Public bug reported: Hello, just found a bug in selinux.
Whats going wrong: Copy a link with "-a" option while selinux is on. steps to reproduce: ~$ mkdir -p a/b ~$ ln -s b a/c ~$ cp -a a b cp: failed to restore the default file creation context: Invalid argument Results of my investigation: The "cp" of coreutils is calling "setfscreatecon (NULL)" to restore the default file creation context (coreutils-8.30/src/copy.c:1771) as it is stated in the selinux api (/libselinux/include/selinux/selinux.h:71). As we see in the result of strace below, the kernel returns an -1 on try to restore the default file creation context. So in my opinion is the bug has to be in the selinux_setprocattr method in the security/selinux/hooks.c file. Part of "strace cp -a a b" lgetxattr("a/c", "security.selinux", "system_u:object_r:user_home_dir_t:s0", 255) = 37 readlink("a/c", "b", 2) = 1 symlink("b", "b/a/c") = 0 open("/proc/self/task/2136/attr/fscreate", O_RDWR|O_CLOEXEC) = 3 write(3, NULL, 0) = -1 EINVAL (Invalid argument) close(3) = 0 open("/usr/share/locale/locale.alias", O_RDONLY|O_CLOEXEC) = 3 fstat(3, {st_mode=S_IFREG|0644, st_size=2995, ...}) = 0 read(3, "# Locale name alias data base.\n#"..., 4096) = 2995 read(3, "", 4096) = 0 close(3) ** Affects: linux (Ubuntu) Importance: Undecided Status: Confirmed ** Tags: xenial -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1794067 Title: Bug in selinux on ubuntu 16.04 with kernel 4.15.0-34 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1794067/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs