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0b20933d8c
Reliably remove all the type modifiers from read-only (.rodata) global
variable definitions, including cases of inner field const modifiers and
arrays of const values.
Also modify one of selftests to ensure that const volatile struct doesn't
prevent user-space from modifying .rodata variable.
Fixes: 985ead416d ("bpftool: Add skeleton codegen command")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200713232409.3062144-3-andriin@fb.com
60 lines
985 B
C
60 lines
985 B
C
// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2019 Facebook */
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#include <stdbool.h>
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#include <linux/bpf.h>
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#include <bpf/bpf_helpers.h>
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struct s {
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int a;
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long long b;
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} __attribute__((packed));
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/* .data section */
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int in1 = -1;
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long long in2 = -1;
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/* .bss section */
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char in3 = '\0';
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long long in4 __attribute__((aligned(64))) = 0;
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struct s in5 = {};
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/* .rodata section */
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const volatile struct {
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const int in6;
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} in = {};
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/* .data section */
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int out1 = -1;
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long long out2 = -1;
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/* .bss section */
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char out3 = 0;
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long long out4 = 0;
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int out6 = 0;
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extern bool CONFIG_BPF_SYSCALL __kconfig;
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extern int LINUX_KERNEL_VERSION __kconfig;
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bool bpf_syscall = 0;
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int kern_ver = 0;
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SEC("raw_tp/sys_enter")
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int handler(const void *ctx)
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{
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static volatile struct s out5;
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out1 = in1;
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out2 = in2;
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out3 = in3;
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out4 = in4;
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out5 = in5;
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out6 = in.in6;
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bpf_syscall = CONFIG_BPF_SYSCALL;
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kern_ver = LINUX_KERNEL_VERSION;
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return 0;
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}
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char _license[] SEC("license") = "GPL";
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