workaround for audio service sorting bug

RP1A.200720.011.2020.10.01.23
Daniel Micay 2020-05-28 20:19:14 -04:00
parent 39bdab1671
commit 2c7cbd9c17
1 changed files with 12 additions and 3 deletions

View File

@ -79,6 +79,7 @@ static union {
bool zero_on_free;
bool purge_slabs;
bool region_quarantine_protect;
bool slot_randomize;
};
char padding[PAGE_SIZE];
} ro __attribute__((aligned(PAGE_SIZE)));
@ -350,7 +351,7 @@ static u64 get_mask(size_t slots) {
}
static size_t get_free_slot(struct random_state *rng, size_t slots, struct slab_metadata *metadata) {
if (SLOT_RANDOMIZE) {
if (ro.slot_randomize) {
// randomize start location for linear search (uniform random choice is too slow)
unsigned random_index = get_random_u16_uniform(rng, slots);
unsigned first_bitmap = random_index / 64;
@ -1055,17 +1056,24 @@ static inline void enforce_init(void) {
}
}
COLD static void handle_hal_bugs(void) {
COLD static void handle_bugs(void) {
char path[256];
if (readlink("/proc/self/exe", path, sizeof(path)) == -1) {
return;
}
const char camera_provider[] = "/vendor/bin/hw/android.hardware.camera.provider@2.4-service_64";
if (strcmp(camera_provider, path) == 0) {
ro.zero_on_free = false;
ro.purge_slabs = false;
ro.region_quarantine_protect = false;
}
// DeviceDescriptor sorting wrongly relies on malloc addresses
const char audio_service[] = "/system/bin/audioserver";
if (strcmp(audio_service, path) == 0) {
ro.slot_randomize = false;
}
}
COLD static void init_slow_path(void) {
@ -1085,7 +1093,8 @@ COLD static void init_slow_path(void) {
ro.purge_slabs = true;
ro.zero_on_free = ZERO_ON_FREE;
ro.region_quarantine_protect = true;
handle_hal_bugs();
ro.slot_randomize = SLOT_RANDOMIZE;
handle_bugs();
if (sysconf(_SC_PAGESIZE) != PAGE_SIZE) {
fatal_error("runtime page size does not match compile-time page size which is not supported");