rxgk_verify_packet_integrity() may get more errors than just -EPROTO from rxgk_verify_mic_skb(). Pretty much anything other than -ENOMEM constitutes an unrecoverable error. In the case of -ENOMEM, we can just drop the packet and wait for a retransmission. Similar happens with rxgk_decrypt_skb() and its callers. Fix rxgk_decrypt_skb() or rxgk_verify_mic_skb() to return a greater variety of abort codes and fix their callers to abort the connection on any error apart from -ENOMEM. Also preclear the variables used to hold the abort code returned from rxgk_decrypt_skb() or rxgk_verify_mic_skb() to eliminate uninitialised variable warnings. Fixes: 9d1d2b59341f ("rxrpc: rxgk: Implement the yfs-rxgk security class (GSSAPI)") Reported-by: Dan Carpenter Closes: https://lists.infradead.org/pipermail/linux-afs/2025-April/009739.html Closes: https://lists.infradead.org/pipermail/linux-afs/2025-April/009740.html Signed-off-by: David Howells cc: Marc Dionne cc: Jakub Kicinski cc: "David S. Miller" cc: Eric Dumazet cc: Paolo Abeni cc: Simon Horman cc: linux-afs@lists.infradead.org cc: netdev@vger.kernel.org --- net/rxrpc/rxgk.c | 18 ++++++++++-------- net/rxrpc/rxgk_app.c | 10 ++++++---- net/rxrpc/rxgk_common.h | 14 ++++++++++++-- 3 files changed, 28 insertions(+), 14 deletions(-) diff --git a/net/rxrpc/rxgk.c b/net/rxrpc/rxgk.c index 1e19c605bcc8..dce5a3d8a964 100644 --- a/net/rxrpc/rxgk.c +++ b/net/rxrpc/rxgk.c @@ -475,7 +475,7 @@ static int rxgk_verify_packet_integrity(struct rxrpc_call *call, struct krb5_buffer metadata; unsigned int offset = sp->offset, len = sp->len; size_t data_offset = 0, data_len = len; - u32 ac; + u32 ac = 0; int ret = -ENOMEM; _enter(""); @@ -499,9 +499,10 @@ static int rxgk_verify_packet_integrity(struct rxrpc_call *call, ret = rxgk_verify_mic_skb(gk->krb5, gk->rx_Kc, &metadata, skb, &offset, &len, &ac); kfree(hdr); - if (ret == -EPROTO) { - rxrpc_abort_eproto(call, skb, ac, - rxgk_abort_1_verify_mic_eproto); + if (ret < 0) { + if (ret != -ENOMEM) + rxrpc_abort_eproto(call, skb, ac, + rxgk_abort_1_verify_mic_eproto); } else { sp->offset = offset; sp->len = len; @@ -524,15 +525,16 @@ static int rxgk_verify_packet_encrypted(struct rxrpc_call *call, struct rxgk_header hdr; unsigned int offset = sp->offset, len = sp->len; int ret; - u32 ac; + u32 ac = 0; _enter(""); ret = rxgk_decrypt_skb(gk->krb5, gk->rx_enc, skb, &offset, &len, &ac); - if (ret == -EPROTO) - rxrpc_abort_eproto(call, skb, ac, rxgk_abort_2_decrypt_eproto); - if (ret < 0) + if (ret < 0) { + if (ret != -ENOMEM) + rxrpc_abort_eproto(call, skb, ac, rxgk_abort_2_decrypt_eproto); goto error; + } if (len < sizeof(hdr)) { ret = rxrpc_abort_eproto(call, skb, RXGK_PACKETSHORT, diff --git a/net/rxrpc/rxgk_app.c b/net/rxrpc/rxgk_app.c index b94b77a1c317..df684b5a8531 100644 --- a/net/rxrpc/rxgk_app.c +++ b/net/rxrpc/rxgk_app.c @@ -187,7 +187,7 @@ int rxgk_extract_token(struct rxrpc_connection *conn, struct sk_buff *skb, struct key *server_key; unsigned int ticket_offset, ticket_len; u32 kvno, enctype; - int ret, ec; + int ret, ec = 0; struct { __be32 kvno; @@ -236,9 +236,11 @@ int rxgk_extract_token(struct rxrpc_connection *conn, struct sk_buff *skb, &ticket_offset, &ticket_len, &ec); crypto_free_aead(token_enc); token_enc = NULL; - if (ret < 0) - return rxrpc_abort_conn(conn, skb, ec, ret, - rxgk_abort_resp_tok_dec); + if (ret < 0) { + if (ret != -ENOMEM) + return rxrpc_abort_conn(conn, skb, ec, ret, + rxgk_abort_resp_tok_dec); + } ret = conn->security->default_decode_ticket(conn, skb, ticket_offset, ticket_len, _key); diff --git a/net/rxrpc/rxgk_common.h b/net/rxrpc/rxgk_common.h index 7370a5655985..80164d89e19c 100644 --- a/net/rxrpc/rxgk_common.h +++ b/net/rxrpc/rxgk_common.h @@ -88,11 +88,16 @@ int rxgk_decrypt_skb(const struct krb5_enctype *krb5, *_offset += offset; *_len = len; break; + case -EBADMSG: /* Checksum mismatch. */ case -EPROTO: - case -EBADMSG: *_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; } @@ -127,11 +132,16 @@ int rxgk_verify_mic_skb(const struct krb5_enctype *krb5, *_offset += offset; *_len = len; break; + case -EBADMSG: /* Checksum mismatch */ case -EPROTO: - case -EBADMSG: *_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; }