trousers: Several Security fixes

Fixes:
CVE-2020-24332
CVE-2020-24330
CVE-2020-24331

Signed-off-by: Armin Kuster <akuster@mvista.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>

2 files changed, 95 insertions, 0 deletions

diff --git a/meta-tpm/recipes-tpm/trousers/files/0001-Correct-multiple-security-issues-that-are-present-if.patch b/meta-tpm/recipes-tpm/trousers/files/0001-Correct-multiple-security-issues-that-are-present-if.patch
new file mode 100644
index 0000000..72c81d1
--- /dev/null
+++ b/meta-tpm/recipes-tpm/trousers/files/0001-Correct-multiple-security-issues-that-are-present-if.patch
@@ -0,0 +1,94 @@
+From e74dd1d96753b0538192143adf58d04fcd3b242b Mon Sep 17 00:00:00 2001
+From: Matthias Gerstner <mgerstner@suse.de>
+Date: Fri, 14 Aug 2020 22:14:36 -0700
+Subject: [PATCH] Correct multiple security issues that are present if the tcsd
+ is started by root instead of the tss user.
+
+Patch fixes the following 3 CVEs:
+
+CVE-2020-24332
+If the tcsd daemon is started with root privileges,
+the creation of the system.data file is prone to symlink attacks
+
+CVE-2020-24330
+If the tcsd daemon is started with root privileges,
+it fails to drop the root gid after it is no longer needed
+
+CVE-2020-24331
+If the tcsd daemon is started with root privileges,
+the tss user has read and write access to the /etc/tcsd.conf file
+
+Authored-by: Matthias Gerstner <mgerstner@suse.de>
+Signed-off-by: Debora Velarde Babb <debora@linux.ibm.com>
+
+Upstream-Status: Backport
+CVE: CVE-2020-24332
+CVE: CVE-2020-24330
+CVE: CVE-2020-24331
+
+Signed-off-by: Armin Kuster <akuster@mvista.com>
+
+---
+ src/tcs/ps/tcsps.c   |  2 +-
+ src/tcsd/svrside.c   |  1 +
+ src/tcsd/tcsd_conf.c | 10 +++++-----
+ 3 files changed, 7 insertions(+), 6 deletions(-)
+
+Index: git/src/tcs/ps/tcsps.c
+===================================================================
+--- git.orig/src/tcs/ps/tcsps.c
++++ git/src/tcs/ps/tcsps.c
+@@ -72,7 +72,7 @@ get_file()
+        }
+ 
+        /* open and lock the file */
+-       system_ps_fd = open(tcsd_options.system_ps_file, O_CREAT|O_RDWR, 0600);
++       system_ps_fd = open(tcsd_options.system_ps_file, O_CREAT|O_RDWR|O_NOFOLLOW, 0600);
+        if (system_ps_fd < 0) {
+                LogError("system PS: open() of %s failed: %s",
+                                tcsd_options.system_ps_file, strerror(errno));
+Index: git/src/tcsd/svrside.c
+===================================================================
+--- git.orig/src/tcsd/svrside.c
++++ git/src/tcsd/svrside.c
+@@ -473,6 +473,7 @@ main(int argc, char **argv)
+                }
+                return TCSERR(TSS_E_INTERNAL_ERROR);
+        }
++       setgid(pwd->pw_gid);
+        setuid(pwd->pw_uid);
+ #endif
+ #endif
+Index: git/src/tcsd/tcsd_conf.c
+===================================================================
+--- git.orig/src/tcsd/tcsd_conf.c
++++ git/src/tcsd/tcsd_conf.c
+@@ -743,7 +743,7 @@ conf_file_init(struct tcsd_config *conf)
+ #ifndef SOLARIS
+        struct group *grp;
+        struct passwd *pw;
+-       mode_t mode = (S_IRUSR|S_IWUSR);
++       mode_t mode = (S_IRUSR|S_IWUSR|S_IRGRP);
+ #endif /* SOLARIS */
+        TSS_RESULT result;
+ 
+@@ -798,15 +798,15 @@ conf_file_init(struct tcsd_config *conf)
+        }
+ 
+        /* make sure user/group TSS owns the conf file */
+-       if (pw->pw_uid != stat_buf.st_uid || grp->gr_gid != stat_buf.st_gid) {
++       if (stat_buf.st_uid != 0 || grp->gr_gid != stat_buf.st_gid) {
+                LogError("TCSD config file (%s) must be user/group %s/%s", tcsd_config_file,
+-                               TSS_USER_NAME, TSS_GROUP_NAME);
++                               "root", TSS_GROUP_NAME);
+                return TCSERR(TSS_E_INTERNAL_ERROR);
+        }
+ 
+-       /* make sure only the tss user can manipulate the config file */
++       /* make sure only the tss user can read (but not manipulate) the config file */
+        if (((stat_buf.st_mode & 0777) ^ mode) != 0) {
+-               LogError("TCSD config file (%s) must be mode 0600", tcsd_config_file);
++               LogError("TCSD config file (%s) must be mode 0640", tcsd_config_file);
+                return TCSERR(TSS_E_INTERNAL_ERROR);
+        }
+ #endif /* SOLARIS */
diff --git a/meta-tpm/recipes-tpm/trousers/trousers_git.bb b/meta-tpm/recipes-tpm/trousers/trousers_git.bb
index fe8f557..95e821b 100644
--- a/meta-tpm/recipes-tpm/trousers/trousers_git.bb
+++ b/meta-tpm/recipes-tpm/trousers/trousers_git.bb
@@ -16,6 +16,7 @@ SRC_URI = " \
         file://tcsd.service \
         file://get-user-ps-path-use-POSIX-getpwent-instead-of-getpwe.patch \
         file://0001-build-don-t-override-localstatedir-mandir-sysconfdir.patch \
+        file://0001-Correct-multiple-security-issues-that-are-present-if.patch \
         "
 
 S = "${WORKDIR}/git"