From 31c9590ae468478fe47dc0f5f0d3562b2f69450e Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Sat, 18 Apr 2020 21:06:23 -0400 Subject: SUNRPC: Add "@len" parameter to gss_unwrap() Refactor: This is a pre-requisite to fixing the client-side ralign computation in gss_unwrap_resp_priv(). The length value is passed in explicitly rather that as the value of buf->len. This will subsequently allow gss_unwrap_kerberos_v1() to compute a slack and align value, instead of computing it in gss_unwrap_resp_priv(). Fixes: 35e77d21baa0 ("SUNRPC: Add rpc_auth::au_ralign field") Signed-off-by: Chuck Lever --- net/sunrpc/auth_gss/auth_gss.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/sunrpc/auth_gss/auth_gss.c') diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c index 25fbd8d9de74..7885f37e3688 100644 --- a/net/sunrpc/auth_gss/auth_gss.c +++ b/net/sunrpc/auth_gss/auth_gss.c @@ -2043,9 +2043,9 @@ gss_unwrap_resp_priv(struct rpc_task *task, struct rpc_cred *cred, offset = (u8 *)(p) - (u8 *)head->iov_base; if (offset + opaque_len > rcv_buf->len) goto unwrap_failed; - rcv_buf->len = offset + opaque_len; - maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf); + maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, + offset + opaque_len, rcv_buf); if (maj_stat == GSS_S_CONTEXT_EXPIRED) clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags); if (maj_stat != GSS_S_COMPLETE) -- cgit v1.2.3 From a7e429a6fa6d612d1dacde96c885dc1bb4a9f400 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Sat, 18 Apr 2020 14:38:19 -0400 Subject: SUNRPC: Fix GSS privacy computation of auth->au_ralign When the au_ralign field was added to gss_unwrap_resp_priv, the wrong calculation was used. Setting au_rslack == au_ralign is probably correct for kerberos_v1 privacy, but kerberos_v2 privacy adds additional GSS data after the clear text RPC message. au_ralign needs to be smaller than au_rslack in that fairly common case. When xdr_buf_trim() is restored to gss_unwrap_kerberos_v2(), it does exactly what I feared it would: it trims off part of the clear text RPC message. However, that's because rpc_prepare_reply_pages() does not set up the rq_rcv_buf's tail correctly because au_ralign is too large. Fixing the au_ralign computation also corrects the alignment of rq_rcv_buf->pages so that the client does not have to shift reply data payloads after they are received. Fixes: 35e77d21baa0 ("SUNRPC: Add rpc_auth::au_ralign field") Signed-off-by: Chuck Lever --- net/sunrpc/auth_gss/auth_gss.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) (limited to 'net/sunrpc/auth_gss/auth_gss.c') diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c index 7885f37e3688..ac5cac0dd24b 100644 --- a/net/sunrpc/auth_gss/auth_gss.c +++ b/net/sunrpc/auth_gss/auth_gss.c @@ -2032,7 +2032,6 @@ gss_unwrap_resp_priv(struct rpc_task *task, struct rpc_cred *cred, struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf; struct kvec *head = rqstp->rq_rcv_buf.head; struct rpc_auth *auth = cred->cr_auth; - unsigned int savedlen = rcv_buf->len; u32 offset, opaque_len, maj_stat; __be32 *p; @@ -2059,10 +2058,9 @@ gss_unwrap_resp_priv(struct rpc_task *task, struct rpc_cred *cred, */ xdr_init_decode(xdr, rcv_buf, p, rqstp); - auth->au_rslack = auth->au_verfsize + 2 + - XDR_QUADLEN(savedlen - rcv_buf->len); - auth->au_ralign = auth->au_verfsize + 2 + - XDR_QUADLEN(savedlen - rcv_buf->len); + auth->au_rslack = auth->au_verfsize + 2 + ctx->gc_gss_ctx->slack; + auth->au_ralign = auth->au_verfsize + 2 + ctx->gc_gss_ctx->align; + return 0; unwrap_failed: trace_rpcgss_unwrap_failed(task); -- cgit v1.2.3