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Diffstat (limited to 'tools/testing/selftests/proc/proc-pid-vm.c')
-rw-r--r--tools/testing/selftests/proc/proc-pid-vm.c75
1 files changed, 68 insertions, 7 deletions
diff --git a/tools/testing/selftests/proc/proc-pid-vm.c b/tools/testing/selftests/proc/proc-pid-vm.c
index 28604c9f805c..e5962f4794f5 100644
--- a/tools/testing/selftests/proc/proc-pid-vm.c
+++ b/tools/testing/selftests/proc/proc-pid-vm.c
@@ -211,10 +211,19 @@ static int make_exe(const uint8_t *payload, size_t len)
}
#endif
-static bool g_vsyscall = false;
+/*
+ * 0: vsyscall VMA doesn't exist vsyscall=none
+ * 1: vsyscall VMA is r-xp vsyscall=emulate
+ * 2: vsyscall VMA is --xp vsyscall=xonly
+ */
+static int g_vsyscall;
+static const char *str_vsyscall;
-static const char str_vsyscall[] =
+static const char str_vsyscall_0[] = "";
+static const char str_vsyscall_1[] =
"ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]\n";
+static const char str_vsyscall_2[] =
+"ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0 [vsyscall]\n";
#ifdef __x86_64__
static void sigaction_SIGSEGV(int _, siginfo_t *__, void *___)
@@ -223,7 +232,7 @@ static void sigaction_SIGSEGV(int _, siginfo_t *__, void *___)
}
/*
- * vsyscall page can't be unmapped, probe it with memory load.
+ * vsyscall page can't be unmapped, probe it directly.
*/
static void vsyscall(void)
{
@@ -246,13 +255,52 @@ static void vsyscall(void)
act.sa_sigaction = sigaction_SIGSEGV;
(void)sigaction(SIGSEGV, &act, NULL);
+ /* gettimeofday(NULL, NULL); */
+ asm volatile (
+ "call %P0"
+ :
+ : "i" (0xffffffffff600000), "D" (NULL), "S" (NULL)
+ : "rax", "rcx", "r11"
+ );
+ exit(0);
+ }
+ waitpid(pid, &wstatus, 0);
+ if (WIFEXITED(wstatus) && WEXITSTATUS(wstatus) == 0) {
+ /* vsyscall page exists and is executable. */
+ } else {
+ /* vsyscall page doesn't exist. */
+ g_vsyscall = 0;
+ return;
+ }
+
+ pid = fork();
+ if (pid < 0) {
+ fprintf(stderr, "fork, errno %d\n", errno);
+ exit(1);
+ }
+ if (pid == 0) {
+ struct rlimit rlim = {0, 0};
+ (void)setrlimit(RLIMIT_CORE, &rlim);
+
+ /* Hide "segfault at ffffffffff600000" messages. */
+ struct sigaction act;
+ memset(&act, 0, sizeof(struct sigaction));
+ act.sa_flags = SA_SIGINFO;
+ act.sa_sigaction = sigaction_SIGSEGV;
+ (void)sigaction(SIGSEGV, &act, NULL);
+
*(volatile int *)0xffffffffff600000UL;
exit(0);
}
waitpid(pid, &wstatus, 0);
if (WIFEXITED(wstatus) && WEXITSTATUS(wstatus) == 0) {
- g_vsyscall = true;
+ /* vsyscall page is readable and executable. */
+ g_vsyscall = 1;
+ return;
}
+
+ /* vsyscall page is executable but unreadable. */
+ g_vsyscall = 2;
}
int main(void)
@@ -261,6 +309,19 @@ int main(void)
int exec_fd;
vsyscall();
+ switch (g_vsyscall) {
+ case 0:
+ str_vsyscall = str_vsyscall_0;
+ break;
+ case 1:
+ str_vsyscall = str_vsyscall_1;
+ break;
+ case 2:
+ str_vsyscall = str_vsyscall_2;
+ break;
+ default:
+ abort();
+ }
atexit(ate);
@@ -314,7 +375,7 @@ int main(void)
/* Test /proc/$PID/maps */
{
- const size_t len = strlen(buf0) + (g_vsyscall ? strlen(str_vsyscall) : 0);
+ const size_t len = strlen(buf0) + strlen(str_vsyscall);
char buf[256];
ssize_t rv;
int fd;
@@ -327,7 +388,7 @@ int main(void)
rv = read(fd, buf, sizeof(buf));
assert(rv == len);
assert(memcmp(buf, buf0, strlen(buf0)) == 0);
- if (g_vsyscall) {
+ if (g_vsyscall > 0) {
assert(memcmp(buf + strlen(buf0), str_vsyscall, strlen(str_vsyscall)) == 0);
}
}
@@ -374,7 +435,7 @@ int main(void)
assert(memmem(buf, rv, S[i], strlen(S[i])));
}
- if (g_vsyscall) {
+ if (g_vsyscall > 0) {
assert(memmem(buf, rv, str_vsyscall, strlen(str_vsyscall)));
}
}