From: Jon Maloy jmaloy@redhat.com

When doing further testing of the recently added SO_PEEK_OFF feature for TCP I realized I had omitted to add it for TCP/IPv6.

I do that here.

Fixes: 05ea491641d3 ("tcp: add support for SO_PEEK_OFF socket option") Reviewed-by: Eric Dumazet edumazet@google.com Reviewed-by: David Gibson david@gibson.dropbear.id.au Reviewed-by: Stefano Brivio sbrivio@redhat.com Tested-by: Stefano Brivio sbrivio@redhat.com Signed-off-by: Jon Maloy jmaloy@redhat.com

--- v2: Removed redundant whitespace between "Fixes" and "Signed-off-by" lines. Based on feedback from J. Kicinski. v3: Rephrased commit log to make it clear how the TCP/IPv6 omission was discovered. Based on feedback from J. Kicinski. --- net/ipv6/af_inet6.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index 90d2c7e3f5e9..ba69b86f1c7d 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -708,6 +708,7 @@ const struct proto_ops inet6_stream_ops = { .splice_eof = inet_splice_eof, .sendmsg_locked = tcp_sendmsg_locked, .splice_read = tcp_splice_read, + .set_peek_off = sk_set_peek_off, .read_sock = tcp_read_sock, .read_skb = tcp_read_skb, .peek_len = tcp_peek_len,

From: Jon Maloy jmaloy@redhat.com

We add a selftest to check that the new feature added in commit 05ea491641d3 ("tcp: add support for SO_PEEK_OFF socket option") works correctly.

Reviewed-by: Jason Xing kerneljasonxing@gmail.com Reviewed-by: Stefano Brivio sbrivio@redhat.com Tested-by: Stefano Brivio sbrivio@redhat.com Signed-off-by: Jon Maloy jmaloy@redhat.com

--- v2: Made correction based on Jason Xing's comment. v3: Removed redundant whitespace at end of file. Based on comment from Jakub Kicinski. --- tools/testing/selftests/net/Makefile | 1 + tools/testing/selftests/net/tcp_so_peek_off.c | 183 ++++++++++++++++++ 2 files changed, 184 insertions(+) create mode 100644 tools/testing/selftests/net/tcp_so_peek_off.c

diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile index 8eaffd7a641c..1179e3261bef 100644 --- a/tools/testing/selftests/net/Makefile +++ b/tools/testing/selftests/net/Makefile @@ -80,6 +80,7 @@ TEST_PROGS += io_uring_zerocopy_tx.sh TEST_GEN_FILES += bind_bhash TEST_GEN_PROGS += sk_bind_sendto_listen TEST_GEN_PROGS += sk_connect_zero_addr +TEST_GEN_PROGS += tcp_so_peek_off TEST_PROGS += test_ingress_egress_chaining.sh TEST_GEN_PROGS += so_incoming_cpu TEST_PROGS += sctp_vrf.sh diff --git a/tools/testing/selftests/net/tcp_so_peek_off.c b/tools/testing/selftests/net/tcp_so_peek_off.c new file mode 100644 index 000000000000..df8a39d9d3c3 --- /dev/null +++ b/tools/testing/selftests/net/tcp_so_peek_off.c @@ -0,0 +1,183 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <errno.h> +#include <sys/types.h> +#include <netinet/in.h> +#include <arpa/inet.h> +#include "../kselftest.h" + +static char *afstr(int af) +{ + return af == AF_INET ? "TCP/IPv4" : "TCP/IPv6"; +} + +int tcp_peek_offset_probe(sa_family_t af) +{ + int optv = 0; + int ret = 0; + int s; + + s = socket(af, SOCK_STREAM | SOCK_CLOEXEC, IPPROTO_TCP); + if (s < 0) { + ksft_perror("Temporary TCP socket creation failed"); + } else { + if (!setsockopt(s, SOL_SOCKET, SO_PEEK_OFF, &optv, sizeof(int))) + ret = 1; + else + printf("%s does not support SO_PEEK_OFF\n", afstr(af)); + close(s); + } + return ret; +} + +static void tcp_peek_offset_set(int s, int offset) +{ + if (setsockopt(s, SOL_SOCKET, SO_PEEK_OFF, &offset, sizeof(offset))) + ksft_perror("Failed to set SO_PEEK_OFF value\n"); +} + +static int tcp_peek_offset_get(int s) +{ + int offset; + socklen_t len = sizeof(offset); + + if (getsockopt(s, SOL_SOCKET, SO_PEEK_OFF, &offset, &len)) + ksft_perror("Failed to get SO_PEEK_OFF value\n"); + return offset; +} + +static int tcp_peek_offset_test(sa_family_t af) +{ + union { + struct sockaddr sa; + struct sockaddr_in a4; + struct sockaddr_in6 a6; + } a; + int res = 0; + int s[2] = {0, 0}; + int recv_sock = 0; + int offset = 0; + ssize_t len; + char buf; + + memset(&a, 0, sizeof(a)); + a.sa.sa_family = af; + + s[0] = socket(af, SOCK_STREAM, IPPROTO_TCP); + s[1] = socket(af, SOCK_STREAM | SOCK_NONBLOCK, IPPROTO_TCP); + + if (s[0] < 0 || s[1] < 0) { + ksft_perror("Temporary socket creation failed\n"); + goto out; + } + if (bind(s[0], &a.sa, sizeof(a)) < 0) { + ksft_perror("Temporary socket bind() failed\n"); + goto out; + } + if (getsockname(s[0], &a.sa, &((socklen_t) { sizeof(a) })) < 0) { + ksft_perror("Temporary socket getsockname() failed\n"); + goto out; + } + if (listen(s[0], 0) < 0) { + ksft_perror("Temporary socket listen() failed\n"); + goto out; + } + if (connect(s[1], &a.sa, sizeof(a)) >= 0 || errno != EINPROGRESS) { + ksft_perror("Temporary socket connect() failed\n"); + goto out; + } + recv_sock = accept(s[0], NULL, NULL); + if (recv_sock <= 0) { + ksft_perror("Temporary socket accept() failed\n"); + goto out; + } + + /* Some basic tests of getting/setting offset */ + offset = tcp_peek_offset_get(recv_sock); + if (offset != -1) { + ksft_perror("Initial value of socket offset not -1\n"); + goto out; + } + tcp_peek_offset_set(recv_sock, 0); + offset = tcp_peek_offset_get(recv_sock); + if (offset != 0) { + ksft_perror("Failed to set socket offset to 0\n"); + goto out; + } + + /* Transfer a message */ + if (send(s[1], (char *)("ab"), 2, 0) <= 0 || errno != EINPROGRESS) { + ksft_perror("Temporary probe socket send() failed\n"); + goto out; + } + /* Read first byte */ + len = recv(recv_sock, &buf, 1, MSG_PEEK); + if (len != 1 || buf != 'a') { + ksft_perror("Failed to read first byte of message\n"); + goto out; + } + offset = tcp_peek_offset_get(recv_sock); + if (offset != 1) { + ksft_perror("Offset not forwarded correctly at first byte\n"); + goto out; + } + /* Try to read beyond last byte */ + len = recv(recv_sock, &buf, 2, MSG_PEEK); + if (len != 1 || buf != 'b') { + ksft_perror("Failed to read last byte of message\n"); + goto out; + } + offset = tcp_peek_offset_get(recv_sock); + if (offset != 2) { + ksft_perror("Offset not forwarded correctly at last byte\n"); + goto out; + } + /* Flush message */ + len = recv(recv_sock, NULL, 2, MSG_TRUNC); + if (len != 2) { + ksft_perror("Failed to flush message\n"); + goto out; + } + offset = tcp_peek_offset_get(recv_sock); + if (offset != 0) { + ksft_perror("Offset not reverted correctly after flush\n"); + goto out; + } + + printf("%s with MSG_PEEK_OFF works correctly\n", afstr(af)); + res = 1; +out: + if (recv_sock >= 0) + close(recv_sock); + if (s[1] >= 0) + close(s[1]); + if (s[0] >= 0) + close(s[0]); + return res; +} + +int main(void) +{ + int res4, res6; + + res4 = tcp_peek_offset_probe(AF_INET); + res6 = tcp_peek_offset_probe(AF_INET6); + + if (!res4 && !res6) + return KSFT_SKIP; + + if (res4) + res4 = tcp_peek_offset_test(AF_INET); + + if (res6) + res6 = tcp_peek_offset_test(AF_INET6); + + if (!res4 || !res6) + return KSFT_FAIL; + + return KSFT_PASS; +}