diff --git a/SOURCES/oddjob-cve-2020-10737-reversal-option.patch b/SOURCES/oddjob-cve-2020-10737-reversal-option.patch new file mode 100644 index 0000000..fa187bb --- /dev/null +++ b/SOURCES/oddjob-cve-2020-10737-reversal-option.patch @@ -0,0 +1,113 @@ +From 71b0389fbb31833d827f5f0fec18880c2f602753 Mon Sep 17 00:00:00 2001 +From: Alexander Bokovoy +Date: Thu, 19 May 2022 13:52:22 +0300 +Subject: [PATCH] mkhomedir: add support for pre-CVE-2020-10737 behavior + +Pre-CVE-2020-10737 behavior was used to allow creating home directories +on NFS mounts when non-Kerberos authentication method is in use. This is +exactly the case where a race condition addressed by the CVE-2020-10737 +fix could have happened. However, there are legit use cases where this +setup is needed. + +Add '-f' option to mkhomedir helper to activate previous behavior. In +order to enable it, a change to oddjobd-mkhomedir.conf configuration +file is needed by explicitly adding '-f' option to the executable file +definition. + +Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2050079 + +Signed-off-by: Alexander Bokovoy +--- + src/mkhomedir.c | 16 +++++++++++++--- + src/oddjobd-mkhomedir.conf.5.in | 9 +++++++++ + 2 files changed, 22 insertions(+), 3 deletions(-) + +diff --git a/src/mkhomedir.c b/src/mkhomedir.c +index be85959..ac813a9 100644 +--- a/src/mkhomedir.c ++++ b/src/mkhomedir.c +@@ -53,9 +53,11 @@ static const char *skel; + static const char *skel_dir; + static struct passwd *pwd; + static mode_t override_umask; ++static int owner_mkdir_first = 0; + + #define FLAG_POPULATE (1 << 0) + #define FLAG_QUIET (1 << 1) ++#define FLAG_OWNER_MKDIR_FIRST (1 << 2) + + /* Given the path of an item somewhere in the skeleton directory, create as + * identical as possible a copy in the destination tree. */ +@@ -158,7 +160,7 @@ copy_single_item(const char *source, const struct stat *sb, + * target user just yet to avoid potential race conditions + * involving symlink attacks when we copy over the skeleton + * tree. */ +- if (status->level == 0) { ++ if (status->level == 0 && !owner_mkdir_first) { + uid = 0; + gid = 0; + } +@@ -222,6 +224,9 @@ mkhomedir(const char *user, int flags) + pwd->pw_dir); + return HANDLER_INVALID_INVOCATION; + } ++ if (flags & FLAG_OWNER_MKDIR_FIRST) { ++ owner_mkdir_first = 1; ++ } + if ((lstat(pwd->pw_dir, &st) == -1) && (errno == ENOENT)) { + /* Figure out which location we're using as a + * template. */ +@@ -237,7 +242,7 @@ mkhomedir(const char *user, int flags) + int res = nftw(get_skel_dir(), copy_single_item, 5, + FTW_PHYS); + /* only now give ownership to the target user */ +- if (res == 0) { ++ if (res == 0 && !owner_mkdir_first) { + res = chown(pwd->pw_dir, pwd->pw_uid, pwd->pw_gid); + } + +@@ -317,8 +322,11 @@ main(int argc, char **argv) + umask(override_umask); + skel_dir = "/etc/skel"; + +- while ((i = getopt(argc, argv, "nqs:u:")) != -1) { ++ while ((i = getopt(argc, argv, "nqfs:u:")) != -1) { + switch (i) { ++ case 'f': ++ flags |= FLAG_OWNER_MKDIR_FIRST; ++ break; + case 'n': + flags &= ~FLAG_POPULATE; + break; +@@ -339,6 +347,8 @@ main(int argc, char **argv) + break; + default: + fprintf(stderr, "Valid options:\n" ++ "-f\tCreate home directory initially owned by user, " ++ "not root. See man page for security issues.\n" + "-n\tDo not populate home directories, " + "just create them.\n" + "-q\tDo not print messages when creating " +diff --git a/src/oddjobd-mkhomedir.conf.5.in b/src/oddjobd-mkhomedir.conf.5.in +index d7a2429..6e35ad5 100644 +--- a/src/oddjobd-mkhomedir.conf.5.in ++++ b/src/oddjobd-mkhomedir.conf.5.in +@@ -10,6 +10,15 @@ directory. + + The mkhomedir helper itself accepts these options: + .TP ++-f ++Restore behavior before CVE-2020-10737 was fixed: create the home directory ++with user's ownership directly rather than create it as a root and only after ++populating it change to the user's ownership. The former behavior is insecure ++but may be used to allow creation of NFS-mounted home directories when ++non-Kerberos authentication is in use. It is prone for a race condition that ++could be exploited in the NFS-mounted home directories use case. To avoid ++CVE-2020-10737, do not use \fB-f\fR option in production environments. ++.TP + -q + Refrain from outputting the usual "Creating home directory..." message when it + creates a home directory. +-- +2.37.1 + diff --git a/SPECS/oddjob.spec b/SPECS/oddjob.spec index d850358..85bfb20 100644 --- a/SPECS/oddjob.spec +++ b/SPECS/oddjob.spec @@ -22,9 +22,10 @@ Name: oddjob Version: 0.34.7 -Release: 1%{?dist} +Release: 2%{?dist} Source0: https://releases.pagure.org/oddjob/oddjob-%{version}.tar.gz Source1: https://releases.pagure.org/oddjob/oddjob-%{version}.tar.gz.asc +Patch0: oddjob-cve-2020-10737-reversal-option.patch Summary: A D-Bus service which runs odd jobs on behalf of client applications License: BSD @@ -91,6 +92,7 @@ This package contains a trivial sample oddjob service. %prep %setup -q +%patch0 -p1 %build sample_flag= @@ -250,6 +252,10 @@ fi exit 0 %changelog +* Wed Aug 17 2022 Alexander Bokovoy - 0.34.7-2 +- Add a non-default option to revert behavior for CVE-2020-10737 fix +- Resolved: rhbz#2050079 + * Mon Dec 14 18:38:43 EET 2020 Alexander Bokovoy - 0.34.7-1 - Upstream release 0.34.7 - Force LC_ALL=C.UTF-8 in oddjobd systemd service environment