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authorLinus Torvalds <torvalds@linux-foundation.org>2022-10-10 13:04:25 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-10-10 13:04:25 -0700
commit3604a7f568d3f67be8c13736201411ee83b210a1 (patch)
tree6eeed1b02493c7dc481318317215dbd2d72567f9 /drivers/char/hw_random/core.c
parentd4013bc4d49f6da8178a340348369bb9920225c9 (diff)
parentb411b1a0c8bddd470fc8c3457629ac25a168cba0 (diff)
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Merge tag 'v6.1-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu: "API: - Feed untrusted RNGs into /dev/random - Allow HWRNG sleeping to be more interruptible - Create lib/utils module - Setting private keys no longer required for akcipher - Remove tcrypt mode=1000 - Reorganised Kconfig entries Algorithms: - Load x86/sha512 based on CPU features - Add AES-NI/AVX/x86_64/GFNI assembler implementation of aria cipher Drivers: - Add HACE crypto driver aspeed" * tag 'v6.1-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (124 commits) crypto: aspeed - Remove redundant dev_err call crypto: scatterwalk - Remove unused inline function scatterwalk_aligned() crypto: aead - Remove unused inline functions from aead crypto: bcm - Simplify obtain the name for cipher crypto: marvell/octeontx - use sysfs_emit() to instead of scnprintf() hwrng: core - start hwrng kthread also for untrusted sources crypto: zip - remove the unneeded result variable crypto: qat - add limit to linked list parsing crypto: octeontx2 - Remove the unneeded result variable crypto: ccp - Remove the unneeded result variable crypto: aspeed - Fix check for platform_get_irq() errors crypto: virtio - fix memory-leak crypto: cavium - prevent integer overflow loading firmware crypto: marvell/octeontx - prevent integer overflows crypto: aspeed - fix build error when only CRYPTO_DEV_ASPEED is enabled crypto: hisilicon/qm - fix the qos value initialization crypto: sun4i-ss - use DEFINE_SHOW_ATTRIBUTE to simplify sun4i_ss_debugfs crypto: tcrypt - add async speed test for aria cipher crypto: aria-avx - add AES-NI/AVX/x86_64/GFNI assembler implementation of aria cipher crypto: aria - prepare generic module for optimized implementations ...
Diffstat (limited to 'drivers/char/hw_random/core.c')
-rw-r--r--drivers/char/hw_random/core.c55
1 files changed, 25 insertions, 30 deletions
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c
index 16f227b995e8..cc002b0c2f0c 100644
--- a/drivers/char/hw_random/core.c
+++ b/drivers/char/hw_random/core.c
@@ -52,7 +52,7 @@ MODULE_PARM_DESC(default_quality,
static void drop_current_rng(void);
static int hwrng_init(struct hwrng *rng);
-static void hwrng_manage_rngd(struct hwrng *rng);
+static int hwrng_fillfn(void *unused);
static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,
int wait);
@@ -96,6 +96,15 @@ static int set_current_rng(struct hwrng *rng)
drop_current_rng();
current_rng = rng;
+ /* if necessary, start hwrng thread */
+ if (!hwrng_fill) {
+ hwrng_fill = kthread_run(hwrng_fillfn, NULL, "hwrng");
+ if (IS_ERR(hwrng_fill)) {
+ pr_err("hwrng_fill thread creation failed\n");
+ hwrng_fill = NULL;
+ }
+ }
+
return 0;
}
@@ -167,8 +176,6 @@ skip_init:
rng->quality = 1024;
current_quality = rng->quality; /* obsolete */
- hwrng_manage_rngd(rng);
-
return 0;
}
@@ -454,10 +461,6 @@ static ssize_t rng_quality_store(struct device *dev,
/* the best available RNG may have changed */
ret = enable_best_rng();
- /* start/stop rngd if necessary */
- if (current_rng)
- hwrng_manage_rngd(current_rng);
-
out:
mutex_unlock(&rng_mutex);
return ret ? ret : len;
@@ -507,16 +510,14 @@ static int hwrng_fillfn(void *unused)
rng->quality = current_quality; /* obsolete */
quality = rng->quality;
mutex_unlock(&reading_mutex);
- put_rng(rng);
- if (!quality)
- break;
+ if (rc <= 0)
+ hwrng_msleep(rng, 10000);
- if (rc <= 0) {
- pr_warn("hwrng: no data available\n");
- msleep_interruptible(10000);
+ put_rng(rng);
+
+ if (rc <= 0)
continue;
- }
/* If we cannot credit at least one bit of entropy,
* keep track of the remainder for the next iteration
@@ -533,22 +534,6 @@ static int hwrng_fillfn(void *unused)
return 0;
}
-static void hwrng_manage_rngd(struct hwrng *rng)
-{
- if (WARN_ON(!mutex_is_locked(&rng_mutex)))
- return;
-
- if (rng->quality == 0 && hwrng_fill)
- kthread_stop(hwrng_fill);
- if (rng->quality > 0 && !hwrng_fill) {
- hwrng_fill = kthread_run(hwrng_fillfn, NULL, "hwrng");
- if (IS_ERR(hwrng_fill)) {
- pr_err("hwrng_fill thread creation failed\n");
- hwrng_fill = NULL;
- }
- }
-}
-
int hwrng_register(struct hwrng *rng)
{
int err = -EINVAL;
@@ -570,6 +555,7 @@ int hwrng_register(struct hwrng *rng)
init_completion(&rng->cleanup_done);
complete(&rng->cleanup_done);
+ init_completion(&rng->dying);
if (!current_rng ||
(!cur_rng_set_by_user && rng->quality > current_rng->quality)) {
@@ -617,6 +603,7 @@ void hwrng_unregister(struct hwrng *rng)
old_rng = current_rng;
list_del(&rng->list);
+ complete_all(&rng->dying);
if (current_rng == rng) {
err = enable_best_rng();
if (err) {
@@ -685,6 +672,14 @@ void devm_hwrng_unregister(struct device *dev, struct hwrng *rng)
}
EXPORT_SYMBOL_GPL(devm_hwrng_unregister);
+long hwrng_msleep(struct hwrng *rng, unsigned int msecs)
+{
+ unsigned long timeout = msecs_to_jiffies(msecs) + 1;
+
+ return wait_for_completion_interruptible_timeout(&rng->dying, timeout);
+}
+EXPORT_SYMBOL_GPL(hwrng_msleep);
+
static int __init hwrng_modinit(void)
{
int ret;