[PATCH 3/3] selftests/mm: mremap_test: Use sscanf to parse /proc/self/maps

From: Dev Jain
Date: Sat Mar 30 2024 - 13:38:27 EST


Enforce consistency across files by avoiding two separate functions to parse
/proc/self/maps, replacing them with a simple sscanf().

Signed-off-by: Dev Jain <dev.jain@xxxxxxx>
---
tools/testing/selftests/mm/mremap_test.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c
index 678c79d5b8ef..1b03bcfaefdf 100644
--- a/tools/testing/selftests/mm/mremap_test.c
+++ b/tools/testing/selftests/mm/mremap_test.c
@@ -148,19 +148,21 @@ static unsigned long long get_mmap_min_addr(void)
* Using /proc/self/maps, assert that the specified address range is contained
* within a single mapping.
*/
-static bool is_range_mapped(FILE *maps_fp, void *start, void *end)
+static bool is_range_mapped(FILE *maps_fp, unsigned long start,
+ unsigned long end)
{
char *line = NULL;
size_t len = 0;
bool success = false;
+ unsigned long first_val, second_val;

rewind(maps_fp);

while (getline(&line, &len, maps_fp) != -1) {
- char *first = strtok(line, "- ");
- void *first_val = (void *)strtol(first, NULL, 16);
- char *second = strtok(NULL, "- ");
- void *second_val = (void *) strtol(second, NULL, 16);
+ if (sscanf(line, "%lx-%lx", &first_val, &second_val) != 2) {
+ ksft_exit_fail_msg("cannot parse /proc/self/maps\n");
+ break;
+ }

if (first_val <= start && second_val >= end) {
success = true;
@@ -255,7 +257,8 @@ static void mremap_expand_merge(FILE *maps_fp, unsigned long page_size)
goto out;
}

- success = is_range_mapped(maps_fp, start, start + 3 * page_size);
+ success = is_range_mapped(maps_fp, (unsigned long)start,
+ (unsigned long)(start + 3 * page_size));
munmap(start, 3 * page_size);

out:
@@ -294,7 +297,8 @@ static void mremap_expand_merge_offset(FILE *maps_fp, unsigned long page_size)
goto out;
}

- success = is_range_mapped(maps_fp, start, start + 3 * page_size);
+ success = is_range_mapped(maps_fp, (unsigned long)start,
+ (unsigned long)(start + 3 * page_size));
munmap(start, 3 * page_size);

out:
--
2.34.1