linux-kernel - [PATCH v3 3/4] selftests/mm: vm_util: Split up /proc/self/smaps parsing

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250113-virtual_address_range-tests-v3-3-f4a8e6b7feed@linutronix.de>
Date: Mon, 13 Jan 2025 14:15:37 +0100
From: Thomas Weißschuh <thomas.weissschuh@...utronix.de>
To: Andrew Morton <akpm@...ux-foundation.org>, 
 Shuah Khan <shuah@...nel.org>, Dev Jain <dev.jain@....com>, 
 Thomas Gleixner <tglx@...utronix.de>, David Hildenbrand <david@...hat.com>
Cc: linux-mm@...ck.org, linux-kselftest@...r.kernel.org, 
 linux-kernel@...r.kernel.org, 
 Thomas Weißschuh <thomas.weissschuh@...utronix.de>
Subject: [PATCH v3 3/4] selftests/mm: vm_util: Split up /proc/self/smaps
 parsing

Upcoming changes want to reuse the /proc/self/smaps parsing logic to
parse the VmFlags field.
As that works differently from the currently parsed HugePage counters,
split up the logic so common functionality can be shared.

While reworking this code, also use the correct sscanf placeholder for
the "uint64_t thp" variable.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@...utronix.de>
---
 tools/testing/selftests/mm/vm_util.c | 42 +++++++++++++++++++++++++-----------
 1 file changed, 29 insertions(+), 13 deletions(-)

diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c
index d8d0cf04bb57fd22bd7748fffec6a23c3103e35c..8468a19d6acca10c7e9228c03a935cdeb2402b5d 100644
--- a/tools/testing/selftests/mm/vm_util.c
+++ b/tools/testing/selftests/mm/vm_util.c
@@ -2,6 +2,7 @@
 #include <string.h>
 #include <fcntl.h>
 #include <dirent.h>
+#include <inttypes.h>
 #include <sys/ioctl.h>
 #include <linux/userfaultfd.h>
 #include <linux/fs.h>
@@ -193,13 +194,11 @@ unsigned long rss_anon(void)
 	return rss_anon;
 }
 
-bool __check_huge(void *addr, char *pattern, int nr_hpages,
-		  uint64_t hpage_size)
+char *__get_smap_entry(void *addr, const char *pattern, char *buf, size_t len)
 {
-	uint64_t thp = -1;
 	int ret;
 	FILE *fp;
-	char buffer[MAX_LINE_LENGTH];
+	char *entry;
 	char addr_pattern[MAX_LINE_LENGTH];
 
 	ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "%08lx-",
@@ -211,23 +210,40 @@ bool __check_huge(void *addr, char *pattern, int nr_hpages,
 	if (!fp)
 		ksft_exit_fail_msg("%s: Failed to open file %s\n", __func__, SMAP_FILE_PATH);
 
-	if (!check_for_pattern(fp, addr_pattern, buffer, sizeof(buffer)))
+	if (!check_for_pattern(fp, addr_pattern, buf, len))
 		goto err_out;
 
-	/*
-	 * Fetch the pattern in the same block and check the number of
-	 * hugepages.
-	 */
-	if (!check_for_pattern(fp, pattern, buffer, sizeof(buffer)))
+	/* Fetch the pattern in the same block */
+	if (!check_for_pattern(fp, pattern, buf, len))
 		goto err_out;
 
-	snprintf(addr_pattern, MAX_LINE_LENGTH, "%s%%9ld kB", pattern);
+	/* Trim trailing newline */
+	entry = strchr(buf, '\n');
+	if (entry)
+		*entry = '\0';
 
-	if (sscanf(buffer, addr_pattern, &thp) != 1)
-		ksft_exit_fail_msg("Reading smap error\n");
+	entry = buf + strlen(pattern);
 
 err_out:
 	fclose(fp);
+	return entry;
+}
+
+bool __check_huge(void *addr, char *pattern, int nr_hpages,
+		  uint64_t hpage_size)
+{
+	char buffer[MAX_LINE_LENGTH];
+	uint64_t thp = -1;
+	char *entry;
+
+	entry = __get_smap_entry(addr, pattern, buffer, sizeof(buffer));
+	if (!entry)
+		goto err_out;
+
+	if (sscanf(entry, "%9" SCNu64 " kB", &thp) != 1)
+		ksft_exit_fail_msg("Reading smap error\n");
+
+err_out:
 	return thp == (nr_hpages * (hpage_size >> 10));
 }
 

-- 
2.47.1