From: Thomas Weißschuh <thomas@t-8ch.de>
Date: Wed, 21 Dec 2022 13:42:05 +0000 (+0000)
Subject: setarch: use kernel address size if possible
X-Git-Tag: v2.39-rc1~358^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=035fc2d9c2fa6f5ff71c94e10045f62b0716b12d;p=thirdparty%2Futil-linux.git

setarch: use kernel address size if possible

If setarch is running as 32bit userspace on a 64bit kernel we should use
the kernel personality.
---

diff --git a/meson.build b/meson.build
index 38e59bd9ae..ae91338b43 100644
--- a/meson.build
+++ b/meson.build
@@ -1439,6 +1439,7 @@ exe = executable(
   'setarch',
   setarch_sources,
   include_directories : includes,
+  link_with : [lib_common],
   install_dir : usrbin_exec_dir,
   install : true)
 exes += exe
diff --git a/sys-utils/Makemodule.am b/sys-utils/Makemodule.am
index 22047d9bd4..a0bf6cb7b0 100644
--- a/sys-utils/Makemodule.am
+++ b/sys-utils/Makemodule.am
@@ -231,6 +231,7 @@ usrbin_exec_PROGRAMS += setarch
 MANPAGES += sys-utils/setarch.8
 dist_noinst_DATA += sys-utils/setarch.8.adoc
 setarch_SOURCES = sys-utils/setarch.c
+setarch_LDADD = $(LDADD) libcommon.la
 
 SETARCH_LINKS = uname26 linux32 linux64
 
diff --git a/sys-utils/setarch.c b/sys-utils/setarch.c
index b86be1e29d..d6789d05e8 100644
--- a/sys-utils/setarch.c
+++ b/sys-utils/setarch.c
@@ -35,6 +35,7 @@
 #include "nls.h"
 #include "c.h"
 #include "closestream.h"
+#include "sysfs.h"
 
 #ifndef HAVE_PERSONALITY
 # include <syscall.h>
@@ -232,7 +233,9 @@ static struct arch_domain *init_arch_domains(void)
 		if (!strcmp(un.machine, transitions[i].target_arch))
 			break;
 	if (transitions[i].perval < 0) {
-		unsigned long wrdsz = CHAR_BIT * sizeof(void *);
+		int wrdsz = sysfs_get_address_bits(NULL);
+		if (wrdsz < 0)
+			wrdsz = CHAR_BIT * sizeof(void *);
 		if (wrdsz == 32 || wrdsz == 64) {
 			/* fill up the place holder */
 			transitions[i].perval = wrdsz == 32 ? PER_LINUX32 : PER_LINUX;