weston/libweston/content-protection.c
Marius Vlad f722dc6f08 compositor: Prevent an invalid access against content protection
Avoids an user-after-free when destroying the surface, like in the
following ASAN message:

==25180==ERROR: AddressSanitizer: heap-use-after-free on address 0x6060000589d8 at pc 0x7ff70a4f7102 bp 0x7fff8f7e13b0 sp 0x7fff8f7e13a8
READ of size 8 at 0x6060000589d8 thread T0
    #0 0x7ff70a4f7101 in weston_schedule_surface_protection_update ../libweston/compositor.c:1163
    #1 0x7ff70a4f743b in weston_surface_update_output_mask ../libweston/compositor.c:1212
    #2 0x7ff70a4f7a47 in weston_surface_assign_output ../libweston/compositor.c:1298
    #3 0x7ff70a4f7f44 in weston_view_assign_output ../libweston/compositor.c:1348
    #4 0x7ff70a4fa12f in weston_view_update_transform ../libweston/compositor.c:1589
    #5 0x7ff70a4ffc20 in view_list_add ../libweston/compositor.c:2657
    #6 0x7ff70a5000ee in weston_compositor_build_view_list ../libweston/compositor.c:2688
    #7 0x7ff70a4fd577 in weston_view_destroy ../libweston/compositor.c:2202
    #8 0x7ff70a4fd7df in weston_surface_destroy ../libweston/compositor.c:2239
    #9 0x7ff70a4fdbb0 in destroy_surface ../libweston/compositor.c:2285
    #10 0x7ff70a4a2d3e in destroy_resource ../src/wayland-server.c:723
    #11 0x7ff70a4a8940 in for_each_helper ../src/wayland-util.c:372
    #12 0x7ff70a4a8e1f in wl_map_for_each ../src/wayland-util.c:385
    #13 0x7ff70a4a3748 in wl_client_destroy ../src/wayland-server.c:882
    #14 0x7ff6fe04e866 in shell_destroy ../desktop-shell/shell.c:5004
    #15 0x7ff70a4ee923 in wl_signal_emit /home/mvlad/install-amd64/include/wayland-server-core.h:481
    #16 0x7ff70a51598d in weston_compositor_destroy ../libweston/compositor.c:7903
    #17 0x7ff70a903a58 in wet_main ../compositor/main.c:3493
    #18 0x560de7b3b179 in main ../compositor/executable.c:33
    #19 0x7ff70a73ecc9 in __libc_start_main ../csu/libc-start.c:308
    #20 0x560de7b3b099 in _start (/home/mvlad/install-amd64/bin/weston+0x1099)

0x6060000589d8 is located 56 bytes inside of 64-byte region [0x6060000589a0,0x6060000589e0)
freed by thread T0 here:
    #0 0x7ff70a9d3b6f in __interceptor_free (/usr/lib/x86_64-linux-gnu/libasan.so.6+0xa9b6f)
    #1 0x7ff70a5167d2 in cp_destroy_listener ../libweston/content-protection.c:193
    #2 0x7ff70a4ee923 in wl_signal_emit /home/mvlad/install-amd64/include/wayland-server-core.h:481
    #3 0x7ff70a51598d in weston_compositor_destroy ../libweston/compositor.c:7903
    #4 0x7ff70a903a58 in wet_main ../compositor/main.c:3493
    #5 0x560de7b3b179 in main ../compositor/executable.c:33
    #6 0x7ff70a73ecc9 in __libc_start_main ../csu/libc-start.c:308

previously allocated by thread T0 here:
    #0 0x7ff70a9d4037 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.6+0xaa037)
    #1 0x7ff70a5160aa in zalloc ../include/libweston/zalloc.h:38
    #2 0x7ff70a516cda in weston_compositor_enable_content_protection ../libweston/content-protection.c:329
    #3 0x7ff7070247e0 in drm_backend_create ../libweston/backend-drm/drm.c:3180
    #4 0x7ff707024cae in weston_backend_init ../libweston/backend-drm/drm.c:3250
    #5 0x7ff70a515d02 in weston_compositor_load_backend ../libweston/compositor.c:7999
    #6 0x7ff70a8fbcfb in load_drm_backend ../compositor/main.c:2614
    #7 0x7ff70a900b46 in load_backend ../compositor/main.c:3103
    #8 0x7ff70a902ecd in wet_main ../compositor/main.c:3380
    #9 0x560de7b3b179 in main ../compositor/executable.c:33
    #10 0x7ff70a73ecc9 in __libc_start_main ../csu/libc-start.c:308

SUMMARY: AddressSanitizer: heap-use-after-free ../libweston/compositor.c:1163 in weston_schedule_surface_protection_update

Signed-off-by: Marius Vlad <marius.vlad@collabora.com>
2021-05-12 17:51:49 +03:00

349 lines
11 KiB
C

/*
* Copyright © 2019 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial
* portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include "config.h"
#include <stdint.h>
#include <stdlib.h>
#include <assert.h>
#include <signal.h>
#include <unistd.h>
#include <string.h>
#include <libweston/libweston.h>
#include <libweston/weston-log.h>
#include "libweston-internal.h"
#include "weston-content-protection-server-protocol.h"
#include "shared/helpers.h"
#include "shared/timespec-util.h"
#define content_protection_log(cp, ...) \
weston_log_scope_printf((cp)->debug, __VA_ARGS__)
static const char * const content_type_name [] = {
[WESTON_PROTECTED_SURFACE_TYPE_UNPROTECTED] = "UNPROTECTED",
[WESTON_PROTECTED_SURFACE_TYPE_HDCP_0] = "TYPE-0",
[WESTON_PROTECTED_SURFACE_TYPE_HDCP_1] = "TYPE-1",
};
void
weston_protected_surface_send_event(struct protected_surface *psurface,
enum weston_hdcp_protection protection)
{
struct wl_resource *p_resource;
enum weston_protected_surface_type protection_type;
struct content_protection *cp;
struct wl_resource *surface_resource;
p_resource = psurface->protection_resource;
if (!p_resource)
return;
/* No event to be sent to client, in case of enforced mode */
if (psurface->surface->protection_mode == WESTON_SURFACE_PROTECTION_MODE_ENFORCED)
return;
protection_type = (enum weston_protected_surface_type) protection;
weston_protected_surface_send_status(p_resource, protection_type);
cp = psurface->cp_backptr;
surface_resource = psurface->surface->resource;
content_protection_log(cp, "wl_surface@%"PRIu32" Protection type set to %s\n",
wl_resource_get_id(surface_resource),
content_type_name[protection_type]);
}
static void
set_type(struct wl_client *client, struct wl_resource *resource,
enum weston_protected_surface_type content_type)
{
struct content_protection *cp;
struct protected_surface *psurface;
enum weston_hdcp_protection weston_cp;
struct wl_resource *surface_resource;
psurface = wl_resource_get_user_data(resource);
if (!psurface)
return;
cp = psurface->cp_backptr;
surface_resource = psurface->surface->resource;
if (content_type < WESTON_PROTECTED_SURFACE_TYPE_UNPROTECTED ||
content_type > WESTON_PROTECTED_SURFACE_TYPE_HDCP_1) {
wl_resource_post_error(resource,
WESTON_PROTECTED_SURFACE_ERROR_INVALID_TYPE,
"wl_surface@%"PRIu32" Invalid content-type %d for request:set_type\n",
wl_resource_get_id(surface_resource), content_type);
content_protection_log(cp, "wl_surface@%"PRIu32" Invalid content-type %d for request:set_type\n",
wl_resource_get_id(surface_resource), content_type);
return;
}
content_protection_log(cp, "wl_surface@%"PRIu32" Request: Enable Content-Protection Type: %s\n",
wl_resource_get_id(surface_resource),
content_type_name[content_type]);
weston_cp = (enum weston_hdcp_protection) content_type;
psurface->surface->pending.desired_protection = weston_cp;
}
static void
protected_surface_destroy(struct wl_client *client, struct wl_resource *resource)
{
struct protected_surface *psurface;
psurface = wl_resource_get_user_data(resource);
if (!psurface)
return;
psurface->surface->pending.desired_protection = WESTON_HDCP_DISABLE;
}
static void
set_enforce_mode(struct wl_client *client, struct wl_resource *resource)
{
/*
* Enforce Censored-Visibility. Compositor censors the protected
* surface on an unsecured output.
* In case of a surface, being shown on an unprotected output, the
* compositor hides the surface, not allowing it to be displayed on
* the unprotected output, without bothering the client. No difference
* for the protected outputs.
*
* The member 'protection_mode' is "double-buffered", so setting it in
* pending_state will cause the setting of the corresponding
* 'protection_mode' in weston_surface, after the commit.
*
* This function sets the 'protection_mode' of the weston_surface_state
* to 'enfoced'. The renderers inspect the flag and compare the
* desired_protection of the surface, to the current_protection of the
* output, based on that the real surface or a place-holder content,
* (e.g. solid color) are shown.
*/
struct protected_surface *psurface;
psurface = wl_resource_get_user_data(resource);
if (!psurface)
return;
psurface->surface->pending.protection_mode =
WESTON_SURFACE_PROTECTION_MODE_ENFORCED;
}
static void
set_relax_mode(struct wl_client *client, struct wl_resource *resource)
{
/*
* Relaxed mode. By default this mode will be activated.
* In case of a surface, being shown in unprotected output,
* compositor just sends the event for protection status changed.
*
* On setting the relaxed mode, the 'protection_mode' member is queued
* to be set to 'relax' from the existing 'enforce' mode.
*/
struct protected_surface *psurface;
psurface = wl_resource_get_user_data(resource);
if (!psurface)
return;
psurface->surface->pending.protection_mode =
WESTON_SURFACE_PROTECTION_MODE_RELAXED;
}
static const struct weston_protected_surface_interface protected_surface_implementation = {
protected_surface_destroy,
set_type,
set_enforce_mode,
set_relax_mode,
};
static void
cp_destroy_listener(struct wl_listener *listener, void *data)
{
struct content_protection *cp;
cp = container_of(listener, struct content_protection,
destroy_listener);
wl_list_remove(&cp->destroy_listener.link);
wl_list_remove(&cp->protected_list);
weston_log_scope_destroy(cp->debug);
cp->debug = NULL;
cp->surface_protection_update = NULL;
cp->compositor->content_protection = NULL;
free(cp);
}
static void
free_protected_surface(struct protected_surface *psurface)
{
psurface->surface->pending.desired_protection = WESTON_HDCP_DISABLE;
wl_resource_set_user_data(psurface->protection_resource, NULL);
wl_list_remove(&psurface->surface_destroy_listener.link);
wl_list_remove(&psurface->link);
free(psurface);
}
static void
surface_destroyed(struct wl_listener *listener, void *data)
{
struct protected_surface *psurface;
psurface = container_of(listener, struct protected_surface,
surface_destroy_listener);
free_protected_surface(psurface);
}
static void
destroy_protected_surface(struct wl_resource *resource)
{
struct protected_surface *psurface;
psurface = wl_resource_get_user_data(resource);
if (!psurface)
return;
free_protected_surface(psurface);
}
static void
get_protection(struct wl_client *client, struct wl_resource *cp_resource,
uint32_t id, struct wl_resource *surface_resource)
{
struct wl_resource *resource;
struct weston_surface *surface;
struct content_protection *cp;
struct protected_surface *psurface;
struct wl_listener *listener;
surface = wl_resource_get_user_data(surface_resource);
assert(surface);
cp = wl_resource_get_user_data(cp_resource);
assert(cp);
/*
* Check if this client has a corresponding protected-surface
*/
listener = wl_resource_get_destroy_listener(surface->resource,
surface_destroyed);
if (listener) {
wl_resource_post_error(cp_resource,
WESTON_CONTENT_PROTECTION_ERROR_SURFACE_EXISTS,
"wl_surface@%"PRIu32" Protection already exists",
wl_resource_get_id(surface_resource));
return;
}
psurface = zalloc(sizeof(struct protected_surface));
if (!psurface) {
wl_client_post_no_memory(client);
return;
}
psurface->cp_backptr = cp;
resource = wl_resource_create(client, &weston_protected_surface_interface,
1, id);
if (!resource) {
free(psurface);
wl_client_post_no_memory(client);
return;
}
wl_list_insert(&cp->protected_list, &psurface->link);
wl_resource_set_implementation(resource, &protected_surface_implementation,
psurface,
destroy_protected_surface);
psurface->protection_resource = resource;
psurface->surface = surface;
psurface->surface_destroy_listener.notify = surface_destroyed;
wl_resource_add_destroy_listener(surface->resource,
&psurface->surface_destroy_listener);
weston_protected_surface_send_event(psurface,
psurface->surface->current_protection);
}
static void
destroy_protection(struct wl_client *client, struct wl_resource *cp_resource)
{
wl_resource_destroy(cp_resource);
}
static const
struct weston_content_protection_interface content_protection_implementation = {
destroy_protection,
get_protection,
};
static void
bind_weston_content_protection(struct wl_client *client, void *data,
uint32_t version, uint32_t id)
{
struct content_protection *cp = data;
struct wl_resource *resource;
resource = wl_resource_create(client,
&weston_content_protection_interface,
1, id);
if (!resource) {
wl_client_post_no_memory(client);
return;
}
wl_resource_set_implementation(resource,
&content_protection_implementation,
cp, NULL);
}
/* Advertise the content-protection support.
*
* Calling this function sets up the content-protection support via HDCP.
* This exposes the global interface, visible to the client, enabling them to
* request for content-protection for their surfaces according to the type of
* content.
*/
WL_EXPORT int
weston_compositor_enable_content_protection(struct weston_compositor *compositor)
{
struct content_protection *cp;
cp = zalloc(sizeof(*cp));
if (cp == NULL)
return -1;
cp->compositor = compositor;
compositor->content_protection = cp;
wl_list_init(&cp->protected_list);
if (wl_global_create(compositor->wl_display,
&weston_content_protection_interface, 1, cp,
bind_weston_content_protection) == NULL)
return -1;
cp->destroy_listener.notify = cp_destroy_listener;
wl_signal_add(&compositor->destroy_signal, &cp->destroy_listener);
cp->debug = weston_compositor_add_log_scope(compositor, "content-protection-debug",
"debug-logs for content-protection",
NULL, NULL, NULL);
return 0;
}