Stop trying to be clever with sysconf(_SC_NGROUPS_MAX).
The test failed the first time someone ran it as a non-root user.
Definitely not worth changing sepolicy for this, and even if we did,
that wouldn't work for static binaries (to the extent that we care).
Bug: http://b/326189243
Test: treehugger
Change-Id: I02441ce7f69ac477b0223565ac490046cee12579
diff --git a/libc/bionic/sysconf.cpp b/libc/bionic/sysconf.cpp
index ff72b93..9ffb58e 100644
--- a/libc/bionic/sysconf.cpp
+++ b/libc/bionic/sysconf.cpp
@@ -41,16 +41,6 @@
#include "platform/bionic/page.h"
#include "private/bionic_tls.h"
-static long __sysconf_fread_long(const char* path) {
- long result = 0;
- FILE* fp = fopen(path, "re");
- if (fp != nullptr) {
- fscanf(fp, "%ld", &result);
- fclose(fp);
- }
- return result;
-}
-
struct sysconf_cache {
long size, assoc, linesize;
@@ -100,6 +90,16 @@
#else
+static long __sysconf_fread_long(const char* path) {
+ long result = 0;
+ FILE* fp = fopen(path, "re");
+ if (fp != nullptr) {
+ fscanf(fp, "%ld", &result);
+ fclose(fp);
+ }
+ return result;
+}
+
static sysconf_caches* __sysconf_caches() {
static sysconf_caches cached = []{
sysconf_caches info = {};
@@ -182,8 +182,8 @@
case _SC_AVPHYS_PAGES: return get_avphys_pages();
case _SC_CHILD_MAX: return __sysconf_rlimit(RLIMIT_NPROC);
- case _SC_CLK_TCK: return static_cast<long>(getauxval(AT_CLKTCK));
- case _SC_NGROUPS_MAX: return __sysconf_fread_long("/proc/sys/kernel/ngroups_max");
+ case _SC_CLK_TCK:
+ return static_cast<long>(getauxval(AT_CLKTCK));
case _SC_NPROCESSORS_CONF: return get_nprocs_conf();
case _SC_NPROCESSORS_ONLN: return get_nprocs();
case _SC_OPEN_MAX: return __sysconf_rlimit(RLIMIT_NOFILE);
@@ -205,6 +205,11 @@
case _SC_COLL_WEIGHTS_MAX: return _POSIX2_COLL_WEIGHTS_MAX; // Minimum requirement.
case _SC_EXPR_NEST_MAX: return _POSIX2_EXPR_NEST_MAX; // Minimum requirement.
case _SC_LINE_MAX: return _POSIX2_LINE_MAX; // Minimum requirement.
+ case _SC_NGROUPS_MAX:
+ // Only root can read /proc/sys/kernel/ngroups_max on Android, and groups
+ // are vestigial anyway, so the "maximum maximum" of NGROUPS_MAX is a good
+ // enough answer for _SC_NGROUPS_MAX...
+ return NGROUPS_MAX;
case _SC_PASS_MAX: return PASS_MAX;
case _SC_2_C_BIND: return _POSIX2_C_BIND;
case _SC_2_C_DEV: return _POSIX2_C_DEV;