Change 3222717 by automation@vsergiienko-flipday-internal-rtd1395-nemo on 2022/11/02 14:06:37
commit 1a55116834aad9a6fe7d3ea03e4a6998150eb2fb
Author: Manjur Khan <mokhan@xxxxxxxx>
Date: Mon Oct 31 13:20:42 2022 -0700
REALTEK-9066 credit-rng to Nemo to fix FW-133531 by improving entropy at boot for WPA3 TLS OpenSSL+, patch-2 applied.
From git@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx:rtd1315x-stark/stark.git
From bf8a4000ed271b6772ec4562fa3309ed07bdaf0b
From: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
Date: Wed, 29 Dec 2021 22:10:03 +0100
Subject: [PATCH] random: fix crash on multiple early calls to
add_bootloader_randomness()
Currently, if CONFIG_RANDOM_TRUST_BOOTLOADER is enabled, multiple calls
to add_bootloader_randomness() are broken and can cause a NULL pointer
dereference, as noted by Ivan T. Ivanov. This is not only a hypothetical
problem, as qemu on arm64 may provide bootloader entropy via EFI and via
devicetree.
On the first call to add_hwgenerator_randomness(), crng_fast_load() is
executed, and if the seed is long enough, crng_init will be set to 1.
On subsequent calls to add_bootloader_randomness() and then to
add_hwgenerator_randomness(), crng_fast_load() will be skipped. Instead,
wait_event_interruptible() and then credit_entropy_bits() will be
called.
If the entropy count for that second seed is large enough, that proceeds
to crng_reseed().
However, both wait_event_interruptible() and crng_reseed() depends
(at least in numa_crng_init()) on workqueues. Therefore, test whether
system_wq is already initialized, which is a sufficient indicator that
workqueue_init_early() has progressed far enough.
If we wind up hitting the !system_wq case, we later want to do what
would have been done there when wqs are up, so set a flag, and do that
work later from the rand_initialize() call.
Reported-by: Ivan T. Ivanov <iivanov@xxxxxxx>
Fixes: 18b915ac6b0a ("efi/random: Treat EFI_RNG_PROTOCOL output as
bootloader randomness")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
[Jason: added crng_need_done state and related logic.]
Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx>
Affected files ...
.. //depot/firmware/release/main/port/realtek/rtd1395/platform/software_phoenix/linux-kernel/drivers/char/random.c#3 edit
Differences ...
==== //depot/firmware/release/main/port/realtek/rtd1395/platform/software_phoenix/linux-kernel/drivers/char/random.c#3 (text) ====
@@ -432,6 +432,7 @@
* its value (from 0->1->2).
*/
static int crng_init = 0;
+static bool crng_need_final_init = false;
#define crng_ready() (likely(crng_init > 1))
static int crng_init_cnt = 0;
static unsigned long crng_global_init_time = 0;
@@ -860,6 +861,36 @@
static void numa_crng_init(void) {}
#endif
+static void crng_finalize_init(struct crng_state *crng)
+{
+ if (crng != &primary_crng || crng_init >= 2)
+ return;
+ if (!system_wq) {
+ /* We can't call numa_crng_init until we have workqueues,
+ * so mark this for processing later. */
+ crng_need_final_init = true;
+ return;
+ }
+
+ numa_crng_init();
+ crng_init = 2;
+ process_random_ready_list();
+ wake_up_interruptible(&crng_init_wait);
+ pr_notice("random: crng init done\n");
+ if (unseeded_warning.missed) {
+ pr_notice("random: %d get_random_xx warning(s) missed "
+ "due to ratelimiting\n",
+ unseeded_warning.missed);
+ unseeded_warning.missed = 0;
+ }
+ if (urandom_warning.missed) {
+ pr_notice("random: %d urandom warning(s) missed "
+ "due to ratelimiting\n",
+ urandom_warning.missed);
+ urandom_warning.missed = 0;
+ }
+}
+
static void crng_reseed(struct crng_state *crng, struct entropy_store *r)
{
unsigned long flags;
@@ -888,25 +919,7 @@
}
memzero_explicit(&buf, sizeof(buf));
crng->init_time = jiffies;
- if (crng == &primary_crng && crng_init < 2) {
- numa_crng_init();
- crng_init = 2;
- process_random_ready_list();
- wake_up_interruptible(&crng_init_wait);
- pr_notice("random: crng init done\n");
- if (unseeded_warning.missed) {
- pr_notice("random: %d get_random_xx warning(s) missed "
- "due to ratelimiting\n",
- unseeded_warning.missed);
- unseeded_warning.missed = 0;
- }
- if (urandom_warning.missed) {
- pr_notice("random: %d urandom warning(s) missed "
- "due to ratelimiting\n",
- urandom_warning.missed);
- urandom_warning.missed = 0;
- }
- }
+ crng_finalize_init(crng);
spin_unlock_irqrestore(&crng->lock, flags);
}
@@ -1717,6 +1730,8 @@
{
init_std_data(&input_pool);
init_std_data(&blocking_pool);
+ if (crng_need_final_init)
+ crng_finalize_init(&primary_crng);
crng_initialize(&primary_crng);
crng_global_init_time = jiffies;
if (ratelimit_disable) {
@@ -2216,7 +2231,8 @@
* We'll be woken up again once below random_write_wakeup_thresh,
* or when the calling thread is about to terminate.
*/
- wait_event_interruptible(random_write_wait, kthread_should_stop() ||
+ wait_event_interruptible(random_write_wait,
+ !system_wq || kthread_should_stop() ||
ENTROPY_BITS(&input_pool) <= random_write_wakeup_bits);
mix_pool_bytes(poolp, buffer, count);
credit_entropy_bits(poolp, entropy);
