SUNRPC: Fix leak of krb5p encode pages

commit 8dae5398ab1ac107b1517e8195ed043d5f422bd0 upstream.

call_encode can be invoked more than once per RPC call. Ensure that
each call to gss_wrap_req_priv does not overwrite pointers to
previously allocated memory.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 21c0aa0..8cb7d81 100644 (file)
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -1768,6 +1768,7 @@ priv_release_snd_buf(struct rpc_rqst *rqstp)
        for (i=0; i < rqstp->rq_enc_pages_num; i++)
                __free_page(rqstp->rq_enc_pages[i]);
        kfree(rqstp->rq_enc_pages);
+       rqstp->rq_release_snd_buf = NULL;
 }
 
 static int
@@ -1776,6 +1777,9 @@ alloc_enc_pages(struct rpc_rqst *rqstp)
        struct xdr_buf *snd_buf = &rqstp->rq_snd_buf;
        int first, last, i;
 
+       if (rqstp->rq_release_snd_buf)
+               rqstp->rq_release_snd_buf(rqstp);
+
        if (snd_buf->page_len == 0) {
                rqstp->rq_enc_pages_num = 0;
                return 0;