Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit d8e92de8 authored by Dominik Brodowski's avatar Dominik Brodowski Committed by Ingo Molnar
Browse files

selftests/x86: Clean up and document sscanf() usage 



Replace a couple of magically connected buffer length literal constants with
a common definition that makes their relationship obvious. Also document
why our sscanf() usage is safe.

No intended functional changes.

Suggested-by: default avatarIngo Molnar <mingo@kernel.org>
Signed-off-by: default avatarDominik Brodowski <linux@dominikbrodowski.net>
Cc: Andrew Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kselftest@vger.kernel.org
Cc: shuah@kernel.org
Link: http://lkml.kernel.org/r/20180211205924.GA23210@light.dominikbrodowski.net


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 198ee8e1

tools/testing/selftests/x86/test_vdso.c

+8 −3
Original line number Original line Diff line number Diff line
@@ -26,6 +26,9 @@ 
# endif

# endif

#endif

#endif





/* max length of lines in /proc/self/maps - anything longer is skipped here */

#define MAPS_LINE_LEN 128



int nerrs = 0;

int nerrs = 0;





typedef long (*getcpu_t)(unsigned *, unsigned *, void *);

typedef long (*getcpu_t)(unsigned *, unsigned *, void *);
@@ -37,17 +40,19 @@ static void *vsyscall_getcpu(void) 
{

{

#ifdef __x86_64__

#ifdef __x86_64__

	FILE *maps;

	FILE *maps;

	char line[128];

	char line[MAPS_LINE_LEN];

	bool found = false;

	bool found = false;





	maps = fopen("/proc/self/maps", "r");

	maps = fopen("/proc/self/maps", "r");

	if (!maps) /* might still be present, but ignore it here, as we test vDSO not vsyscall */

	if (!maps) /* might still be present, but ignore it here, as we test vDSO not vsyscall */

		return NULL;

		return NULL;





	while (fgets(line, sizeof(line), maps)) {

	while (fgets(line, MAPS_LINE_LEN, maps)) {

		char r, x;

		char r, x;

		void *start, *end;

		void *start, *end;

		char name[128];

		char name[MAPS_LINE_LEN];



		/* sscanf() is safe here as strlen(name) >= strlen(line) */

		if (sscanf(line, "%p-%p %c-%cp %*x %*x:%*x %*u %s",

		if (sscanf(line, "%p-%p %c-%cp %*x %*x:%*x %*u %s",

			   &start, &end, &r, &x, name) != 5)

			   &start, &end, &r, &x, name) != 5)

			continue;

			continue;

tools/testing/selftests/x86/test_vsyscall.c

+8 −3
Original line number Original line Diff line number Diff line
@@ -33,6 +33,9 @@ 
# endif

# endif

#endif

#endif





/* max length of lines in /proc/self/maps - anything longer is skipped here */

#define MAPS_LINE_LEN 128



static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *),

static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *),

		       int flags)

		       int flags)

{

{
@@ -98,7 +101,7 @@ static int init_vsys(void) 
#ifdef __x86_64__

#ifdef __x86_64__

	int nerrs = 0;

	int nerrs = 0;

	FILE *maps;

	FILE *maps;

	char line[128];

	char line[MAPS_LINE_LEN];

	bool found = false;

	bool found = false;





	maps = fopen("/proc/self/maps", "r");

	maps = fopen("/proc/self/maps", "r");
@@ -108,10 +111,12 @@ static int init_vsys(void) 
		return 0;

		return 0;

	}

	}





	while (fgets(line, sizeof(line), maps)) {

	while (fgets(line, MAPS_LINE_LEN, maps)) {

		char r, x;

		char r, x;

		void *start, *end;

		void *start, *end;

		char name[128];

		char name[MAPS_LINE_LEN];



		/* sscanf() is safe here as strlen(name) >= strlen(line) */

		if (sscanf(line, "%p-%p %c-%cp %*x %*x:%*x %*u %s",

		if (sscanf(line, "%p-%p %c-%cp %*x %*x:%*x %*u %s",

			   &start, &end, &r, &x, name) != 5)

			   &start, &end, &r, &x, name) != 5)

			continue;

			continue;