Hmmm, that's really strange, i don't see CV in mailing lists. Here it is anyway:
Subject: [PATCH net v4 0/4] several updates to virtio/vsock
Hello,
this patchset evolved from previous v2 version (see link below). It does
several updates to virtio/vsock:
1) Changes 'virtio_transport_inc/dec_rx_pkt()' interface. Now instead of
using skbuff state ('head' and 'data' pointers) to update 'fwd_cnt'
and 'rx_bytes', integer value is passed as an input argument. This
makes code more simple, because in this case we don't need to update
skbuff state before calling 'virtio_transport_inc/dec_rx_pkt()'. In
more common words - we don't need to change skbuff state to update
'rx_bytes' and 'fwd_cnt' correctly.
2) For SOCK_STREAM, when copying data to user fails, current skbuff is
not dropped. Next read attempt will use same skbuff and last offset.
Instead of 'skb_dequeue()', 'skb_peek()' + '__skb_unlink()' are used.
This behaviour was implemented before skbuff support.
3) For SOCK_SEQPACKET it removes unneeded 'skb_pull()' call, because for
this type of socket each skbuff is used only once: after removing it
from socket's queue, it will be freed anyway.
Test for 2) also added:
Test tries to 'recv()' data to NULL buffer, then does 'recv()' with valid
buffer. For SOCK_STREAM second 'recv()' must return data, because skbuff
must not be dropped, but for SOCK_SEQPACKET skbuff will be dropped by
kernel, and 'recv()' will return EAGAIN.
Link to v1 on lore:
https://lore.kernel.org/netdev/c2d3e204-89d9-88e9-8a15-3fe027e56b4b@xxxxxxxxxxxxxx/
Link to v2 on lore:
https://lore.kernel.org/netdev/a7ab414b-5e41-c7b6-250b-e8401f335859@xxxxxxxxxxxxxx/
Link to v3 on lore:
https://lore.kernel.org/netdev/0abeec42-a11d-3a51-453b-6acf76604f2e@xxxxxxxxxxxxxx/
Change log:
v1 -> v2:
- For SOCK_SEQPACKET call 'skb_pull()' also in case of copy failure or
dropping skbuff (when we just waiting message end).
- Handle copy failure for SOCK_STREAM in the same manner (plus free
current skbuff).
- Replace bug repdroducer with new test in vsock_test.c
v2 -> v3:
- Replace patch which removes 'skb->len' subtraction from function
'virtio_transport_dec_rx_pkt()' with patch which updates functions
'virtio_transport_inc/dec_rx_pkt()' by passing integer argument
instead of skbuff pointer.
- Replace patch which drops skbuff when copying to user fails with
patch which changes this behaviour by keeping skbuff in queue until
it has no data.
- Add patch for SOCK_SEQPACKET which removes redundant 'skb_pull()'
call on read.
- I remove "Fixes" tag from all patches, because all of them now change
code logic, not only fix something.
v3 -> v4:
- Update commit messages in all patches except test.
- Add "Fixes" tag to all patches except test.
Arseniy Krasnov (4):
virtio/vsock: don't use skbuff state to account credit
virtio/vsock: remove redundant 'skb_pull()' call
virtio/vsock: don't drop skbuff on copy failure
test/vsock: copy to user failure test
net/vmw_vsock/virtio_transport_common.c | 29 +++---
tools/testing/vsock/vsock_test.c | 118 ++++++++++++++++++++++++
2 files changed, 131 insertions(+), 16 deletions(-)
--
2.25.1
On 14.03.2023 13:47, Arseniy Krasnov wrote:
> This adds SOCK_STREAM and SOCK_SEQPACKET tests for invalid buffer case.
> It tries to read data to NULL buffer (data already presents in socket's
> queue), then uses valid buffer. For SOCK_STREAM second read must return
> data, because skbuff is not dropped, but for SOCK_SEQPACKET skbuff will
> be dropped by kernel, and 'recv()' will return EAGAIN.
>
> Signed-off-by: Arseniy Krasnov <AVKrasnov@xxxxxxxxxxxxxx>
> Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
> ---
> tools/testing/vsock/vsock_test.c | 118 +++++++++++++++++++++++++++++++
> 1 file changed, 118 insertions(+)
>
> diff --git a/tools/testing/vsock/vsock_test.c b/tools/testing/vsock/vsock_test.c
> index 67e9f9df3a8c..3de10dbb50f5 100644
> --- a/tools/testing/vsock/vsock_test.c
> +++ b/tools/testing/vsock/vsock_test.c
> @@ -860,6 +860,114 @@ static void test_stream_poll_rcvlowat_client(const struct test_opts *opts)
> close(fd);
> }
>
> +#define INV_BUF_TEST_DATA_LEN 512
> +
> +static void test_inv_buf_client(const struct test_opts *opts, bool stream)
> +{
> + unsigned char data[INV_BUF_TEST_DATA_LEN] = {0};
> + ssize_t ret;
> + int fd;
> +
> + if (stream)
> + fd = vsock_stream_connect(opts->peer_cid, 1234);
> + else
> + fd = vsock_seqpacket_connect(opts->peer_cid, 1234);
> +
> + if (fd < 0) {
> + perror("connect");
> + exit(EXIT_FAILURE);
> + }
> +
> + control_expectln("SENDDONE");
> +
> + /* Use invalid buffer here. */
> + ret = recv(fd, NULL, sizeof(data), 0);
> + if (ret != -1) {
> + fprintf(stderr, "expected recv(2) failure, got %zi\n", ret);
> + exit(EXIT_FAILURE);
> + }
> +
> + if (errno != ENOMEM) {
> + fprintf(stderr, "unexpected recv(2) errno %d\n", errno);
> + exit(EXIT_FAILURE);
> + }
> +
> + ret = recv(fd, data, sizeof(data), MSG_DONTWAIT);
> +
> + if (stream) {
> + /* For SOCK_STREAM we must continue reading. */
> + if (ret != sizeof(data)) {
> + fprintf(stderr, "expected recv(2) success, got %zi\n", ret);
> + exit(EXIT_FAILURE);
> + }
> + /* Don't check errno in case of success. */
> + } else {
> + /* For SOCK_SEQPACKET socket's queue must be empty. */
> + if (ret != -1) {
> + fprintf(stderr, "expected recv(2) failure, got %zi\n", ret);
> + exit(EXIT_FAILURE);
> + }
> +
> + if (errno != EAGAIN) {
> + fprintf(stderr, "unexpected recv(2) errno %d\n", errno);
> + exit(EXIT_FAILURE);
> + }
> + }
> +
> + control_writeln("DONE");
> +
> + close(fd);
> +}
> +
> +static void test_inv_buf_server(const struct test_opts *opts, bool stream)
> +{
> + unsigned char data[INV_BUF_TEST_DATA_LEN] = {0};
> + ssize_t res;
> + int fd;
> +
> + if (stream)
> + fd = vsock_stream_accept(VMADDR_CID_ANY, 1234, NULL);
> + else
> + fd = vsock_seqpacket_accept(VMADDR_CID_ANY, 1234, NULL);
> +
> + if (fd < 0) {
> + perror("accept");
> + exit(EXIT_FAILURE);
> + }
> +
> + res = send(fd, data, sizeof(data), 0);
> + if (res != sizeof(data)) {
> + fprintf(stderr, "unexpected send(2) result %zi\n", res);
> + exit(EXIT_FAILURE);
> + }
> +
> + control_writeln("SENDDONE");
> +
> + control_expectln("DONE");
> +
> + close(fd);
> +}
> +
> +static void test_stream_inv_buf_client(const struct test_opts *opts)
> +{
> + test_inv_buf_client(opts, true);
> +}
> +
> +static void test_stream_inv_buf_server(const struct test_opts *opts)
> +{
> + test_inv_buf_server(opts, true);
> +}
> +
> +static void test_seqpacket_inv_buf_client(const struct test_opts *opts)
> +{
> + test_inv_buf_client(opts, false);
> +}
> +
> +static void test_seqpacket_inv_buf_server(const struct test_opts *opts)
> +{
> + test_inv_buf_server(opts, false);
> +}
> +
> static struct test_case test_cases[] = {
> {
> .name = "SOCK_STREAM connection reset",
> @@ -920,6 +1028,16 @@ static struct test_case test_cases[] = {
> .run_client = test_seqpacket_bigmsg_client,
> .run_server = test_seqpacket_bigmsg_server,
> },
> + {
> + .name = "SOCK_STREAM test invalid buffer",
> + .run_client = test_stream_inv_buf_client,
> + .run_server = test_stream_inv_buf_server,
> + },
> + {
> + .name = "SOCK_SEQPACKET test invalid buffer",
> + .run_client = test_seqpacket_inv_buf_client,
> + .run_server = test_seqpacket_inv_buf_server,
> + },
> {},
> };
>
