From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 10B4D2BD01B for ; Thu, 14 May 2026 15:53:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778774027; cv=none; b=m14FkHl5s2WvkrW7sX47eYnEVw9kpsg0Go0rs7f01Fr8H/hz7ot0d5Tjaf0nsTdYgjZUMLjrrrLGAaefvroBlb6L9rnaegdRQ6L80UGJLNdAT5rHLw6fsXOK28vlXcR4u2vVAsUO4bZvXOnxIZYchYj/VAfMu87y4xf9/zW2NAg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778774027; c=relaxed/simple; bh=GDnKBLTIHNfhQvkyPaYMax+3j4vh8+/FPacfR3pzm8c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=m+WXJnKt2vtaBjhPKaL9VB6FRJxPmx6RcQzV4BDd5JbM8Tb4vN1s1tkZBFw/AcvpQ8y2phSSl3oA0fZFp/6wkK5oVxjeTCz5WGTwWVVZhnak+90aC46/8UG5A1XqQb+9FcWw6BxR+p+BxoX/qayoSUMzu8xdfRMxBmDmNNXO4BE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=bCcB2uo4; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="bCcB2uo4" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1778774024; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=DcJVL1sjxm91ORiDu6NYtWQsOgCvGFP1+jBk7ZmKqoU=; b=bCcB2uo4T6U6XPmutMz6AAOwRcQ+vT7a8FQlblsKNClY7mkEkPdWNKqA3VEDEbXQWhWC30 mBpk5jTEmxCD1MLSw85NxTNNwkT9kqAUKi7SeNNXRFjbxNfN3RbeYp5000GJinjSaPC83b r8EDldhewghVIZ682QvCmuQAyRtMtmU= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-343-WDkZ_RC9Oz2K2f_jIHuVOQ-1; Thu, 14 May 2026 11:53:39 -0400 X-MC-Unique: WDkZ_RC9Oz2K2f_jIHuVOQ-1 X-Mimecast-MFC-AGG-ID: WDkZ_RC9Oz2K2f_jIHuVOQ_1778774016 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id A6B5419560B1; Thu, 14 May 2026 15:53:36 +0000 (UTC) Received: from warthog.procyon.org.com (unknown [10.44.48.83]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 8AFD31955F2D; Thu, 14 May 2026 15:53:32 +0000 (UTC) From: David Howells To: netdev@vger.kernel.org Cc: David Howells , Hyunwoo Kim , Marc Dionne , Jakub Kicinski , "David S. Miller" , Eric Dumazet , Paolo Abeni , Simon Horman , linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org, Jeffrey Altman , Jiayuan Chen , stable@kernel.org Subject: [PATCH net v3 4/4] rxrpc: Fix RESPONSE packet verification to extract skb to a linear buffer Date: Thu, 14 May 2026 16:53:02 +0100 Message-ID: <20260514155304.2249591-5-dhowells@redhat.com> In-Reply-To: <20260514155304.2249591-1-dhowells@redhat.com> References: <20260514155304.2249591-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 This improves the fix for CVE-2026-43500. Fix the verification of RESPONSE packets to avoid the problem of overwriting a RESPONSE packet sent via splice to a local address by extracting the contents of the UDP packet into a kmalloc'd linear buffer rather than decrypting the data in place in the sk_buff (which may corrupt the original buffer). Fixes: 24481a7f5733 ("rxrpc: Fix conn-level packet handling to unshare RESPONSE packets") Reported-by: Hyunwoo Kim Closes: https://lore.kernel.org/r/afKV2zGR6rrelPC7@v4bel/ Signed-off-by: David Howells cc: Marc Dionne cc: Jeffrey Altman cc: Eric Dumazet cc: "David S. Miller" cc: Jakub Kicinski cc: Paolo Abeni cc: Simon Horman cc: Jiayuan Chen cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org cc: stable@kernel.org --- net/rxrpc/ar-internal.h | 7 +-- net/rxrpc/conn_event.c | 32 ++++++-------- net/rxrpc/insecure.c | 5 ++- net/rxrpc/rxgk.c | 96 +++++++++++++---------------------------- net/rxrpc/rxgk_app.c | 46 ++++++++------------ net/rxrpc/rxgk_common.h | 92 +-------------------------------------- net/rxrpc/rxkad.c | 29 +++++-------- 7 files changed, 82 insertions(+), 225 deletions(-) diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h index 783367eea798..98f2165159d7 100644 --- a/net/rxrpc/ar-internal.h +++ b/net/rxrpc/ar-internal.h @@ -307,15 +307,16 @@ struct rxrpc_security { struct sk_buff *challenge); /* verify a response */ - int (*verify_response)(struct rxrpc_connection *, - struct sk_buff *); + int (*verify_response)(struct rxrpc_connection *conn, + struct sk_buff *response_skb, + void *response, unsigned int len); /* clear connection security */ void (*clear)(struct rxrpc_connection *); /* Default ticket -> key decoder */ int (*default_decode_ticket)(struct rxrpc_connection *conn, struct sk_buff *skb, - unsigned int ticket_offset, unsigned int ticket_len, + void *ticket, unsigned int ticket_len, struct key **_key); }; diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c index 442414d90ba1..c96ca615b787 100644 --- a/net/rxrpc/conn_event.c +++ b/net/rxrpc/conn_event.c @@ -243,28 +243,22 @@ static void rxrpc_call_is_secure(struct rxrpc_call *call) static int rxrpc_verify_response(struct rxrpc_connection *conn, struct sk_buff *skb) { + unsigned int len = skb->len - sizeof(struct rxrpc_wire_header); + void *buffer; int ret; - if (skb_cloned(skb) || skb_has_frag_list(skb) || - skb_has_shared_frag(skb)) { - /* Copy the packet if shared so that we can do in-place - * decryption. - */ - struct sk_buff *nskb = skb_copy(skb, GFP_NOFS); - - if (nskb) { - rxrpc_new_skb(nskb, rxrpc_skb_new_unshared); - ret = conn->security->verify_response(conn, nskb); - rxrpc_free_skb(nskb, rxrpc_skb_put_response_copy); - } else { - /* OOM - Drop the packet. */ - rxrpc_see_skb(skb, rxrpc_skb_see_unshare_nomem); - ret = -ENOMEM; - } - } else { - ret = conn->security->verify_response(conn, skb); - } + buffer = kmalloc(len, GFP_NOFS); + if (!buffer) + return -ENOMEM; + + ret = skb_copy_bits(skb, sizeof(struct rxrpc_wire_header), buffer, len); + if (ret < 0) + goto out; + + ret = conn->security->verify_response(conn, skb, buffer, len); +out: + kfree(buffer); return ret; } diff --git a/net/rxrpc/insecure.c b/net/rxrpc/insecure.c index 7a26c6097d03..0b39046bdc61 100644 --- a/net/rxrpc/insecure.c +++ b/net/rxrpc/insecure.c @@ -54,9 +54,10 @@ static int none_sendmsg_respond_to_challenge(struct sk_buff *challenge, } static int none_verify_response(struct rxrpc_connection *conn, - struct sk_buff *skb) + struct sk_buff *response_skb, + void *response, unsigned int len) { - return rxrpc_abort_conn(conn, skb, RX_PROTOCOL_ERROR, -EPROTO, + return rxrpc_abort_conn(conn, response_skb, RX_PROTOCOL_ERROR, -EPROTO, rxrpc_eproto_rxnull_response); } diff --git a/net/rxrpc/rxgk.c b/net/rxrpc/rxgk.c index f81703ee7ac3..a1ee102abae1 100644 --- a/net/rxrpc/rxgk.c +++ b/net/rxrpc/rxgk.c @@ -1084,11 +1084,12 @@ static int rxgk_sendmsg_respond_to_challenge(struct sk_buff *challenge, * unsigned int call_numbers<>; * }; */ -static int rxgk_do_verify_authenticator(struct rxrpc_connection *conn, - const struct krb5_enctype *krb5, - struct sk_buff *skb, - __be32 *p, __be32 *end) +static int rxgk_verify_authenticator(struct rxrpc_connection *conn, + const struct krb5_enctype *krb5, + struct sk_buff *skb, + void *auth, unsigned int auth_len) { + __be32 *p = auth, *end = auth + auth_len; u32 app_len, call_count, level, epoch, cid, i; _enter(""); @@ -1151,37 +1152,6 @@ static int rxgk_do_verify_authenticator(struct rxrpc_connection *conn, return 0; } -/* - * Extract the authenticator and verify it. - */ -static int rxgk_verify_authenticator(struct rxrpc_connection *conn, - const struct krb5_enctype *krb5, - struct sk_buff *skb, - unsigned int auth_offset, unsigned int auth_len) -{ - void *auth; - __be32 *p; - int ret; - - auth = kmalloc(auth_len, GFP_NOFS); - if (!auth) - return -ENOMEM; - - ret = skb_copy_bits(skb, auth_offset, auth, auth_len); - if (ret < 0) { - ret = rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO, - rxgk_abort_resp_short_auth); - goto error; - } - - p = auth; - ret = rxgk_do_verify_authenticator(conn, krb5, skb, p, - p + auth_len / sizeof(*p)); -error: - kfree(auth); - return ret; -} - /* * Verify a response. * @@ -1192,49 +1162,45 @@ static int rxgk_verify_authenticator(struct rxrpc_connection *conn, * }; */ static int rxgk_verify_response(struct rxrpc_connection *conn, - struct sk_buff *skb) + struct sk_buff *skb, + void *buffer, unsigned int len) { const struct krb5_enctype *krb5; struct rxrpc_key_token *token; struct rxrpc_skb_priv *sp = rxrpc_skb(skb); - struct rxgk_response rhdr; + struct rxgk_response *rhdr; struct rxgk_context *gk; struct key *key = NULL; - unsigned int offset = sizeof(struct rxrpc_wire_header); - unsigned int len = skb->len - sizeof(struct rxrpc_wire_header); - unsigned int token_offset, token_len; - unsigned int auth_offset, auth_len; + unsigned int resp_token_len, auth_len; + void *resp_token, *auth; __be32 xauth_len; int ret, ec; _enter("{%d}", conn->debug_id); /* Parse the RXGK_Response object */ - if (sizeof(rhdr) + sizeof(__be32) > len) - goto short_packet; - - if (skb_copy_bits(skb, offset, &rhdr, sizeof(rhdr)) < 0) + if (len < sizeof(*rhdr) + sizeof(__be32)) goto short_packet; - offset += sizeof(rhdr); - len -= sizeof(rhdr); - - token_offset = offset; - token_len = ntohl(rhdr.token_len); - if (token_len > len || - xdr_round_up(token_len) + sizeof(__be32) > len) + rhdr = buffer; + buffer += sizeof(*rhdr); + len -= sizeof(*rhdr); + + resp_token = buffer; + resp_token_len = ntohl(rhdr->token_len); + if (resp_token_len > len || + xdr_round_up(resp_token_len) + sizeof(__be32) > len) goto short_packet; - trace_rxrpc_rx_response(conn, sp->hdr.serial, 0, sp->hdr.cksum, token_len); + trace_rxrpc_rx_response(conn, sp->hdr.serial, 0, sp->hdr.cksum, resp_token_len); - offset += xdr_round_up(token_len); - len -= xdr_round_up(token_len); + buffer += xdr_round_up(resp_token_len); + len -= xdr_round_up(resp_token_len); - if (skb_copy_bits(skb, offset, &xauth_len, sizeof(xauth_len)) < 0) - goto short_packet; - offset += sizeof(xauth_len); + xauth_len = *(__be32 *)buffer; + buffer += sizeof(xauth_len); len -= sizeof(xauth_len); - auth_offset = offset; + auth = buffer; auth_len = ntohl(xauth_len); if (auth_len > len) goto short_packet; @@ -1249,7 +1215,7 @@ static int rxgk_verify_response(struct rxrpc_connection *conn, * to the app to deal with - which might mean a round trip to * userspace. */ - ret = rxgk_extract_token(conn, skb, token_offset, token_len, &key); + ret = rxgk_extract_token(conn, skb, resp_token, resp_token_len, &key); if (ret < 0) goto out; @@ -1263,7 +1229,7 @@ static int rxgk_verify_response(struct rxrpc_connection *conn, */ token = key->payload.data[0]; conn->security_level = token->rxgk->level; - conn->rxgk.start_time = __be64_to_cpu(rhdr.start_time); + conn->rxgk.start_time = __be64_to_cpu(rhdr->start_time); gk = rxgk_generate_transport_key(conn, token->rxgk, sp->hdr.cksum, GFP_NOFS); if (IS_ERR(gk)) { @@ -1273,18 +1239,18 @@ static int rxgk_verify_response(struct rxrpc_connection *conn, krb5 = gk->krb5; - trace_rxrpc_rx_response(conn, sp->hdr.serial, krb5->etype, sp->hdr.cksum, token_len); + trace_rxrpc_rx_response(conn, sp->hdr.serial, krb5->etype, sp->hdr.cksum, + resp_token_len); /* Decrypt, parse and verify the authenticator. */ - ret = rxgk_decrypt_skb(krb5, gk->resp_enc, skb, - &auth_offset, &auth_len, &ec); + ret = rxgk_decrypt(krb5, gk->resp_enc, &auth, &auth_len, &ec); if (ret < 0) { rxrpc_abort_conn(conn, skb, RXGK_SEALEDINCON, ret, rxgk_abort_resp_auth_dec); goto out_gk; } - ret = rxgk_verify_authenticator(conn, krb5, skb, auth_offset, auth_len); + ret = rxgk_verify_authenticator(conn, krb5, skb, auth, auth_len); if (ret < 0) goto out_gk; diff --git a/net/rxrpc/rxgk_app.c b/net/rxrpc/rxgk_app.c index 0ef2a29eb695..200a30064fae 100644 --- a/net/rxrpc/rxgk_app.c +++ b/net/rxrpc/rxgk_app.c @@ -40,7 +40,7 @@ * }; */ int rxgk_yfs_decode_ticket(struct rxrpc_connection *conn, struct sk_buff *skb, - unsigned int ticket_offset, unsigned int ticket_len, + void *buffer, unsigned int ticket_len, struct key **_key) { struct rxrpc_key_token *token; @@ -49,7 +49,7 @@ int rxgk_yfs_decode_ticket(struct rxrpc_connection *conn, struct sk_buff *skb, size_t pre_ticket_len, payload_len; unsigned int klen, enctype; void *payload, *ticket; - __be32 *t, *p, *q, tmp[2]; + __be32 *t, *p, *q, *tmp; int ret; _enter(""); @@ -59,10 +59,7 @@ int rxgk_yfs_decode_ticket(struct rxrpc_connection *conn, struct sk_buff *skb, rxgk_abort_resp_short_yfs_tkt); /* Get the session key length */ - ret = skb_copy_bits(skb, ticket_offset, tmp, sizeof(tmp)); - if (ret < 0) - return rxrpc_abort_conn(conn, skb, RXGK_INCONSISTENCY, -EPROTO, - rxgk_abort_resp_short_yfs_klen); + tmp = buffer; enctype = ntohl(tmp[0]); klen = ntohl(tmp[1]); @@ -84,12 +81,7 @@ int rxgk_yfs_decode_ticket(struct rxrpc_connection *conn, struct sk_buff *skb, * it. */ ticket = payload + pre_ticket_len; - ret = skb_copy_bits(skb, ticket_offset, ticket, ticket_len); - if (ret < 0) { - ret = rxrpc_abort_conn(conn, skb, RXGK_INCONSISTENCY, -EPROTO, - rxgk_abort_resp_short_yfs_tkt); - goto error; - } + memcpy(ticket, buffer, ticket_len); /* Fill out the form header. */ p = payload; @@ -131,7 +123,7 @@ int rxgk_yfs_decode_ticket(struct rxrpc_connection *conn, struct sk_buff *skb, goto error; } - /* Ticket read in with skb_copy_bits above */ + /* Ticket appended above. */ q += xdr_round_up(ticket_len) / 4; if (WARN_ON((unsigned long)q - (unsigned long)payload != payload_len)) { ret = -EIO; @@ -182,14 +174,15 @@ int rxgk_yfs_decode_ticket(struct rxrpc_connection *conn, struct sk_buff *skb, * [tools.ietf.org/html/draft-wilkinson-afs3-rxgk-afs-08 sec 6.1] */ int rxgk_extract_token(struct rxrpc_connection *conn, struct sk_buff *skb, - unsigned int token_offset, unsigned int token_len, + void *token, unsigned int token_len, struct key **_key) { const struct krb5_enctype *krb5; const struct krb5_buffer *server_secret; struct crypto_aead *token_enc = NULL; struct key *server_key; - unsigned int ticket_offset, ticket_len; + unsigned int ticket_len; + void *ticket; u32 kvno, enctype; int ret, ec = 0; @@ -197,24 +190,23 @@ int rxgk_extract_token(struct rxrpc_connection *conn, struct sk_buff *skb, __be32 kvno; __be32 enctype; __be32 token_len; - } container; + } *container; - if (token_len < sizeof(container)) + if (token_len < sizeof(*container)) goto short_packet; /* Decode the RXGK_TokenContainer object. This tells us which server * key we should be using. We can then fetch the key, get the secret * and set up the crypto to extract the token. */ - if (skb_copy_bits(skb, token_offset, &container, sizeof(container)) < 0) - goto short_packet; + container = token; + token += sizeof(*container); - kvno = ntohl(container.kvno); - enctype = ntohl(container.enctype); - ticket_len = ntohl(container.token_len); - ticket_offset = token_offset + sizeof(container); + kvno = ntohl(container->kvno); + enctype = ntohl(container->enctype); + ticket_len = ntohl(container->token_len); - if (ticket_len > xdr_round_down(token_len - sizeof(container))) + if (ticket_len > xdr_round_down(token_len - sizeof(*container))) goto short_packet; _debug("KVNO %u", kvno); @@ -237,8 +229,8 @@ int rxgk_extract_token(struct rxrpc_connection *conn, struct sk_buff *skb, * gain access to K0, from which we can derive the transport key and * thence decode the authenticator. */ - ret = rxgk_decrypt_skb(krb5, token_enc, skb, - &ticket_offset, &ticket_len, &ec); + ticket = token; + ret = rxgk_decrypt(krb5, token_enc, &ticket, &ticket_len, &ec); crypto_free_aead(token_enc); token_enc = NULL; if (ret < 0) { @@ -248,7 +240,7 @@ int rxgk_extract_token(struct rxrpc_connection *conn, struct sk_buff *skb, return ret; } - ret = conn->security->default_decode_ticket(conn, skb, ticket_offset, + ret = conn->security->default_decode_ticket(conn, skb, ticket, ticket_len, _key); if (ret < 0) goto cant_get_token; diff --git a/net/rxrpc/rxgk_common.h b/net/rxrpc/rxgk_common.h index 112b5366ce11..3deed5863f5a 100644 --- a/net/rxrpc/rxgk_common.h +++ b/net/rxrpc/rxgk_common.h @@ -41,10 +41,10 @@ struct rxgk_context { * rxgk_app.c */ int rxgk_yfs_decode_ticket(struct rxrpc_connection *conn, struct sk_buff *skb, - unsigned int ticket_offset, unsigned int ticket_len, + void *ticket, unsigned int ticket_len, struct key **_key); int rxgk_extract_token(struct rxrpc_connection *conn, struct sk_buff *skb, - unsigned int token_offset, unsigned int token_len, + void *token, unsigned int token_len, struct key **_key); /* @@ -61,50 +61,6 @@ int rxgk_set_up_token_cipher(const struct krb5_buffer *server_key, const struct krb5_enctype **_krb5, gfp_t gfp); -/* - * Apply decryption and checksumming functions to part of an skbuff. The - * offset and length are updated to reflect the actual content of the encrypted - * region. - */ -static inline -int rxgk_decrypt_skb(const struct krb5_enctype *krb5, - struct crypto_aead *aead, - struct sk_buff *skb, - unsigned int *_offset, unsigned int *_len, - int *_error_code) -{ - struct scatterlist sg[16]; - size_t offset = 0, len = *_len; - int nr_sg, ret; - - sg_init_table(sg, ARRAY_SIZE(sg)); - nr_sg = skb_to_sgvec(skb, sg, *_offset, len); - if (unlikely(nr_sg < 0)) - return nr_sg; - - ret = crypto_krb5_decrypt(krb5, aead, sg, nr_sg, - &offset, &len); - switch (ret) { - case 0: - *_offset += offset; - *_len = len; - break; - case -EBADMSG: /* Checksum mismatch. */ - case -EPROTO: - *_error_code = RXGK_SEALEDINCON; - break; - case -EMSGSIZE: - *_error_code = RXGK_PACKETSHORT; - break; - case -ENOPKG: /* Would prefer RXGK_BADETYPE, but not available for YFS. */ - default: - *_error_code = RXGK_INCONSISTENCY; - break; - } - - return ret; -} - /* * Apply decryption and checksumming functions a flat data buffer. The data * point and length are updated to reflect the actual content of the encrypted @@ -148,50 +104,6 @@ static inline int rxgk_decrypt(const struct krb5_enctype *krb5, return ret; } -/* - * Check the MIC on a region of an skbuff. The offset and length are updated - * to reflect the actual content of the secure region. - */ -static inline -int rxgk_verify_mic_skb(const struct krb5_enctype *krb5, - struct crypto_shash *shash, - const struct krb5_buffer *metadata, - struct sk_buff *skb, - unsigned int *_offset, unsigned int *_len, - u32 *_error_code) -{ - struct scatterlist sg[16]; - size_t offset = 0, len = *_len; - int nr_sg, ret; - - sg_init_table(sg, ARRAY_SIZE(sg)); - nr_sg = skb_to_sgvec(skb, sg, *_offset, len); - if (unlikely(nr_sg < 0)) - return nr_sg; - - ret = crypto_krb5_verify_mic(krb5, shash, metadata, sg, nr_sg, - &offset, &len); - switch (ret) { - case 0: - *_offset += offset; - *_len = len; - break; - case -EBADMSG: /* Checksum mismatch */ - case -EPROTO: - *_error_code = RXGK_SEALEDINCON; - break; - case -EMSGSIZE: - *_error_code = RXGK_PACKETSHORT; - break; - case -ENOPKG: /* Would prefer RXGK_BADETYPE, but not available for YFS. */ - default: - *_error_code = RXGK_INCONSISTENCY; - break; - } - - return ret; -} - /* * Check the MIC on a flat buffer. The data pointer and length are updated to * reflect the actual content of the secure region. diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c index 075936337836..e970bf3ae78a 100644 --- a/net/rxrpc/rxkad.c +++ b/net/rxrpc/rxkad.c @@ -963,7 +963,6 @@ static int rxkad_decrypt_ticket(struct rxrpc_connection *conn, *_expiry = 0; ASSERT(server_key->payload.data[0] != NULL); - ASSERTCMP((unsigned long) ticket & 7UL, ==, 0); memcpy(&iv, &server_key->payload.data[2], sizeof(iv)); @@ -1112,14 +1111,15 @@ static int rxkad_decrypt_response(struct rxrpc_connection *conn, * verify a response */ static int rxkad_verify_response(struct rxrpc_connection *conn, - struct sk_buff *skb) + struct sk_buff *skb, + void *buffer, unsigned int len) { struct rxkad_response *response; struct rxrpc_skb_priv *sp = rxrpc_skb(skb); struct rxrpc_crypt session_key; struct key *server_key; time64_t expiry; - void *ticket = NULL; + void *ticket; u32 version, kvno, ticket_len, level; __be32 csum; int ret, i; @@ -1142,13 +1142,8 @@ static int rxkad_verify_response(struct rxrpc_connection *conn, } } - ret = -ENOMEM; - response = kzalloc_obj(struct rxkad_response, GFP_NOFS); - if (!response) - goto error; - - if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header), - response, sizeof(*response)) < 0) { + response = buffer; + if (len < sizeof(*response)) { ret = rxrpc_abort_conn(conn, skb, RXKADPACKETSHORT, -EPROTO, rxkad_abort_resp_short); goto error; @@ -1160,6 +1155,9 @@ static int rxkad_verify_response(struct rxrpc_connection *conn, trace_rxrpc_rx_response(conn, sp->hdr.serial, version, kvno, ticket_len); + buffer += sizeof(*response); + len -= sizeof(*response); + if (version != RXKAD_VERSION) { ret = rxrpc_abort_conn(conn, skb, RXKADINCONSISTENCY, -EPROTO, rxkad_abort_resp_version); @@ -1179,13 +1177,8 @@ static int rxkad_verify_response(struct rxrpc_connection *conn, } /* extract the kerberos ticket and decrypt and decode it */ - ret = -ENOMEM; - ticket = kmalloc(ticket_len, GFP_NOFS); - if (!ticket) - goto error; - - if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header) + sizeof(*response), - ticket, ticket_len) < 0) { + ticket = buffer; + if (ticket_len >= len) { ret = rxrpc_abort_conn(conn, skb, RXKADPACKETSHORT, -EPROTO, rxkad_abort_resp_short_tkt); goto error; @@ -1265,8 +1258,6 @@ static int rxkad_verify_response(struct rxrpc_connection *conn, ret = rxrpc_get_server_data_key(conn, &session_key, expiry, kvno); error: - kfree(ticket); - kfree(response); key_put(server_key); _leave(" = %d", ret); return ret;