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author | 2021-08-23 19:43:50 -0700 | |
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committer | 2021-08-25 10:37:05 -0700 | |
commit | 576d47bb1a926fe8162253e0bca28e9bede8cf48 (patch) | |
tree | e5b1620463dac99be057e44cb7803dc7a512eada /tools | |
parent | bpf: Add bpf_task_pt_regs() helper (diff) | |
download | linux-576d47bb1a926fe8162253e0bca28e9bede8cf48.tar.gz linux-576d47bb1a926fe8162253e0bca28e9bede8cf48.tar.bz2 linux-576d47bb1a926fe8162253e0bca28e9bede8cf48.zip |
bpf: selftests: Add bpf_task_pt_regs() selftest
This test retrieves the uprobe's pt_regs in two different ways and
compares the contents in an arch-agnostic way.
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/5581eb8800f6625ec8813fe21e9dce1fbdef4937.1629772842.git.dxu@dxuuu.xyz
Diffstat (limited to 'tools')
-rw-r--r-- | tools/testing/selftests/bpf/prog_tests/task_pt_regs.c | 47 | ||||
-rw-r--r-- | tools/testing/selftests/bpf/progs/test_task_pt_regs.c | 29 |
2 files changed, 76 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/task_pt_regs.c b/tools/testing/selftests/bpf/prog_tests/task_pt_regs.c new file mode 100644 index 000000000000..53f0e0fa1a53 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/task_pt_regs.c @@ -0,0 +1,47 @@ +// SPDX-License-Identifier: GPL-2.0 +#define _GNU_SOURCE +#include <test_progs.h> +#include <linux/ptrace.h> +#include "test_task_pt_regs.skel.h" + +void test_task_pt_regs(void) +{ + struct test_task_pt_regs *skel; + struct bpf_link *uprobe_link; + size_t uprobe_offset; + ssize_t base_addr; + bool match; + + base_addr = get_base_addr(); + if (!ASSERT_GT(base_addr, 0, "get_base_addr")) + return; + uprobe_offset = get_uprobe_offset(&get_base_addr, base_addr); + + skel = test_task_pt_regs__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel_open")) + return; + if (!ASSERT_OK_PTR(skel->bss, "check_bss")) + goto cleanup; + + uprobe_link = bpf_program__attach_uprobe(skel->progs.handle_uprobe, + false /* retprobe */, + 0 /* self pid */, + "/proc/self/exe", + uprobe_offset); + if (!ASSERT_OK_PTR(uprobe_link, "attach_uprobe")) + goto cleanup; + skel->links.handle_uprobe = uprobe_link; + + /* trigger & validate uprobe */ + get_base_addr(); + + if (!ASSERT_EQ(skel->bss->uprobe_res, 1, "check_uprobe_res")) + goto cleanup; + + match = !memcmp(&skel->bss->current_regs, &skel->bss->ctx_regs, + sizeof(skel->bss->current_regs)); + ASSERT_TRUE(match, "check_regs_match"); + +cleanup: + test_task_pt_regs__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/test_task_pt_regs.c b/tools/testing/selftests/bpf/progs/test_task_pt_regs.c new file mode 100644 index 000000000000..6c059f1cfa1b --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_task_pt_regs.c @@ -0,0 +1,29 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/ptrace.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> + +struct pt_regs current_regs = {}; +struct pt_regs ctx_regs = {}; +int uprobe_res = 0; + +SEC("uprobe/trigger_func") +int handle_uprobe(struct pt_regs *ctx) +{ + struct task_struct *current; + struct pt_regs *regs; + + current = bpf_get_current_task_btf(); + regs = (struct pt_regs *) bpf_task_pt_regs(current); + __builtin_memcpy(¤t_regs, regs, sizeof(*regs)); + __builtin_memcpy(&ctx_regs, ctx, sizeof(*ctx)); + + /* Prove that uprobe was run */ + uprobe_res = 1; + + return 0; +} + +char _license[] SEC("license") = "GPL"; |