495d2d8133
GCC's -Wall includes -Wsign-compare while clang does not. Since BPF programs are built with clang we need to add this flag explicitly to catch problematic comparisons like: int i = -1; unsigned int j = 1; if (i < j) // this is false. long i = -1; unsigned int j = 1; if (i < j) // this is true. C standard for reference: - If either operand is unsigned long the other shall be converted to unsigned long. - Otherwise, if one operand is a long int and the other unsigned int, then if a long int can represent all the values of an unsigned int, the unsigned int shall be converted to a long int; otherwise both operands shall be converted to unsigned long int. - Otherwise, if either operand is long, the other shall be converted to long. - Otherwise, if either operand is unsigned, the other shall be converted to unsigned. Unfortunately clang's -Wsign-compare is very noisy. It complains about (s32)a == (u32)b which is safe and doen't have surprising behavior. This patch fixes some of the issues. It needs a follow up to fix the rest. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/bpf/20231226191148.48536-2-alexei.starovoitov@gmail.com
70 lines
1.3 KiB
C
70 lines
1.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
|
|
/*
|
|
* Copyright 2021 Google LLC.
|
|
*/
|
|
|
|
#include <errno.h>
|
|
#include <linux/bpf.h>
|
|
#include <bpf/bpf_helpers.h>
|
|
|
|
__u32 invocations = 0;
|
|
__u32 assertion_error = 0;
|
|
__u32 retval_value = 0;
|
|
__s32 page_size = 0;
|
|
|
|
SEC("cgroup/setsockopt")
|
|
int get_retval(struct bpf_sockopt *ctx)
|
|
{
|
|
retval_value = bpf_get_retval();
|
|
__sync_fetch_and_add(&invocations, 1);
|
|
|
|
/* optval larger than PAGE_SIZE use kernel's buffer. */
|
|
if (ctx->optlen > page_size)
|
|
ctx->optlen = 0;
|
|
|
|
return 1;
|
|
}
|
|
|
|
SEC("cgroup/setsockopt")
|
|
int set_eunatch(struct bpf_sockopt *ctx)
|
|
{
|
|
__sync_fetch_and_add(&invocations, 1);
|
|
|
|
if (bpf_set_retval(-EUNATCH))
|
|
assertion_error = 1;
|
|
|
|
/* optval larger than PAGE_SIZE use kernel's buffer. */
|
|
if (ctx->optlen > page_size)
|
|
ctx->optlen = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
SEC("cgroup/setsockopt")
|
|
int set_eisconn(struct bpf_sockopt *ctx)
|
|
{
|
|
__sync_fetch_and_add(&invocations, 1);
|
|
|
|
if (bpf_set_retval(-EISCONN))
|
|
assertion_error = 1;
|
|
|
|
/* optval larger than PAGE_SIZE use kernel's buffer. */
|
|
if (ctx->optlen > page_size)
|
|
ctx->optlen = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
SEC("cgroup/setsockopt")
|
|
int legacy_eperm(struct bpf_sockopt *ctx)
|
|
{
|
|
__sync_fetch_and_add(&invocations, 1);
|
|
|
|
/* optval larger than PAGE_SIZE use kernel's buffer. */
|
|
if (ctx->optlen > page_size)
|
|
ctx->optlen = 0;
|
|
|
|
return 0;
|
|
}
|