tests/uid: import uid overflow check from tests/uid16
* tests/uid.c (main): Skip if the uid returned by getuid matches
/proc/sys/kernel/overflowuid.
diff --git a/tests/uid.c b/tests/uid.c
index f316d80..bf4d8d2 100644
--- a/tests/uid.c
+++ b/tests/uid.c
@@ -4,6 +4,7 @@
#include <assert.h>
#include <stdlib.h>
#include <unistd.h>
+#include <fcntl.h>
#include <sys/syscall.h>
int
@@ -24,6 +25,21 @@
# define __NR_getuid __NR_getxuid
#endif
uid = syscall(__NR_getuid);
+
+ (void) close(0);
+ if (open("/proc/sys/kernel/overflowuid", O_RDONLY) == 0) {
+ /* we trust the kernel */
+ char buf[sizeof(int)*3];
+ int n = read(0, buf, sizeof(buf) - 1);
+ if (n) {
+ buf[n] = '\0';
+ n = atoi(buf);
+ if (uid == n)
+ return 77;
+ }
+ (void) close(0);
+ }
+
assert(syscall(__NR_setuid, uid) == 0);
{
/*