From e38774dea8d0a23b952a423b4e7a946f0f570149 Mon Sep 17 00:00:00 2001

From: Jakub Filak <jfilak@redhat.com>

Date: Fri, 17 Apr 2015 14:42:13 +0200

Subject: [PATCH] ccpp: harden dealing with UID/GID

* Don't fall back to UID 0 (fixed in libreport)

* Use fsgid.

This issue was discovered by Florian Weimer of Red Hat Product Security.

Signed-off-by: Jakub Filak <jfilak@redhat.com>

---

 src/hooks/abrt-hook-ccpp.c | 13 +++++++------

 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/hooks/abrt-hook-ccpp.c b/src/hooks/abrt-hook-ccpp.c

index 9d9f549..92413e3 100644

--- a/src/hooks/abrt-hook-ccpp.c

+++ b/src/hooks/abrt-hook-ccpp.c

@@ -163,16 +163,13 @@ static DIR *open_cwd(pid_t pid)

     return cwd;

 }

-static int open_user_core(uid_t uid, uid_t fsuid, pid_t pid, char **percent_values)

+static int open_user_core(uid_t uid, uid_t fsuid, gid_t fsgid, pid_t pid, char **percent_values)

 {

     proc_cwd = open_cwd(pid);

     if (proc_cwd == NULL)

         return -1;

-    struct passwd* pw = getpwuid(uid);

-    gid_t gid = pw ? pw->pw_gid : uid;

-    //log("setting uid: %i gid: %i", uid, gid);

-    xsetegid(gid);

+    xsetegid(fsgid);

     xseteuid(fsuid);

     if (strcmp(core_basename, "core") == 0)

@@ -525,6 +522,10 @@ int main(int argc, char** argv)

     if (tmp_fsuid < 0)

         perror_msg_and_die("Can't parse 'Uid: line' in /proc/%lu/status", (long)pid);

+    const int fsgid = get_fsgid(proc_pid_status);

+    if (fsgid < 0)

+        error_msg_and_die("Can't parse 'Gid: line' in /proc/%lu/status", (long)pid);

+

     int suid_policy = dump_suid_policy();

     if (tmp_fsuid != uid)

     {

@@ -543,7 +544,7 @@ int main(int argc, char** argv)

     int user_core_fd = -1;

     if (setting_MakeCompatCore && ulimit_c != 0)

         /* note: checks "user_pwd == NULL" inside; updates core_basename */

-        user_core_fd = open_user_core(uid, fsuid, pid, &argv[1]);

+        user_core_fd = open_user_core(uid, fsuid, fsgid, pid, &argv[1]);

     if (executable == NULL)

     {

-- 

2.1.0