Skip to contentSkip to conversation

Fix Yocto#5539 and Yocto#7137

PATCH New Chen Qi 1 participant 3 messages Apr 21, 2015

lore
Share & tools
lore

Chen Qi

author
#0 lore raw

cover Fix Yocto#5539 and Yocto#7137

The following changes since commit c9b06c79ed8a082d1b385e9f61721aeeda9bf1af:

init-install-efi.sh: fix gummiboot entry installation (2015-04-21 07:19:07 +0100)

are available in the git repository at:

git://git.openembedded.org/openembedded-core-contrib ChenQi/bug-5539-7137
http://cgit.openembedded.org/cgit.cgi/openembedded-core-contrib/log/?h=ChenQi/bug-5539-7137

Chen Qi (2):
shadow: fix `su' behaviour
bash: explicitly define NON_INTERACTIVE_LOGIN_SHELLS in CFLAGS

 meta/recipes-extended/bash/bash.inc                |  5 +++++
 .../0001-su.c-fix-to-exec-command-correctly.patch  | 25 ----------------------
 meta/recipes-extended/shadow/shadow.inc            |  5 ++++-
 3 files changed, 9 insertions(+), 26 deletions(-)
 delete mode 100644 meta/recipes-extended/shadow/files/0001-su.c-fix-to-exec-command-correctly.patch
Signature · 1 line
1.9.1
author
#1 lore raw

PATCH 1/2 shadow: fix `su' behaviour

0001-su.c-fix-to-exec-command-correctly.patch is removed. Below is the reason. This patch is introduced to solve the 'su: applet not found' problem when executing `su -l xxx -c env'. The patch references codes of previous release of shadow. However, this patch introduces bug#5359. So it's not correct.

Let's first look at the root cause of 'su: applet not found' problem. This problem appears when /bin/sh is provided by busybox.
When executing `su -l xxx -c env' command, the following function is invoked.

    execve("/bin/sh", ["-su", "-c", "env"], [/* 6 vars */])

Note that the argv[0] provided to new executable file (/bin/sh) is "-su". As /bin/sh is a symlink to /bin/busybox. It's /bin/busybox that is executed. In busybox's appletlib.c, it would examine argv[0], try to find an applet that has the same name, and then try to execute the main function of the applet. This logic results in `su' applet from busybox to be executed. However, we default to set 'BUSYBOX_SPLIT_SUID' to "1", so 'su' is not found. Further more, even if we set 'BUSYBOX_SPLIT_SUID' to "0", so that 'su' applet is found. The whole behaviour is still not correct. Because 'su' from shadow takes higher priority than that from busybox, so 'su' from busybox should never be executed on such system unless it's specified clearly by the end user. The logic of busybox's appletlib.c is totally correct from the point of busybox itself. It's an integration problem.

To solve the above problem, this patch comment out SU_NAME in /etc/login.defs so that the final function executed in shadow's su is as below.

    execve("/bin/sh", ["-sh", "-c", "env"], [/* 6 vars */])

[YOCTO #5359]
[YOCTO #7137]

---
 .../0001-su.c-fix-to-exec-command-correctly.patch  | 25 ----------------------
 meta/recipes-extended/shadow/shadow.inc            |  5 ++++-
 2 files changed, 4 insertions(+), 26 deletions(-)
 delete mode 100644 meta/recipes-extended/shadow/files/0001-su.c-fix-to-exec-command-correctly.patch
meta/recipes-extended/shadow/files/0001-su.c-fix-to-exec-command-correctly.patch deleted +0 -25
deleted file mode 100644
index 31337de..0000000
@@ -1,25 +0,0 @@
-Upstream-Status: Pending
-
-Subject: su.c: fix to exec command correctly
-
-Signed-off-by: Chen Qi <[email protected]>
----
- src/su.c |    2 +-
- 1 file changed, 1 insertion(+), 1 deletion(-)
-
-diff --git a/src/su.c b/src/su.c
-index 3704217..bc4f2ac 100644
---- a/src/su.c
-+++ b/src/su.c
-@@ -1156,7 +1156,7 @@ int main (int argc, char **argv)
- 		 * Use the shell and create an argv
- 		 * with the rest of the command line included.
- 		 */
--		argv[-1] = cp;
-+		argv[-1] = shellstr;
- 		execve_shell (shellstr, &argv[-1], environ);
- 		err = errno;
- 		(void) fprintf (stderr,
--- 
-1.7.9.5
-
meta/recipes-extended/shadow/shadow.inc +4 -1
index 7c63d88..5451718 100644
@@ -14,7 +14,6 @@ SRC_URI = "http://pkg-shadow.alioth.debian.org/releases/${BPN}-${PV}.tar.xz \
            file://shadow-4.1.3-dots-in-usernames.patch \
            file://usermod-fix-compilation-failure-with-subids-disabled.patch \
            file://fix-installation-failure-with-subids-disabled.patch \
-           file://0001-su.c-fix-to-exec-command-correctly.patch \
            file://0001-Do-not-read-login.defs-before-doing-chroot.patch \
            file://check_size_of_uid_t_and_gid_t_using_AC_CHECK_SIZEOF.patch \
            ${@bb.utils.contains('PACKAGECONFIG', 'pam', '${PAM_SRC_URI}', '', d)} \
@@ -108,6 +107,10 @@ do_install() {
 	# Disable checking emails.
 	sed -i 's/MAIL_CHECK_ENAB/#MAIL_CHECK_ENAB/g' ${D}${sysconfdir}/login.defs
 
+	# Comment out SU_NAME to work correctly with busybox
+	# See Bug#5359 and Bug#7173
+	sed -i 's:^SU_NAME:#SU_NAME:g' ${D}${sysconfdir}/login.defs
+
 	# Use proper encryption for passwords
 	sed -i 's/^#ENCRYPT_METHOD.*$/ENCRYPT_METHOD SHA512/' ${D}${sysconfdir}/login.defs
 
Signature · 1 line
1.9.1
author
#2 lore raw

PATCH 2/2 bash: explicitly define NON_INTERACTIVE_LOGIN_SHELLS in CFLAGS

In reply to Chen Qi

If NON_INTERACTIVE_LOGIN_SHELLS is defined, all login shells read the startup files, even if they are not interactive.

This is the behaviour of other major distros like Ubuntu and Fedora. We also need to set it so that when executing `su -l xxx -c env' command, /etc/profile is parsed.

[YOCTO #5359]
[YOCTO #7137]

---
 meta/recipes-extended/bash/bash.inc | 5 +++++
 1 file changed, 5 insertions(+)
meta/recipes-extended/bash/bash.inc +5 -0
index d7b28cf..c06f157 100644
@@ -9,6 +9,11 @@ inherit autotools gettext texinfo update-alternatives ptest
 EXTRA_AUTORECONF += "--exclude=autoheader"
 EXTRA_OECONF = "--enable-job-control"
 
+# If NON_INTERACTIVE_LOGIN_SHELLS is defined, all login shells read the
+# startup files, even if they are not interactive.
+# This is what other major distros do. And this is what we wanted. See bug#5359 and bug#7137.
+CFLAGS += "-DNON_INTERACTIVE_LOGIN_SHELLS"
+
 ALTERNATIVE_${PN} = "sh"
 ALTERNATIVE_LINK_NAME[sh] = "${base_bindir}/sh"
 ALTERNATIVE_TARGET[sh] = "${base_bindir}/bash"
Signature · 1 line
1.9.1