From: Ira Weiny <ira.weiny@intel.com>
Date: Tue, 11 Aug 2020 00:02:58 +0000 (-0700)
Subject: net/tls: Fix kmap usage
X-Git-Tag: v5.7.16~71
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=511406544bcbbc5b7f89ee4f033db549f9a0cc6a;p=thirdparty%2Fkernel%2Fstable.git

net/tls: Fix kmap usage

[ Upstream commit b06c19d9f827f6743122795570bfc0c72db482b0 ]

When MSG_OOB is specified to tls_device_sendpage() the mapped page is
never unmapped.

Hold off mapping the page until after the flags are checked and the page
is actually needed.

Fixes: e8f69799810c ("net/tls: Add generic NIC offload infrastructure")
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index a562ebaaa33c3..0ad8b53a8ca41 100644
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -561,7 +561,7 @@ int tls_device_sendpage(struct sock *sk, struct page *page,
 {
 	struct tls_context *tls_ctx = tls_get_ctx(sk);
 	struct iov_iter	msg_iter;
-	char *kaddr = kmap(page);
+	char *kaddr;
 	struct kvec iov;
 	int rc;
 
@@ -576,6 +576,7 @@ int tls_device_sendpage(struct sock *sk, struct page *page,
 		goto out;
 	}
 
+	kaddr = kmap(page);
 	iov.iov_base = kaddr + offset;
 	iov.iov_len = size;
 	iov_iter_kvec(&msg_iter, WRITE, &iov, 1, size);