components/sysutils/qemu/patches/0010-Drop-unnecessary-privileges.patch

   1 From 1e3883563faf35dea24bdd07d08d5659211bdeb5 Mon Sep 17 00:00:00 2001
   2 From: Andy Fiddaman <illumos@fiddaman.net>
   3 Date: Fri, 30 Dec 2022 18:06:57 +0000
   4 Subject: Drop unnecessary privileges
   5
   6 ---
   7  os-posix.c | 41 +++++++++++++++++++++++++++++++++++++++++
   8  1 file changed, 41 insertions(+)
   9
  10 diff --git a/os-posix.c b/os-posix.c
  11 index 4858650c3e..26b7741023 100644
  12 --- a/os-posix.c
  13 +++ b/os-posix.c
  14 @@ -28,6 +28,7 @@
  15  #include <pwd.h>
  16  #include <grp.h>
  17  #include <libgen.h>
  18 +#include <priv.h>
  19
  20  /* Needed early for CONFIG_BSD etc. */
  21  #include "net/slirp.h"
  22 @@ -263,6 +264,45 @@ void os_daemonize(void)
  23      }
  24  }
  25
  26 +/*
  27 + * In case qemu is started as root, drop unnecessary privileges.
  28 + */
  29 +static void
  30 +illumos_drop_privileges(void)
  31 +{
  32 +       priv_set_t *privs, *wantedprivs;
  33 +
  34 +       privs = priv_allocset();
  35 +       wantedprivs = priv_allocset();
  36 +
  37 +       if (privs == NULL || wantedprivs == NULL) {
  38 +               error_report("Unable to allocate privilege sets");
  39 +               exit(1);
  40 +       }
  41 +
  42 +       if (getppriv(PRIV_PERMITTED, privs) != 0) {
  43 +               error_report("Failed to retrieve current privileges");
  44 +               exit(1);
  45 +       }
  46 +
  47 +       priv_basicset(wantedprivs);
  48 +       priv_delset(wantedprivs, PRIV_FILE_LINK_ANY);
  49 +       priv_delset(wantedprivs, PRIV_PROC_INFO);
  50 +       priv_delset(wantedprivs, PRIV_PROC_SESSION);
  51 +       priv_addset(wantedprivs, PRIV_NET_RAWACCESS); /* VNIC net backend */
  52 +       priv_intersect(wantedprivs, privs);
  53 +
  54 +       if (setppriv(PRIV_SET, PRIV_PERMITTED, privs) != 0 ||
  55 +           setppriv(PRIV_SET, PRIV_INHERITABLE, privs) != 0 ||
  56 +           setppriv(PRIV_SET, PRIV_LIMIT, privs) != 0) {
  57 +               error_report("Failed to reduce privileges");
  58 +               exit(1);
  59 +       }
  60 +
  61 +       priv_freeset(wantedprivs);
  62 +       priv_freeset(privs);
  63 +}
  64 +
  65  void os_setup_post(void)
  66  {
  67      int fd = 0;
  68 @@ -280,6 +320,7 @@ void os_setup_post(void)
  69
  70      change_root();
  71      change_process_uid();
  72 +    illumos_drop_privileges();
  73
  74      if (daemonize) {
  75          uint8_t status = 0;