[PATCH] net/tls: Fix return values for setsockopt

[PATCH] net/tls: Fix return values for setsockopt

[Valentin Vidic]

ENOTSUPP is not available in userspace:

  setsockopt failed, 524, Unknown error 524

Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>
---
 net/tls/tls_main.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
index bdca31ffe6da..5830b8e02a36 100644
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -496,7 +496,7 @@ static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
 	/* check version */
 	if (crypto_info->version != TLS_1_2_VERSION &&
 	    crypto_info->version != TLS_1_3_VERSION) {
-		rc = -ENOTSUPP;
+		rc = -EINVAL;
 		goto err_crypto_info;
 	}
 
@@ -723,7 +723,7 @@ static int tls_init(struct sock *sk)
 	 * share the ulp context.
 	 */
 	if (sk->sk_state != TCP_ESTABLISHED)
-		return -ENOTSUPP;
+		return -ENOTCONN;
 
 	/* allocate tls context */
 	write_lock_bh(&sk->sk_callback_lock);
-- 
2.20.1

Re: [PATCH] net/tls: Fix return values for setsockopt

[Jakub Kicinski]

On Tue,  3 Dec 2019 23:44:58 +0100, Valentin Vidic wrote:
> ENOTSUPP is not available in userspace:
> 
>   setsockopt failed, 524, Unknown error 524
> 
> Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>

I'm not 100% clear on whether we can change the return codes after they
had been exposed to user space for numerous releases..

But if we can - please fix the tools/testing/selftests/net/tls.c test
as well, because it expects ENOTSUPP.

> diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
> index bdca31ffe6da..5830b8e02a36 100644
> --- a/net/tls/tls_main.c
> +++ b/net/tls/tls_main.c
> @@ -496,7 +496,7 @@ static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
>  	/* check version */
>  	if (crypto_info->version != TLS_1_2_VERSION &&
>  	    crypto_info->version != TLS_1_3_VERSION) {
> -		rc = -ENOTSUPP;
> +		rc = -EINVAL;
>  		goto err_crypto_info;
>  	}
>  
> @@ -723,7 +723,7 @@ static int tls_init(struct sock *sk)
>  	 * share the ulp context.
>  	 */
>  	if (sk->sk_state != TCP_ESTABLISHED)
> -		return -ENOTSUPP;
> +		return -ENOTCONN;
>  
>  	/* allocate tls context */
>  	write_lock_bh(&sk->sk_callback_lock);

[PATCH v2] net/tls: Fix return values for setsockopt

[Valentin Vidic]

ENOTSUPP is not available in userspace:

  setsockopt failed, 524, Unknown error 524

Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>
---
v2: update error code in selftest

 net/tls/tls_main.c                | 4 ++--
 tools/testing/selftests/net/tls.c | 8 ++------
 2 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
index bdca31ffe6da..5830b8e02a36 100644
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -496,7 +496,7 @@ static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
 	/* check version */
 	if (crypto_info->version != TLS_1_2_VERSION &&
 	    crypto_info->version != TLS_1_3_VERSION) {
-		rc = -ENOTSUPP;
+		rc = -EINVAL;
 		goto err_crypto_info;
 	}
 
@@ -723,7 +723,7 @@ static int tls_init(struct sock *sk)
 	 * share the ulp context.
 	 */
 	if (sk->sk_state != TCP_ESTABLISHED)
-		return -ENOTSUPP;
+		return -ENOTCONN;
 
 	/* allocate tls context */
 	write_lock_bh(&sk->sk_callback_lock);
diff --git a/tools/testing/selftests/net/tls.c b/tools/testing/selftests/net/tls.c
index 1c8f194d6556..97c056ab43d9 100644
--- a/tools/testing/selftests/net/tls.c
+++ b/tools/testing/selftests/net/tls.c
@@ -25,10 +25,6 @@
 #define TLS_PAYLOAD_MAX_LEN 16384
 #define SOL_TLS 282
 
-#ifndef ENOTSUPP
-#define ENOTSUPP 524
-#endif
-
 FIXTURE(tls_basic)
 {
 	int fd, cfd;
@@ -1145,11 +1141,11 @@ TEST(non_established) {
 	/* TLS ULP not supported */
 	if (errno == ENOENT)
 		return;
-	EXPECT_EQ(errno, ENOTSUPP);
+	EXPECT_EQ(errno, ENOTCONN);
 
 	ret = setsockopt(sfd, IPPROTO_TCP, TCP_ULP, "tls", sizeof("tls"));
 	EXPECT_EQ(ret, -1);
-	EXPECT_EQ(errno, ENOTSUPP);
+	EXPECT_EQ(errno, ENOTCONN);
 
 	ret = getsockname(sfd, &addr, &len);
 	ASSERT_EQ(ret, 0);
-- 
2.20.1

Re: [PATCH] net/tls: Fix return values for setsockopt

[Willem de Bruijn]

On Tue, Dec 3, 2019 at 6:08 PM Jakub Kicinski
<jakub.kicinski@netronome.com> wrote:
>
> On Tue,  3 Dec 2019 23:44:58 +0100, Valentin Vidic wrote:
> > ENOTSUPP is not available in userspace:
> >
> >   setsockopt failed, 524, Unknown error 524
> >
> > Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>
>
> I'm not 100% clear on whether we can change the return codes after they
> had been exposed to user space for numerous releases..

This has also come up in the context of SO_ZEROCOPY in the past. In my
opinion the answer is no. A quick grep | wc -l in net/ shows 99
matches for this error code. Only a fraction of those probably make it
to userspace, but definitely more than this single case.

If anything, it may be time to define it in uapi?

>
>
> But if we can - please fix the tools/testing/selftests/net/tls.c test
> as well, because it expects ENOTSUPP.

Even if changing the error code, EOPNOTSUPP is arguably a better
replacement. The request itself is valid. Also considering forward
compatibility.

Re: [PATCH] net/tls: Fix return values for setsockopt

[Jakub Kicinski]

(there is a v2, in case you missed)

On Wed, 4 Dec 2019 14:22:55 -0500, Willem de Bruijn wrote:
> On Tue, Dec 3, 2019 at 6:08 PM Jakub Kicinski wrote:
> > On Tue,  3 Dec 2019 23:44:58 +0100, Valentin Vidic wrote:  
> > > ENOTSUPP is not available in userspace:
> > >
> > >   setsockopt failed, 524, Unknown error 524
> > >
> > > Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>  
> >
> > I'm not 100% clear on whether we can change the return codes after they
> > had been exposed to user space for numerous releases..  
> 
> This has also come up in the context of SO_ZEROCOPY in the past. In my
> opinion the answer is no. A quick grep | wc -l in net/ shows 99
> matches for this error code. Only a fraction of those probably make it
> to userspace, but definitely more than this single case.
> 
> If anything, it may be time to define it in uapi?

No opinion but FWIW I'm toying with some CI for netdev, I've added a
check for use of ENOTSUPP, apparently checkpatch already sniffs out
uses of ENOSYS, so seems appropriate to add this one.

> > But if we can - please fix the tools/testing/selftests/net/tls.c test
> > as well, because it expects ENOTSUPP.  
> 
> Even if changing the error code, EOPNOTSUPP is arguably a better
> replacement. The request itself is valid. Also considering forward
> compatibility.

For the case TLS version case?

Re: [PATCH] net/tls: Fix return values for setsockopt

[Willem de Bruijn]

On Wed, Dec 4, 2019 at 2:36 PM Jakub Kicinski
<jakub.kicinski@netronome.com> wrote:
>
> (there is a v2, in case you missed)

Thanks. I meant to respond to your comment. (but should have done sooner :)

> On Wed, 4 Dec 2019 14:22:55 -0500, Willem de Bruijn wrote:
> > On Tue, Dec 3, 2019 at 6:08 PM Jakub Kicinski wrote:
> > > On Tue,  3 Dec 2019 23:44:58 +0100, Valentin Vidic wrote:
> > > > ENOTSUPP is not available in userspace:
> > > >
> > > >   setsockopt failed, 524, Unknown error 524
> > > >
> > > > Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>
> > >
> > > I'm not 100% clear on whether we can change the return codes after they
> > > had been exposed to user space for numerous releases..
> >
> > This has also come up in the context of SO_ZEROCOPY in the past. In my
> > opinion the answer is no. A quick grep | wc -l in net/ shows 99
> > matches for this error code. Only a fraction of those probably make it
> > to userspace, but definitely more than this single case.
> >
> > If anything, it may be time to define it in uapi?
>
> No opinion but FWIW I'm toying with some CI for netdev, I've added a
> check for use of ENOTSUPP, apparently checkpatch already sniffs out
> uses of ENOSYS, so seems appropriate to add this one.

Good idea if not exposing this in UAPI.

> > > But if we can - please fix the tools/testing/selftests/net/tls.c test
> > > as well, because it expects ENOTSUPP.
> >
> > Even if changing the error code, EOPNOTSUPP is arguably a better
> > replacement. The request itself is valid. Also considering forward
> > compatibility.
>
> For the case TLS version case?

Yes. It's a more specific signal. Quite a few error paths already return EINVAL.

Re: [PATCH] net/tls: Fix return values for setsockopt

[David Miller]

From: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Date: Wed, 4 Dec 2019 15:43:00 -0500

> On Wed, Dec 4, 2019 at 2:36 PM Jakub Kicinski
> <jakub.kicinski@netronome.com> wrote:
>>
>> (there is a v2, in case you missed)
> 
> Thanks. I meant to respond to your comment. (but should have done sooner :)
> 
>> On Wed, 4 Dec 2019 14:22:55 -0500, Willem de Bruijn wrote:
>> > On Tue, Dec 3, 2019 at 6:08 PM Jakub Kicinski wrote:
>> > > On Tue,  3 Dec 2019 23:44:58 +0100, Valentin Vidic wrote:
>> > > > ENOTSUPP is not available in userspace:
>> > > >
>> > > >   setsockopt failed, 524, Unknown error 524
>> > > >
>> > > > Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>
>> > >
>> > > I'm not 100% clear on whether we can change the return codes after they
>> > > had been exposed to user space for numerous releases..
>> >
>> > This has also come up in the context of SO_ZEROCOPY in the past. In my
>> > opinion the answer is no. A quick grep | wc -l in net/ shows 99
>> > matches for this error code. Only a fraction of those probably make it
>> > to userspace, but definitely more than this single case.
>> >
>> > If anything, it may be time to define it in uapi?
>>
>> No opinion but FWIW I'm toying with some CI for netdev, I've added a
>> check for use of ENOTSUPP, apparently checkpatch already sniffs out
>> uses of ENOSYS, so seems appropriate to add this one.
> 
> Good idea if not exposing this in UAPI.

I'm trying to understand this part of the discussion.

If we have been returning a non-valid error code, this 524 internal
kernel thing, it is _NOT_ an exposed UAPI.

It is a kernel bug and we should fix it.

If userspace anywhere is checking for 524, that is what needs to be fixed.

Do we agree on this point?

Re: [PATCH] net/tls: Fix return values for setsockopt

[Jakub Kicinski]

On Wed, 04 Dec 2019 12:51:35 -0800 (PST), David Miller wrote:
> From: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
> Date: Wed, 4 Dec 2019 15:43:00 -0500
> > On Wed, Dec 4, 2019 at 2:36 PM Jakub Kicinski wrote:  
> >> On Wed, 4 Dec 2019 14:22:55 -0500, Willem de Bruijn wrote:  
> >> > On Tue, Dec 3, 2019 at 6:08 PM Jakub Kicinski wrote:  
> >> > > On Tue,  3 Dec 2019 23:44:58 +0100, Valentin Vidic wrote:  
> >> > > > ENOTSUPP is not available in userspace:
> >> > > >
> >> > > >   setsockopt failed, 524, Unknown error 524
> >> > > >
> >> > > > Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>  
> >> > >
> >> > > I'm not 100% clear on whether we can change the return codes after they
> >> > > had been exposed to user space for numerous releases..  
> >> >
> >> > This has also come up in the context of SO_ZEROCOPY in the past. In my
> >> > opinion the answer is no. A quick grep | wc -l in net/ shows 99
> >> > matches for this error code. Only a fraction of those probably make it
> >> > to userspace, but definitely more than this single case.
> >> >
> >> > If anything, it may be time to define it in uapi?  
> >>
> >> No opinion but FWIW I'm toying with some CI for netdev, I've added a
> >> check for use of ENOTSUPP, apparently checkpatch already sniffs out
> >> uses of ENOSYS, so seems appropriate to add this one.  
> > 
> > Good idea if not exposing this in UAPI.  
> 
> I'm trying to understand this part of the discussion.
> 
> If we have been returning a non-valid error code, this 524 internal
> kernel thing, it is _NOT_ an exposed UAPI.
> 
> It is a kernel bug and we should fix it.

I agree. We should just fix this.

As Willem points out the use of this error code has spread, but in
theory I'm a co-maintainer of the TLS code now, and my maintainer 
gut says "just fix it" :)

> If userspace anywhere is checking for 524, that is what needs to be fixed.

FWIW I did a quick grep through openssl and gnutls and fbthrift and I
see no references to ENOTSUPP or 524.

Valentin, what's the strategy you're using for this fix? There's a
bunch of ENOTSUPP in net/tls/tls_sw.c as well, could you convert those,
too?

Re: [PATCH] net/tls: Fix return values for setsockopt

[David Miller]

From: Jakub Kicinski <jakub.kicinski@netronome.com>
Date: Wed, 4 Dec 2019 15:01:36 -0800

> Valentin, what's the strategy you're using for this fix? There's a
> bunch of ENOTSUPP in net/tls/tls_sw.c as well, could you convert those,
> too?

Yes I see those as well, let's get them all in one patch ok?

[PATCH v3] net/tls: Fix return values to avoid ENOTSUPP

[Valentin Vidic]

ENOTSUPP is not available in userspace, for example:

  setsockopt failed, 524, Unknown error 524

Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>
---
v3: replace ENOTSUPP in other functions
v2: update error code in selftest

 net/tls/tls_device.c              | 8 ++++----
 net/tls/tls_main.c                | 4 ++--
 net/tls/tls_sw.c                  | 8 ++++----
 tools/testing/selftests/net/tls.c | 8 ++------
 4 files changed, 12 insertions(+), 16 deletions(-)

diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index 0683788bbef0..cd91ad812291 100644
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -429,7 +429,7 @@ static int tls_push_data(struct sock *sk,
 
 	if (flags &
 	    ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST))
-		return -ENOTSUPP;
+		return -EOPNOTSUPP;
 
 	if (unlikely(sk->sk_err))
 		return -sk->sk_err;
@@ -571,7 +571,7 @@ int tls_device_sendpage(struct sock *sk, struct page *page,
 	lock_sock(sk);
 
 	if (flags & MSG_OOB) {
-		rc = -ENOTSUPP;
+		rc = -EOPNOTSUPP;
 		goto out;
 	}
 
@@ -1023,7 +1023,7 @@ int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
 	}
 
 	if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
-		rc = -ENOTSUPP;
+		rc = -EOPNOTSUPP;
 		goto release_netdev;
 	}
 
@@ -1098,7 +1098,7 @@ int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
 	}
 
 	if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
-		rc = -ENOTSUPP;
+		rc = -EOPNOTSUPP;
 		goto release_netdev;
 	}
 
diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
index bdca31ffe6da..5830b8e02a36 100644
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -496,7 +496,7 @@ static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
 	/* check version */
 	if (crypto_info->version != TLS_1_2_VERSION &&
 	    crypto_info->version != TLS_1_3_VERSION) {
-		rc = -ENOTSUPP;
+		rc = -EINVAL;
 		goto err_crypto_info;
 	}
 
@@ -723,7 +723,7 @@ static int tls_init(struct sock *sk)
 	 * share the ulp context.
 	 */
 	if (sk->sk_state != TCP_ESTABLISHED)
-		return -ENOTSUPP;
+		return -ENOTCONN;
 
 	/* allocate tls context */
 	write_lock_bh(&sk->sk_callback_lock);
diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index da9f9ce51e7b..2969dc30e4e0 100644
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -900,7 +900,7 @@ int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 	int ret = 0;
 
 	if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL))
-		return -ENOTSUPP;
+		return -EOPNOTSUPP;
 
 	mutex_lock(&tls_ctx->tx_lock);
 	lock_sock(sk);
@@ -1215,7 +1215,7 @@ int tls_sw_sendpage_locked(struct sock *sk, struct page *page,
 	if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
 		      MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY |
 		      MSG_NO_SHARED_FRAGS))
-		return -ENOTSUPP;
+		return -EOPNOTSUPP;
 
 	return tls_sw_do_sendpage(sk, page, offset, size, flags);
 }
@@ -1228,7 +1228,7 @@ int tls_sw_sendpage(struct sock *sk, struct page *page,
 
 	if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
 		      MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY))
-		return -ENOTSUPP;
+		return -EOPNOTSUPP;
 
 	mutex_lock(&tls_ctx->tx_lock);
 	lock_sock(sk);
@@ -1927,7 +1927,7 @@ ssize_t tls_sw_splice_read(struct socket *sock,  loff_t *ppos,
 
 		/* splice does not support reading control messages */
 		if (ctx->control != TLS_RECORD_TYPE_DATA) {
-			err = -ENOTSUPP;
+			err = -EINVAL;
 			goto splice_read_end;
 		}
 
diff --git a/tools/testing/selftests/net/tls.c b/tools/testing/selftests/net/tls.c
index 1c8f194d6556..97c056ab43d9 100644
--- a/tools/testing/selftests/net/tls.c
+++ b/tools/testing/selftests/net/tls.c
@@ -25,10 +25,6 @@
 #define TLS_PAYLOAD_MAX_LEN 16384
 #define SOL_TLS 282
 
-#ifndef ENOTSUPP
-#define ENOTSUPP 524
-#endif
-
 FIXTURE(tls_basic)
 {
 	int fd, cfd;
@@ -1145,11 +1141,11 @@ TEST(non_established) {
 	/* TLS ULP not supported */
 	if (errno == ENOENT)
 		return;
-	EXPECT_EQ(errno, ENOTSUPP);
+	EXPECT_EQ(errno, ENOTCONN);
 
 	ret = setsockopt(sfd, IPPROTO_TCP, TCP_ULP, "tls", sizeof("tls"));
 	EXPECT_EQ(ret, -1);
-	EXPECT_EQ(errno, ENOTSUPP);
+	EXPECT_EQ(errno, ENOTCONN);
 
 	ret = getsockname(sfd, &addr, &len);
 	ASSERT_EQ(ret, 0);
-- 
2.20.1

Re: [PATCH v3] net/tls: Fix return values to avoid ENOTSUPP

[Jakub Kicinski]

On Thu,  5 Dec 2019 07:41:18 +0100, Valentin Vidic wrote:
> ENOTSUPP is not available in userspace, for example:
> 
>   setsockopt failed, 524, Unknown error 524
> 
> Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>

> diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
> index 0683788bbef0..cd91ad812291 100644
> --- a/net/tls/tls_device.c
> +++ b/net/tls/tls_device.c
> @@ -429,7 +429,7 @@ static int tls_push_data(struct sock *sk,
>  
>  	if (flags &
>  	    ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST))
> -		return -ENOTSUPP;
> +		return -EOPNOTSUPP;
>  
>  	if (unlikely(sk->sk_err))
>  		return -sk->sk_err;
> @@ -571,7 +571,7 @@ int tls_device_sendpage(struct sock *sk, struct page *page,
>  	lock_sock(sk);
>  
>  	if (flags & MSG_OOB) {
> -		rc = -ENOTSUPP;
> +		rc = -EOPNOTSUPP;

Perhaps the flag checks should return EINVAL? Willem any opinions?

>  		goto out;
>  	}
>  
> @@ -1023,7 +1023,7 @@ int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
>  	}
>  
>  	if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
> -		rc = -ENOTSUPP;
> +		rc = -EOPNOTSUPP;
>  		goto release_netdev;
>  	}
>  
> @@ -1098,7 +1098,7 @@ int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
>  	}
>  
>  	if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
> -		rc = -ENOTSUPP;
> +		rc = -EOPNOTSUPP;
>  		goto release_netdev;
>  	}
>  
> diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
> index bdca31ffe6da..5830b8e02a36 100644
> --- a/net/tls/tls_main.c
> +++ b/net/tls/tls_main.c
> @@ -496,7 +496,7 @@ static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
>  	/* check version */
>  	if (crypto_info->version != TLS_1_2_VERSION &&
>  	    crypto_info->version != TLS_1_3_VERSION) {
> -		rc = -ENOTSUPP;
> +		rc = -EINVAL;

This one I think Willem asked to be EOPNOTSUPP OTOH.

>  		goto err_crypto_info;
>  	}
>  
> @@ -723,7 +723,7 @@ static int tls_init(struct sock *sk)
>  	 * share the ulp context.
>  	 */
>  	if (sk->sk_state != TCP_ESTABLISHED)
> -		return -ENOTSUPP;
> +		return -ENOTCONN;
>  
>  	/* allocate tls context */
>  	write_lock_bh(&sk->sk_callback_lock);
> diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
> index da9f9ce51e7b..2969dc30e4e0 100644
> --- a/net/tls/tls_sw.c
> +++ b/net/tls/tls_sw.c
> @@ -900,7 +900,7 @@ int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
>  	int ret = 0;
>  
>  	if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL))
> -		return -ENOTSUPP;
> +		return -EOPNOTSUPP;
>  
>  	mutex_lock(&tls_ctx->tx_lock);
>  	lock_sock(sk);
> @@ -1215,7 +1215,7 @@ int tls_sw_sendpage_locked(struct sock *sk, struct page *page,
>  	if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
>  		      MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY |
>  		      MSG_NO_SHARED_FRAGS))
> -		return -ENOTSUPP;
> +		return -EOPNOTSUPP;
>  
>  	return tls_sw_do_sendpage(sk, page, offset, size, flags);
>  }
> @@ -1228,7 +1228,7 @@ int tls_sw_sendpage(struct sock *sk, struct page *page,
>  
>  	if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
>  		      MSG_SENDPAGE_NOTLAST | MSG_SENDPAGE_NOPOLICY))
> -		return -ENOTSUPP;
> +		return -EOPNOTSUPP;

Same suggestion for flags checks in tls_sw.c

>  
>  	mutex_lock(&tls_ctx->tx_lock);
>  	lock_sock(sk);
> @@ -1927,7 +1927,7 @@ ssize_t tls_sw_splice_read(struct socket *sock,  loff_t *ppos,
>  
>  		/* splice does not support reading control messages */
>  		if (ctx->control != TLS_RECORD_TYPE_DATA) {
> -			err = -ENOTSUPP;
> +			err = -EINVAL;
>  			goto splice_read_end;
>  		}
>  

Re: [PATCH v3] net/tls: Fix return values to avoid ENOTSUPP

[Willem de Bruijn]

On Thu, Dec 5, 2019 at 2:34 PM Jakub Kicinski
<jakub.kicinski@netronome.com> wrote:
>
> On Thu,  5 Dec 2019 07:41:18 +0100, Valentin Vidic wrote:
> > ENOTSUPP is not available in userspace, for example:
> >
> >   setsockopt failed, 524, Unknown error 524
> >
> > Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>
>
> > diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
> > index 0683788bbef0..cd91ad812291 100644
> > --- a/net/tls/tls_device.c
> > +++ b/net/tls/tls_device.c
> > @@ -429,7 +429,7 @@ static int tls_push_data(struct sock *sk,
> >
> >       if (flags &
> >           ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST))
> > -             return -ENOTSUPP;
> > +             return -EOPNOTSUPP;
> >
> >       if (unlikely(sk->sk_err))
> >               return -sk->sk_err;
> > @@ -571,7 +571,7 @@ int tls_device_sendpage(struct sock *sk, struct page *page,
> >       lock_sock(sk);
> >
> >       if (flags & MSG_OOB) {
> > -             rc = -ENOTSUPP;
> > +             rc = -EOPNOTSUPP;
>
> Perhaps the flag checks should return EINVAL? Willem any opinions?

No strong opinion. Judging from do_tcp_sendpages MSG_OOB is a
supported flag in general for sendpage, so signaling that the TLS
variant cannot support that otherwise valid request sounds fine to me.

>
> >               goto out;
> >       }
> >
> > @@ -1023,7 +1023,7 @@ int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
> >       }
> >
> >       if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
> > -             rc = -ENOTSUPP;
> > +             rc = -EOPNOTSUPP;
> >               goto release_netdev;
> >       }
> >
> > @@ -1098,7 +1098,7 @@ int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
> >       }
> >
> >       if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
> > -             rc = -ENOTSUPP;
> > +             rc = -EOPNOTSUPP;
> >               goto release_netdev;
> >       }
> >
> > diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
> > index bdca31ffe6da..5830b8e02a36 100644
> > --- a/net/tls/tls_main.c
> > +++ b/net/tls/tls_main.c
> > @@ -496,7 +496,7 @@ static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
> >       /* check version */
> >       if (crypto_info->version != TLS_1_2_VERSION &&
> >           crypto_info->version != TLS_1_3_VERSION) {
> > -             rc = -ENOTSUPP;
> > +             rc = -EINVAL;
>
> This one I think Willem asked to be EOPNOTSUPP OTOH.

Indeed (assuming no one disagrees). Based on the same rationale: the
request may be valid, it just cannot be accommodated (yet).

Re: [PATCH v3] net/tls: Fix return values to avoid ENOTSUPP

[Valentin Vidić]

On Thu, Dec 05, 2019 at 03:06:55PM -0500, Willem de Bruijn wrote:
> On Thu, Dec 5, 2019 at 2:34 PM Jakub Kicinski
> <jakub.kicinski@netronome.com> wrote:
> >
> > On Thu,  5 Dec 2019 07:41:18 +0100, Valentin Vidic wrote:
> > > ENOTSUPP is not available in userspace, for example:
> > >
> > >   setsockopt failed, 524, Unknown error 524
> > >
> > > Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>
> >
> > > diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
> > > index 0683788bbef0..cd91ad812291 100644
> > > --- a/net/tls/tls_device.c
> > > +++ b/net/tls/tls_device.c
> > > @@ -429,7 +429,7 @@ static int tls_push_data(struct sock *sk,
> > >
> > >       if (flags &
> > >           ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST))
> > > -             return -ENOTSUPP;
> > > +             return -EOPNOTSUPP;
> > >
> > >       if (unlikely(sk->sk_err))
> > >               return -sk->sk_err;
> > > @@ -571,7 +571,7 @@ int tls_device_sendpage(struct sock *sk, struct page *page,
> > >       lock_sock(sk);
> > >
> > >       if (flags & MSG_OOB) {
> > > -             rc = -ENOTSUPP;
> > > +             rc = -EOPNOTSUPP;
> >
> > Perhaps the flag checks should return EINVAL? Willem any opinions?
> 
> No strong opinion. Judging from do_tcp_sendpages MSG_OOB is a
> supported flag in general for sendpage, so signaling that the TLS
> variant cannot support that otherwise valid request sounds fine to me.

I based these on the description from the sendmsg manpage, but you decide:

EOPNOTSUPP
    Some bit in the flags argument is inappropriate for the socket type.

> > > diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
> > > index bdca31ffe6da..5830b8e02a36 100644
> > > --- a/net/tls/tls_main.c
> > > +++ b/net/tls/tls_main.c
> > > @@ -496,7 +496,7 @@ static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
> > >       /* check version */
> > >       if (crypto_info->version != TLS_1_2_VERSION &&
> > >           crypto_info->version != TLS_1_3_VERSION) {
> > > -             rc = -ENOTSUPP;
> > > +             rc = -EINVAL;
> >
> > This one I think Willem asked to be EOPNOTSUPP OTOH.
> 
> Indeed (assuming no one disagrees). Based on the same rationale: the
> request may be valid, it just cannot be accommodated (yet).

In this case other checks in the same function like crypto_info->cipher_type
return EINVAL, so I used the same here.

-- 
Valentin

Re: [PATCH v3] net/tls: Fix return values to avoid ENOTSUPP

[Jakub Kicinski]

On Thu, 5 Dec 2019 21:43:43 +0100, Valentin Vidić wrote:
> > > On Thu,  5 Dec 2019 07:41:18 +0100, Valentin Vidic wrote:  
> > > > ENOTSUPP is not available in userspace, for example:
> > > >
> > > >   setsockopt failed, 524, Unknown error 524
> > > >
> > > > Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>  
> > >  
> > > > diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
> > > > index 0683788bbef0..cd91ad812291 100644
> > > > --- a/net/tls/tls_device.c
> > > > +++ b/net/tls/tls_device.c
> > > > @@ -429,7 +429,7 @@ static int tls_push_data(struct sock *sk,
> > > >
> > > >       if (flags &
> > > >           ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST))
> > > > -             return -ENOTSUPP;
> > > > +             return -EOPNOTSUPP;
> > > >
> > > >       if (unlikely(sk->sk_err))
> > > >               return -sk->sk_err;
> > > > @@ -571,7 +571,7 @@ int tls_device_sendpage(struct sock *sk, struct page *page,
> > > >       lock_sock(sk);
> > > >
> > > >       if (flags & MSG_OOB) {
> > > > -             rc = -ENOTSUPP;
> > > > +             rc = -EOPNOTSUPP;  
> > >
> > > Perhaps the flag checks should return EINVAL? Willem any opinions?  
> > 
> > No strong opinion. Judging from do_tcp_sendpages MSG_OOB is a
> > supported flag in general for sendpage, so signaling that the TLS
> > variant cannot support that otherwise valid request sounds fine to me.  
> 
> I based these on the description from the sendmsg manpage, but you decide:
> 
> EOPNOTSUPP
>     Some bit in the flags argument is inappropriate for the socket type.
> 
> > > > diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
> > > > index bdca31ffe6da..5830b8e02a36 100644
> > > > --- a/net/tls/tls_main.c
> > > > +++ b/net/tls/tls_main.c
> > > > @@ -496,7 +496,7 @@ static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
> > > >       /* check version */
> > > >       if (crypto_info->version != TLS_1_2_VERSION &&
> > > >           crypto_info->version != TLS_1_3_VERSION) {
> > > > -             rc = -ENOTSUPP;
> > > > +             rc = -EINVAL;  
> > >
> > > This one I think Willem asked to be EOPNOTSUPP OTOH.  
> > 
> > Indeed (assuming no one disagrees). Based on the same rationale: the
> > request may be valid, it just cannot be accommodated (yet).  
> 
> In this case other checks in the same function like crypto_info->cipher_type
> return EINVAL, so I used the same here.

Thanks for explaining, in that case:

Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>

Re: [PATCH v3] net/tls: Fix return values to avoid ENOTSUPP

[Willem de Bruijn]

On Thu, Dec 5, 2019 at 3:44 PM Valentin Vidić
<vvidic@valentin-vidic.from.hr> wrote:
>
> On Thu, Dec 05, 2019 at 03:06:55PM -0500, Willem de Bruijn wrote:
> > On Thu, Dec 5, 2019 at 2:34 PM Jakub Kicinski
> > <jakub.kicinski@netronome.com> wrote:
> > >
> > > On Thu,  5 Dec 2019 07:41:18 +0100, Valentin Vidic wrote:
> > > > ENOTSUPP is not available in userspace, for example:
> > > >
> > > >   setsockopt failed, 524, Unknown error 524
> > > >
> > > > Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>
> > >
> > > > diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
> > > > index 0683788bbef0..cd91ad812291 100644
> > > > --- a/net/tls/tls_device.c
> > > > +++ b/net/tls/tls_device.c
> > > > @@ -429,7 +429,7 @@ static int tls_push_data(struct sock *sk,
> > > >
> > > >       if (flags &
> > > >           ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST))
> > > > -             return -ENOTSUPP;
> > > > +             return -EOPNOTSUPP;
> > > >
> > > >       if (unlikely(sk->sk_err))
> > > >               return -sk->sk_err;
> > > > @@ -571,7 +571,7 @@ int tls_device_sendpage(struct sock *sk, struct page *page,
> > > >       lock_sock(sk);
> > > >
> > > >       if (flags & MSG_OOB) {
> > > > -             rc = -ENOTSUPP;
> > > > +             rc = -EOPNOTSUPP;
> > >
> > > Perhaps the flag checks should return EINVAL? Willem any opinions?
> >
> > No strong opinion. Judging from do_tcp_sendpages MSG_OOB is a
> > supported flag in general for sendpage, so signaling that the TLS
> > variant cannot support that otherwise valid request sounds fine to me.
>
> I based these on the description from the sendmsg manpage, but you decide:
>
> EOPNOTSUPP
>     Some bit in the flags argument is inappropriate for the socket type.

Interesting. That is a narrower interpretation than asm-generic/errno.h

  #define EOPNOTSUPP      95      /* Operation not supported on
transport endpoint */

which is also the string that strerror() generates.

>
> > > > diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
> > > > index bdca31ffe6da..5830b8e02a36 100644
> > > > --- a/net/tls/tls_main.c
> > > > +++ b/net/tls/tls_main.c
> > > > @@ -496,7 +496,7 @@ static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
> > > >       /* check version */
> > > >       if (crypto_info->version != TLS_1_2_VERSION &&
> > > >           crypto_info->version != TLS_1_3_VERSION) {
> > > > -             rc = -ENOTSUPP;
> > > > +             rc = -EINVAL;
> > >
> > > This one I think Willem asked to be EOPNOTSUPP OTOH.
> >
> > Indeed (assuming no one disagrees). Based on the same rationale: the
> > request may be valid, it just cannot be accommodated (yet).
>
> In this case other checks in the same function like crypto_info->cipher_type
> return EINVAL, so I used the same here.

That makes sense.

I think there is a fundamental difference between, say, passing an
argument of incorrect length (optlen < sizeof(..)) and asking for a
possibly unsupported cipher mode. But consistency trumps that.

I don't mean to drag this out by bike-shedding.

Happy to defer to maintainers on whether the errno on published code
can and should be changed, which is the more fundamental issue than
the exact errno.

FWIW, I also did not see existing openssl and gnutls callers test the
specific errno. The calls just fail on any setsockopt return value -1.

Re: [PATCH v3] net/tls: Fix return values to avoid ENOTSUPP

[Valentin Vidić]

On Thu, Dec 05, 2019 at 04:26:14PM -0500, Willem de Bruijn wrote:
> > I based these on the description from the sendmsg manpage, but you decide:
> >
> > EOPNOTSUPP
> >     Some bit in the flags argument is inappropriate for the socket type.
> 
> Interesting. That is a narrower interpretation than asm-generic/errno.h
> 
>   #define EOPNOTSUPP      95      /* Operation not supported on
> transport endpoint */
> 
> which is also the string that strerror() generates.

Found one interesting example where EINVAL seems to mean "this value will never work"
and EOPNOTSUPP means "this value will not work in the current state/type of socket":

        case TCP_FASTOPEN_CONNECT:
                if (val > 1 || val < 0) {
                        err = -EINVAL;
                } else if (net->ipv4.sysctl_tcp_fastopen & TFO_CLIENT_ENABLE) {
                        if (sk->sk_state == TCP_CLOSE)
                                tp->fastopen_connect = val;
                        else
                                err = -EINVAL;
                } else {
                        err = -EOPNOTSUPP;
                }
                break;

> I think there is a fundamental difference between, say, passing an
> argument of incorrect length (optlen < sizeof(..)) and asking for a
> possibly unsupported cipher mode. But consistency trumps that.
> 
> I don't mean to drag this out by bike-shedding.
> 
> Happy to defer to maintainers on whether the errno on published code
> can and should be changed, which is the more fundamental issue than
> the exact errno.
> 
> FWIW, I also did not see existing openssl and gnutls callers test the
> specific errno. The calls just fail on any setsockopt return value -1.

Right, I'm also fine with whatever the maintainer decides to take :)

-- 
Valentin

Re: [PATCH v3] net/tls: Fix return values to avoid ENOTSUPP

[David Miller]

From: Valentin Vidic <vvidic@valentin-vidic.from.hr>
Date: Thu,  5 Dec 2019 07:41:18 +0100

> ENOTSUPP is not available in userspace, for example:
> 
>   setsockopt failed, 524, Unknown error 524
> 
> Signed-off-by: Valentin Vidic <vvidic@valentin-vidic.from.hr>

Applied and queued up for -stable, thanks.