1// SPDX-License-Identifier: GPL-2.0
  2#include <test_progs.h>
  3#include "test_attach_probe.skel.h"
  4
  5#if defined(__powerpc64__) && defined(_CALL_ELF) && _CALL_ELF == 2
  6
  7#define OP_RT_RA_MASK   0xffff0000UL
  8#define LIS_R2          0x3c400000UL
  9#define ADDIS_R2_R12    0x3c4c0000UL
 10#define ADDI_R2_R2      0x38420000UL
 11
 12static ssize_t get_offset(ssize_t addr, ssize_t base)
 13{
 14	u32 *insn = (u32 *) addr;
 15
 16	/*
 17	 * A PPC64 ABIv2 function may have a local and a global entry
 18	 * point. We need to use the local entry point when patching
 19	 * functions, so identify and step over the global entry point
 20	 * sequence.
 21	 *
 22	 * The global entry point sequence is always of the form:
 23	 *
 24	 * addis r2,r12,XXXX
 25	 * addi  r2,r2,XXXX
 26	 *
 27	 * A linker optimisation may convert the addis to lis:
 28	 *
 29	 * lis   r2,XXXX
 30	 * addi  r2,r2,XXXX
 31	 */
 32	if ((((*insn & OP_RT_RA_MASK) == ADDIS_R2_R12) ||
 33	     ((*insn & OP_RT_RA_MASK) == LIS_R2)) &&
 34	    ((*(insn + 1) & OP_RT_RA_MASK) == ADDI_R2_R2))
 35		return (ssize_t)(insn + 2) - base;
 36	else
 37		return addr - base;
 38}
 39#else
 40#define get_offset(addr, base) (addr - base)
 41#endif
 42
 43ssize_t get_base_addr() {
 44	size_t start, offset;
 45	char buf[256];
 46	FILE *f;
 47
 48	f = fopen("/proc/self/maps", "r");
 49	if (!f)
 50		return -errno;
 51
 52	while (fscanf(f, "%zx-%*x %s %zx %*[^\n]\n",
 53		      &start, buf, &offset) == 3) {
 54		if (strcmp(buf, "r-xp") == 0) {
 55			fclose(f);
 56			return start - offset;
 57		}
 58	}
 59
 60	fclose(f);
 61	return -EINVAL;
 62}
 63
 64void test_attach_probe(void)
 65{
 66	int duration = 0;
 67	struct bpf_link *kprobe_link, *kretprobe_link;
 68	struct bpf_link *uprobe_link, *uretprobe_link;
 69	struct test_attach_probe* skel;
 70	size_t uprobe_offset;
 71	ssize_t base_addr;
 72
 73	base_addr = get_base_addr();
 74	if (CHECK(base_addr < 0, "get_base_addr",
 75		  "failed to find base addr: %zd", base_addr))
 76		return;
 77	uprobe_offset = get_offset((size_t)&get_base_addr, base_addr);
 78
 79	skel = test_attach_probe__open_and_load();
 80	if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))
 81		return;
 82	if (CHECK(!skel->bss, "check_bss", ".bss wasn't mmap()-ed\n"))
 83		goto cleanup;
 84
 85	kprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kprobe,
 86						 false /* retprobe */,
 87						 SYS_NANOSLEEP_KPROBE_NAME);
 88	if (!ASSERT_OK_PTR(kprobe_link, "attach_kprobe"))
 89		goto cleanup;
 90	skel->links.handle_kprobe = kprobe_link;
 91
 92	kretprobe_link = bpf_program__attach_kprobe(skel->progs.handle_kretprobe,
 93						    true /* retprobe */,
 94						    SYS_NANOSLEEP_KPROBE_NAME);
 95	if (!ASSERT_OK_PTR(kretprobe_link, "attach_kretprobe"))
 96		goto cleanup;
 97	skel->links.handle_kretprobe = kretprobe_link;
 98
 99	uprobe_link = bpf_program__attach_uprobe(skel->progs.handle_uprobe,
100						 false /* retprobe */,
101						 0 /* self pid */,
102						 "/proc/self/exe",
103						 uprobe_offset);
104	if (!ASSERT_OK_PTR(uprobe_link, "attach_uprobe"))
105		goto cleanup;
106	skel->links.handle_uprobe = uprobe_link;
107
108	uretprobe_link = bpf_program__attach_uprobe(skel->progs.handle_uretprobe,
109						    true /* retprobe */,
110						    -1 /* any pid */,
111						    "/proc/self/exe",
112						    uprobe_offset);
113	if (!ASSERT_OK_PTR(uretprobe_link, "attach_uretprobe"))
114		goto cleanup;
115	skel->links.handle_uretprobe = uretprobe_link;
116
117	/* trigger & validate kprobe && kretprobe */
118	usleep(1);
119
120	if (CHECK(skel->bss->kprobe_res != 1, "check_kprobe_res",
121		  "wrong kprobe res: %d\n", skel->bss->kprobe_res))
122		goto cleanup;
123	if (CHECK(skel->bss->kretprobe_res != 2, "check_kretprobe_res",
124		  "wrong kretprobe res: %d\n", skel->bss->kretprobe_res))
125		goto cleanup;
126
127	/* trigger & validate uprobe & uretprobe */
128	get_base_addr();
129
130	if (CHECK(skel->bss->uprobe_res != 3, "check_uprobe_res",
131		  "wrong uprobe res: %d\n", skel->bss->uprobe_res))
132		goto cleanup;
133	if (CHECK(skel->bss->uretprobe_res != 4, "check_uretprobe_res",
134		  "wrong uretprobe res: %d\n", skel->bss->uretprobe_res))
135		goto cleanup;
136
137cleanup:
138	test_attach_probe__destroy(skel);
139}