From e71be18354391055a0a21e06a78aaade25ea62d0 Mon Sep 17 00:00:00 2001 From: Peter Korsgaard Date: Mon, 24 Aug 2020 12:25:16 +0200 Subject: [PATCH] package/trousers: add upstream security fix Fixes the following security issues: 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 For details, see the advisory: https://www.openwall.com/lists/oss-security/2020/05/20/3 Signed-off-by: Peter Korsgaard --- ...-security-issues-that-are-present-if.patch | 90 +++++++++++++++++++ package/trousers/trousers.mk | 3 + 2 files changed, 93 insertions(+) create mode 100644 package/trousers/0003-Correct-multiple-security-issues-that-are-present-if.patch diff --git a/package/trousers/0003-Correct-multiple-security-issues-that-are-present-if.patch b/package/trousers/0003-Correct-multiple-security-issues-that-are-present-if.patch new file mode 100644 index 0000000000..609245dad8 --- /dev/null +++ b/package/trousers/0003-Correct-multiple-security-issues-that-are-present-if.patch @@ -0,0 +1,90 @@ +From e74dd1d96753b0538192143adf58d04fcd3b242b Mon Sep 17 00:00:00 2001 +From: Matthias Gerstner +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 +Signed-off-by: Debora Velarde Babb +Signed-off-by: Peter Korsgaard +--- + src/tcs/ps/tcsps.c | 2 +- + src/tcsd/svrside.c | 1 + + src/tcsd/tcsd_conf.c | 10 +++++----- + 3 files changed, 7 insertions(+), 6 deletions(-) + +diff --git a/src/tcs/ps/tcsps.c b/src/tcs/ps/tcsps.c +index e47154b..85d45a9 100644 +--- a/src/tcs/ps/tcsps.c ++++ b/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)); +diff --git a/src/tcsd/svrside.c b/src/tcsd/svrside.c +index 1ae1636..1c12ff3 100644 +--- a/src/tcsd/svrside.c ++++ b/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 +diff --git a/src/tcsd/tcsd_conf.c b/src/tcsd/tcsd_conf.c +index a31503d..ea8ea13 100644 +--- a/src/tcsd/tcsd_conf.c ++++ b/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 */ +-- +2.20.1 + diff --git a/package/trousers/trousers.mk b/package/trousers/trousers.mk index 1d5364959c..5e6161ce4d 100644 --- a/package/trousers/trousers.mk +++ b/package/trousers/trousers.mk @@ -13,6 +13,9 @@ TROUSERS_INSTALL_STAGING = YES TROUSERS_AUTORECONF = YES TROUSERS_DEPENDENCIES = host-pkgconf openssl +# 0003-Correct-multiple-security-issues-that-are-present-if.patch +TROUSERS_IGNORE_CVES += CVE-2020-24330 CVE-2020-24331 CVE-2020-24332 + ifeq ($(BR2_PACKAGE_LIBICONV),y) TROUSERS_DEPENDENCIES += libiconv endif