selftests/bpf: Fix sign-extension in test fill_link_info

guidosarducci · guidosarducci · commit ac0eaedf8178 · 2025-09-20T23:16:20.000-07:00
The function verify_perf_link_info() accepts a 'long' address to perform validation, which can sign-extend on 32-bit systems and fail checks. Use an 'unsigned long' type to avoid errors like: test_fill_link_info:PASS:skel_open 0 nsec test_fill_link_info:PASS:load_kallsyms 0 nsec test_kprobe_fill_link_info:PASS:attach_kprobe 0 nsec verify_perf_link_info:PASS:get_link_info 0 nsec verify_perf_link_info:PASS:link_type 0 nsec verify_perf_link_info:PASS:perf_type_match 0 nsec verify_perf_link_info:PASS:kprobe_offset 0 nsec verify_perf_link_info:FAIL:kprobe_addr unexpected kprobe_addr: actual 3231513376 != expected -1063453920 verify_perf_link_info:PASS:kprobe_cookie 0 nsec verify_perf_link_info:PASS:name_len 0 nsec verify_perf_link_info:PASS:get_link_info 0 nsec verify_perf_link_info:PASS:link_type 0 nsec verify_perf_link_info:PASS:perf_type_match 0 nsec verify_perf_link_info:PASS:kprobe_offset 0 nsec verify_perf_link_info:FAIL:kprobe_addr unexpected kprobe_addr: actual 3231513376 != expected -1063453920 verify_perf_link_info:PASS:kprobe_cookie 0 nsec verify_perf_link_info:PASS:name_len 0 nsec verify_perf_link_info:PASS:cmp_kprobe_func_name 0 nsec test_kprobe_fill_link_info:PASS:verify_perf_link_info 0 nsec kernel-patches#109/1 fill_link_info/kprobe_link_info:FAIL [...] kernel-patches#109/2 fill_link_info/kretprobe_link_info:FAIL kernel-patches#109 fill_link_info:FAIL Fixes: 23cf7aa ("selftests/bpf: Add selftest for fill_link_info") Signed-off-by: Tony Ambardar <tony.ambardar@gmail.com>
diff --git a/tools/testing/selftests/bpf/prog_tests/fill_link_info.c b/tools/testing/selftests/bpf/prog_tests/fill_link_info.c
@@ -34,7 +34,7 @@ static noinline void uprobe_func(void)
 
 #define PERF_EVENT_COOKIE 0xdeadbeef
 
-static int verify_perf_link_info(int fd, enum bpf_perf_event_type type, long addr,
+static int verify_perf_link_info(int fd, enum bpf_perf_event_type type, unsigned long addr,
 				 ssize_t offset, ssize_t entry_offset)
 {
 	ssize_t ref_ctr_offset = entry_offset /* ref_ctr_offset for uprobes */;

Original file line number	Diff line number	Diff line change
`@@ -34,7 +34,7 @@ static noinline void uprobe_func(void)`
`34`	`34`
`35`	`35`	`#define PERF_EVENT_COOKIE 0xdeadbeef`
`36`	`36`
`37`		`-static int verify_perf_link_info(int fd, enum bpf_perf_event_type type, long addr,`
	`37`	`+static int verify_perf_link_info(int fd, enum bpf_perf_event_type type, unsigned long addr,`
`38`	`38`	`ssize_t offset, ssize_t entry_offset)`
`39`	`39`	`{`
`40`	`40`	`ssize_t ref_ctr_offset = entry_offset /* ref_ctr_offset for uprobes */;`