
		@@ -4357,11 +4346,7 @@ crypt_message(struct TCP_Server_Info *server, int num_rqst,
		aead_request_set_crypt(req, sg, sg, crypt_len, iv);
		aead_request_set_ad(req, assoc_data_len);

		aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
		crypto_req_done, &wait);

		rc = crypto_wait_req(enc ? crypto_aead_encrypt(req)
		: crypto_aead_decrypt(req), &wait);
		rc = enc ? crypto_aead_encrypt(req) : crypto_aead_decrypt(req);

		if (!rc && enc)
		memcpy(&tr_hdr->Signature, sign, SMB2_SIGNATURE_SIZE);
		@@ -4450,7 +4435,8 @@ smb3_init_transform_rq(struct TCP_Server_Info *server, int num_rqst,
		/* fill the 1st iov with a transform header */
		fill_transform_hdr(tr_hdr, orig_len, old_rq, server->cipher_type);

		rc = crypt_message(server, num_rqst, new_rq, 1);
		rc = crypt_message(server, num_rqst, new_rq, 1,
		server->secmech.ccmaesencrypt);
		cifs_dbg(FYI, "Encrypt message returned %d\n", rc);
		if (rc)
		goto err_free;
		@@ -4476,8 +4462,9 @@ decrypt_raw_data(struct TCP_Server_Info server, char buf,
		unsigned int npages, unsigned int page_data_size,
		bool is_offloaded)
		{
		struct kvec iov[2];
		struct crypto_aead *tfm;
		struct smb_rqst rqst = {NULL};
		struct kvec iov[2];
		int rc;

		iov[0].iov_base = buf;
		@@ -4492,9 +4479,31 @@ decrypt_raw_data(struct TCP_Server_Info server, char buf,
		rqst.rq_pagesz = PAGE_SIZE;
		rqst.rq_tailsz = (page_data_size % PAGE_SIZE) ? : PAGE_SIZE;

		rc = crypt_message(server, 1, &rqst, 0);
		if (is_offloaded) {
		if ((server->cipher_type == SMB2_ENCRYPTION_AES128_GCM) \|\|
		(server->cipher_type == SMB2_ENCRYPTION_AES256_GCM))
		tfm = crypto_alloc_aead("gcm(aes)", 0, 0);
		else
		tfm = crypto_alloc_aead("ccm(aes)", 0, 0);
		if (IS_ERR(tfm)) {
		rc = PTR_ERR(tfm);
		cifs_server_dbg(VFS, "%s: Failed alloc decrypt TFM, rc=%d\n", __func__, rc);

		return rc;
		}
		} else {
		if (unlikely(!server->secmech.ccmaesdecrypt))
		return -EIO;

		tfm = server->secmech.ccmaesdecrypt;
		}

		rc = crypt_message(server, 1, &rqst, 0, tfm);
		cifs_dbg(FYI, "Decrypt message returned %d\n", rc);

		if (is_offloaded)
		crypto_free_aead(tfm);

		if (rc)
		return rc;

fs/cifs/smb2pdu.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -998,6 +998,12 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
		else
		cifs_server_dbg(VFS, "Missing expected negotiate contexts\n");
		}

		if (server->cipher_type && !rc) {
		rc = smb3_crypto_aead_allocate(server);
		if (rc)
		cifs_server_dbg(VFS, "%s: crypto alloc failed, rc=%d\n", __func__, rc);
		}
		neg_exit:
		free_rsp_buf(resp_buftype, rsp);
		return rc;