diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c index be0757ecfc..da4c1e25d8 100644 --- a/tools/libxl/libxl_dm.c +++ b/tools/libxl/libxl_dm.c @@ -63,6 +63,20 @@ const char *libxl__domain_device_model(libxl__gc *gc, return dm; } +/* XSA-180 / CVE-2014-3672 + * + * The QEMU shipped with Xen has a bodge. It checks for + * XEN_QEMU_CONSOLE_LIMIT to see how much data QEMU is allowed + * to write to stderr. We set that to 1MB if it is not set by + * system administrator. + */ +static void libxl__set_qemu_env_for_xsa_180(libxl__gc *gc, + flexarray_t *dm_envs) +{ + if (getenv("XEN_QEMU_CONSOLE_LIMIT")) return; + flexarray_append_pair(dm_envs, "XEN_QEMU_CONSOLE_LIMIT", "1048576"); +} + const libxl_vnc_info *libxl__dm_vnc(const libxl_domain_config *guest_config) { const libxl_vnc_info *vnc = NULL; @@ -1144,7 +1158,8 @@ void libxl__spawn_local_dm(libxl__egc *egc, libxl__dm_spawn_state *dmss) char *path, *logfile; int logfile_w, null; int rc; - char **args, **arg; + flexarray_t *dm_envs; + char **args, *const *envs, **arg; xs_transaction_t t; char *vm_path; char **pass_stuff; @@ -1171,6 +1186,10 @@ void libxl__spawn_local_dm(libxl__egc *egc, libxl__dm_spawn_state *dmss) goto out; } + dm_envs = flexarray_make(gc, 16, 1); + libxl__set_qemu_env_for_xsa_180(gc, dm_envs); + envs = (char**) flexarray_contents(dm_envs); + if (b_info->type == LIBXL_DOMAIN_TYPE_HVM) { path = xs_get_domain_path(ctx->xsh, domid); libxl__xs_write(gc, XBT_NULL, @@ -1248,7 +1267,7 @@ retry_transaction: goto out_close; if (!rc) { /* inner child */ setsid(); - libxl__exec(gc, null, logfile_w, logfile_w, dm, args, NULL); + libxl__exec(gc, null, logfile_w, logfile_w, dm, args, envs); } rc = 0;