2020-08-11 00:03:59

by Ira Weiny

[permalink] [raw]
Subject: [PATCH] net/tls: Fix kmap usage

From: Ira Weiny <[email protected]>

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.

Signed-off-by: Ira Weiny <[email protected]>
---
net/tls/tls_device.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index 0e55f8365ce2..0cbad566f281 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);
--
2.28.0.rc0.12.gb6a658bd00c9


2020-08-11 16:02:47

by Jakub Kicinski

[permalink] [raw]
Subject: Re: [PATCH] net/tls: Fix kmap usage

On Mon, 10 Aug 2020 17:02:58 -0700 [email protected] wrote:
> From: Ira Weiny <[email protected]>
>
> When MSG_OOB is specified to tls_device_sendpage() the mapped page is
> never unmapped.

Nice catch!

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

We could take the kmap/kunmap from under the socket lock, but that'd
perhaps be more code reshuffling than we need in a fix.

Fixes: e8f69799810c ("net/tls: Add generic NIC offload infrastructure")
Reviewed-by: Jakub Kicinski <[email protected]>

2020-08-11 17:24:54

by David Miller

[permalink] [raw]
Subject: Re: [PATCH] net/tls: Fix kmap usage

From: [email protected]
Date: Mon, 10 Aug 2020 17:02:58 -0700

> From: Ira Weiny <[email protected]>
>
> 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.
>
> Signed-off-by: Ira Weiny <[email protected]>

Applied and queued up for -stable, thank you.