From: YiFei Zhu <zhuyifei@google.com>
Date: Thu, 16 Dec 2021 02:04:29 +0000
Subject: selftests/bpf: Update sockopt_sk test to the use bpf_set_retval
Patch-mainline: v5.18-rc1
Git-commit: 1080ef5cc0c2c3419dbdd61e441d1e014410824a
References: jsc#PED-1377
The tests would break without this patch, because at one point it calls
getsockopt(fd, SOL_TCP, TCP_ZEROCOPY_RECEIVE, &buf, &optlen)
This getsockopt receives the kernel-set -EINVAL. Prior to this patch
series, the eBPF getsockopt hook's -EPERM would override kernel's
-EINVAL, however, after this patch series, return 0's automatic
-EPERM will not; the eBPF prog has to explicitly bpf_set_retval(-EPERM)
if that is wanted.
I also removed the explicit mentions of EPERM in the comments in the
prog.
Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/4f20b77cb46812dbc2bdcd7e3fa87c7573bde55e.1639619851.git.zhuyifei@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
tools/testing/selftests/bpf/prog_tests/sockopt_sk.c | 4 +-
tools/testing/selftests/bpf/progs/sockopt_sk.c | 32 ++++++++++----------
2 files changed, 18 insertions(+), 18 deletions(-)
--- a/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c
+++ b/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c
@@ -173,11 +173,11 @@ static int getsetsockopt(void)
}
memset(&buf, 0, sizeof(buf));
- buf.zc.address = 12345; /* rejected by BPF */
+ buf.zc.address = 12345; /* Not page aligned. Rejected by tcp_zerocopy_receive() */
optlen = sizeof(buf.zc);
errno = 0;
err = getsockopt(fd, SOL_TCP, TCP_ZEROCOPY_RECEIVE, &buf, &optlen);
- if (errno != EPERM) {
+ if (errno != EINVAL) {
log_err("Unexpected getsockopt(TCP_ZEROCOPY_RECEIVE) err=%d errno=%d",
err, errno);
goto err;
--- a/tools/testing/selftests/bpf/progs/sockopt_sk.c
+++ b/tools/testing/selftests/bpf/progs/sockopt_sk.c
@@ -73,17 +73,17 @@ int _getsockopt(struct bpf_sockopt *ctx)
*/
if (optval + sizeof(struct tcp_zerocopy_receive) > optval_end)
- return 0; /* EPERM, bounds check */
+ return 0; /* bounds check */
if (((struct tcp_zerocopy_receive *)optval)->address != 0)
- return 0; /* EPERM, unexpected data */
+ return 0; /* unexpected data */
return 1;
}
if (ctx->level == SOL_IP && ctx->optname == IP_FREEBIND) {
if (optval + 1 > optval_end)
- return 0; /* EPERM, bounds check */
+ return 0; /* bounds check */
ctx->retval = 0; /* Reset system call return value to zero */
@@ -96,24 +96,24 @@ int _getsockopt(struct bpf_sockopt *ctx)
* bytes of data.
*/
if (optval_end - optval != page_size)
- return 0; /* EPERM, unexpected data size */
+ return 0; /* unexpected data size */
return 1;
}
if (ctx->level != SOL_CUSTOM)
- return 0; /* EPERM, deny everything except custom level */
+ return 0; /* deny everything except custom level */
if (optval + 1 > optval_end)
- return 0; /* EPERM, bounds check */
+ return 0; /* bounds check */
storage = bpf_sk_storage_get(&socket_storage_map, ctx->sk, 0,
BPF_SK_STORAGE_GET_F_CREATE);
if (!storage)
- return 0; /* EPERM, couldn't get sk storage */
+ return 0; /* couldn't get sk storage */
if (!ctx->retval)
- return 0; /* EPERM, kernel should not have handled
+ return 0; /* kernel should not have handled
* SOL_CUSTOM, something is wrong!
*/
ctx->retval = 0; /* Reset system call return value to zero */
@@ -152,7 +152,7 @@ int _setsockopt(struct bpf_sockopt *ctx)
/* Overwrite SO_SNDBUF value */
if (optval + sizeof(__u32) > optval_end)
- return 0; /* EPERM, bounds check */
+ return 0; /* bounds check */
*(__u32 *)optval = 0x55AA;
ctx->optlen = 4;
@@ -164,7 +164,7 @@ int _setsockopt(struct bpf_sockopt *ctx)
/* Always use cubic */
if (optval + 5 > optval_end)
- return 0; /* EPERM, bounds check */
+ return 0; /* bounds check */
memcpy(optval, "cubic", 5);
ctx->optlen = 5;
@@ -175,10 +175,10 @@ int _setsockopt(struct bpf_sockopt *ctx)
if (ctx->level == SOL_IP && ctx->optname == IP_FREEBIND) {
/* Original optlen is larger than PAGE_SIZE. */
if (ctx->optlen != page_size * 2)
- return 0; /* EPERM, unexpected data size */
+ return 0; /* unexpected data size */
if (optval + 1 > optval_end)
- return 0; /* EPERM, bounds check */
+ return 0; /* bounds check */
/* Make sure we can trim the buffer. */
optval[0] = 0;
@@ -189,21 +189,21 @@ int _setsockopt(struct bpf_sockopt *ctx)
* bytes of data.
*/
if (optval_end - optval != page_size)
- return 0; /* EPERM, unexpected data size */
+ return 0; /* unexpected data size */
return 1;
}
if (ctx->level != SOL_CUSTOM)
- return 0; /* EPERM, deny everything except custom level */
+ return 0; /* deny everything except custom level */
if (optval + 1 > optval_end)
- return 0; /* EPERM, bounds check */
+ return 0; /* bounds check */
storage = bpf_sk_storage_get(&socket_storage_map, ctx->sk, 0,
BPF_SK_STORAGE_GET_F_CREATE);
if (!storage)
- return 0; /* EPERM, couldn't get sk storage */
+ return 0; /* couldn't get sk storage */
storage->val = optval[0];
ctx->optlen = -1; /* BPF has consumed this option, don't call kernel