[PATCH bpf-next 4/5] libbpf: add support for sleepable kprobe and uprobe programs

[Delyan Kratunov <delyank@xxxxxx>]

Add section mappings for uprobe.s and kprobe.s programs. The latter
cannot currently attach but they're still useful to open and load in
order to validate that prohibition.

Signed-off-by: Delyan Kratunov <delyank@xxxxxx>
---
 tools/lib/bpf/libbpf.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 9a213aaaac8a..9e89a478d40e 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -8692,9 +8692,12 @@ static const struct bpf_sec_def section_defs[] = {
 	SEC_DEF("sk_reuseport/migrate",	SK_REUSEPORT, BPF_SK_REUSEPORT_SELECT_OR_MIGRATE, SEC_ATTACHABLE | SEC_SLOPPY_PFX),
 	SEC_DEF("sk_reuseport",		SK_REUSEPORT, BPF_SK_REUSEPORT_SELECT, SEC_ATTACHABLE | SEC_SLOPPY_PFX),
 	SEC_DEF("kprobe/",		KPROBE,	0, SEC_NONE, attach_kprobe),
+	SEC_DEF("kprobe.s/",		KPROBE,	0, SEC_SLEEPABLE, attach_kprobe),
 	SEC_DEF("uprobe+",		KPROBE,	0, SEC_NONE, attach_uprobe),
+	SEC_DEF("uprobe.s+",		KPROBE,	0, SEC_SLEEPABLE, attach_uprobe),
 	SEC_DEF("kretprobe/",		KPROBE, 0, SEC_NONE, attach_kprobe),
 	SEC_DEF("uretprobe+",		KPROBE, 0, SEC_NONE, attach_uprobe),
+	SEC_DEF("uretprobe.s+",		KPROBE, 0, SEC_SLEEPABLE, attach_uprobe),
 	SEC_DEF("kprobe.multi/",	KPROBE,	BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi),
 	SEC_DEF("kretprobe.multi/",	KPROBE,	BPF_TRACE_KPROBE_MULTI, SEC_NONE, attach_kprobe_multi),
 	SEC_DEF("usdt+",		KPROBE,	0, SEC_NONE, attach_usdt),
@@ -10432,13 +10435,18 @@ static int attach_kprobe(const struct bpf_program *prog, long cookie, struct bpf
 	const char *func_name;
 	char *func;
 	int n;
+	bool sleepable = false;
 
 	opts.retprobe = str_has_pfx(prog->sec_name, "kretprobe/");
+	sleepable = str_has_pfx(prog->sec_name, "kprobe.s/");
 	if (opts.retprobe)
 		func_name = prog->sec_name + sizeof("kretprobe/") - 1;
+	else if (sleepable)
+		func_name = prog->sec_name + sizeof("kprobe.s/") - 1;
 	else
 		func_name = prog->sec_name + sizeof("kprobe/") - 1;
 
+
 	n = sscanf(func_name, "%m[a-zA-Z0-9_.]+%li", &func, &offset);
 	if (n < 1) {
 		pr_warn("kprobe name is invalid: %s\n", func_name);
@@ -10957,7 +10965,7 @@ static int attach_uprobe(const struct bpf_program *prog, long cookie, struct bpf
 		break;
 	case 3:
 	case 4:
-		opts.retprobe = strcmp(probe_type, "uretprobe") == 0;
+		opts.retprobe = str_has_pfx(probe_type, "uretprobe");
 		if (opts.retprobe && offset != 0) {
 			pr_warn("prog '%s': uretprobes do not support offset specification\n",
 				prog->name);
-- 
2.35.1