mirrors/wlroots
1
0
Fork 0
mirror of https://gitlab.freedesktop.org/wlroots/wlroots.git synced 2025-11-03 09:01:40 -05:00
Code Issues Projects Releases Packages Wiki Activity Actions

output: fix leak of empty back buffer lock

Browse source 
This refactors output_ensure_buffer() to not mutate the state passed,
making the previous subtle behavior much more explicit.

Fixes: d483dd2f ("output: add wlr_output_commit_state")
Closes: #3442
This commit is contained in:
Isaac Freund 2022-06-03 00:15:42 +02:00 • committed by Simon Ser
parent 5cca72958a
commit 0deef6fe44
3 changed files with 77 additions and 34 deletions
Download patch file Download diff file Expand all files Collapse all files

2
include/types/wlr_output.h
View file

@ -13,6 +13,6 @@ struct wlr_drm_format *output_pick_format(struct wlr_output *output,
const struct wlr_drm_format_set *display_formats, uint32_t format);
void output_clear_back_buffer(struct wlr_output *output);
bool output_ensure_buffer(struct wlr_output *output,
struct wlr_output_state *state);
const struct wlr_output_state *state, bool *new_back_buffer);
#endif

51
types/output/output.c
View file

@ -677,22 +677,29 @@ static bool output_basic_test(struct wlr_output *output,
bool wlr_output_test_state(struct wlr_output *output,
const struct wlr_output_state *state) {
bool had_buffer = state->committed & WLR_OUTPUT_STATE_BUFFER;
// Duplicate the state because we might mutate it in output_ensure_buffer
struct wlr_output_state pending = *state;
if (!output_basic_test(output, &pending)) {
return false;
}
if (!output_ensure_buffer(output, &pending)) {
if (!output_basic_test(output, state)) {
return false;
}
if (!output->impl->test) {
return true;
}
bool success = output->impl->test(output, &pending);
if (!had_buffer) {
bool new_back_buffer = false;
if (!output_ensure_buffer(output, state, &new_back_buffer)) {
return false;
}
// Create a shallow copy of the state with the new buffer
// potentially included to pass to the backend.
struct wlr_output_state copy = *state;
if (new_back_buffer) {
assert((copy.committed & WLR_OUTPUT_STATE_BUFFER) == 0);
copy.committed |= WLR_OUTPUT_STATE_BUFFER;
copy.buffer = output->back_buffer;
}
bool success = output->impl->test(output, &copy);
if (new_back_buffer) {
output_clear_back_buffer(output);
}
return success;
@ -710,13 +717,23 @@ bool wlr_output_commit_state(struct wlr_output *output,
return false;
}
// Duplicate the state because we might mutate it in output_ensure_buffer
struct wlr_output_state pending = *state;
if (!output_ensure_buffer(output, &pending)) {
bool new_back_buffer = false;
if (!output_ensure_buffer(output, state, &new_back_buffer)) {
output_clear_back_buffer(output);
return false;
}
// Create a shallow copy of the state with the new back buffer
// potentially included to pass to the backend.
struct wlr_output_state pending = *state;
if (new_back_buffer) {
assert((pending.committed & WLR_OUTPUT_STATE_BUFFER) == 0);
pending.committed |= WLR_OUTPUT_STATE_BUFFER;
// Lock the buffer to ensure it stays valid past the
// output_clear_back_buffer() call below.
pending.buffer = wlr_buffer_lock(output->back_buffer);
}
if ((pending.committed & WLR_OUTPUT_STATE_BUFFER) &&
output->idle_frame != NULL) {
wl_event_source_remove(output->idle_frame);
@ -746,6 +763,9 @@ bool wlr_output_commit_state(struct wlr_output *output,
if (!output->impl->commit(output, &pending)) {
wlr_buffer_unlock(back_buffer);
if (new_back_buffer) {
wlr_buffer_unlock(pending.buffer);
}
return false;
}
@ -820,8 +840,9 @@ bool wlr_output_commit_state(struct wlr_output *output,
};
wlr_signal_emit_safe(&output->events.commit, &event);
if (back_buffer != NULL) {
wlr_buffer_unlock(back_buffer);
wlr_buffer_unlock(back_buffer);
if (new_back_buffer) {
wlr_buffer_unlock(pending.buffer);
}
return true;

58
types/output/render.c
View file

@ -99,7 +99,7 @@ static bool output_create_swapchain(struct wlr_output *output,
}
static bool output_attach_back_buffer(struct wlr_output *output,
struct wlr_output_state *state, int *buffer_age) {
const struct wlr_output_state *state, int *buffer_age) {
assert(output->back_buffer == NULL);
if (!output_create_swapchain(output, state, true)) {
@ -151,11 +151,11 @@ bool wlr_output_attach_render(struct wlr_output *output, int *buffer_age) {
return output_attach_render(output, &output->pending, buffer_age);
}
static bool output_attach_empty_buffer(struct wlr_output *output,
struct wlr_output_state *state) {
static bool output_attach_empty_back_buffer(struct wlr_output *output,
const struct wlr_output_state *state) {
assert(!(state->committed & WLR_OUTPUT_STATE_BUFFER));
if (!output_attach_render(output, state, NULL)) {
if (!output_attach_back_buffer(output, state, NULL)) {
return false;
}
@ -170,8 +170,28 @@ static bool output_attach_empty_buffer(struct wlr_output *output,
return true;
}
static bool output_test_with_back_buffer(struct wlr_output *output,
const struct wlr_output_state *state) {
assert(output->impl->test != NULL);
// Create a shallow copy of the state with the empty back buffer included
// to pass to the backend.
struct wlr_output_state copy = *state;
assert((copy.committed & WLR_OUTPUT_STATE_BUFFER) == 0);
copy.committed |= WLR_OUTPUT_STATE_BUFFER;
assert(output->back_buffer != NULL);
copy.buffer = output->back_buffer;
return output->impl->test(output, &copy);
}
// This function may attach a new, empty back buffer if necessary.
// If so, the new_back_buffer out parameter will be set to true.
bool output_ensure_buffer(struct wlr_output *output,
struct wlr_output_state *state) {
const struct wlr_output_state *state,
bool *new_back_buffer) {
assert(*new_back_buffer == false);
// If we're lighting up an output or changing its mode, make sure to
// provide a new buffer
bool needs_new_buffer = false;
@ -196,15 +216,16 @@ bool output_ensure_buffer(struct wlr_output *output,
wlr_log(WLR_DEBUG, "Attaching empty buffer to output for modeset");
if (!output_attach_empty_buffer(output, state)) {
goto error;
if (!output_attach_empty_back_buffer(output, state)) {
return false;
}
if (!output->impl->test || output->impl->test(output, state)) {
if (output_test_with_back_buffer(output, state)) {
*new_back_buffer = true;
return true;
}
output_clear_back_buffer(output);
state->committed &= ~WLR_OUTPUT_STATE_BUFFER;
if (output->swapchain->format->len == 0) {
return false;
@ -217,17 +238,18 @@ bool output_ensure_buffer(struct wlr_output *output,
if (!output_create_swapchain(output, state, false)) {
return false;
}
if (!output_attach_empty_buffer(output, state)) {
goto error;
}
if (!output->impl->test(output, state)) {
goto error;
}
return true;
error:
if (!output_attach_empty_back_buffer(output, state)) {
return false;
}
if (output_test_with_back_buffer(output, state)) {
*new_back_buffer = true;
return true;
}
output_clear_back_buffer(output);
state->committed &= ~WLR_OUTPUT_STATE_BUFFER;
return false;
}