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authorLinus Torvalds <torvalds@linux-foundation.org>2024-01-10 23:23:43 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2024-01-10 23:23:43 +0300
commit0cb552aa97843f24549ce808883494138471c16b (patch)
tree805d1a4a46b68929c2ca2f878b58840e19dee550 /drivers/char/hw_random/core.c
parent6434eade5dd51f12b464c8dc16633f0f2d26e284 (diff)
parentb8910630c967ffee582289451ddb5f9f19c26872 (diff)
downloadlinux-0cb552aa97843f24549ce808883494138471c16b.tar.xz
Merge tag 'v6.8-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu: "API: - Add incremental lskcipher/skcipher processing Algorithms: - Remove SHA1 from drbg - Remove CFB and OFB Drivers: - Add comp high perf mode configuration in hisilicon/zip - Add support for 420xx devices in qat - Add IAA Compression Accelerator driver" * tag 'v6.8-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (172 commits) crypto: iaa - Account for cpu-less numa nodes crypto: scomp - fix req->dst buffer overflow crypto: sahara - add support for crypto_engine crypto: sahara - remove error message for bad aes request size crypto: sahara - remove unnecessary NULL assignments crypto: sahara - remove 'active' flag from sahara_aes_reqctx struct crypto: sahara - use dev_err_probe() crypto: sahara - use devm_clk_get_enabled() crypto: sahara - use BIT() macro crypto: sahara - clean up macro indentation crypto: sahara - do not resize req->src when doing hash operations crypto: sahara - fix processing hash requests with req->nbytes < sg->length crypto: sahara - improve error handling in sahara_sha_process() crypto: sahara - fix wait_for_completion_timeout() error handling crypto: sahara - fix ahash reqsize crypto: sahara - handle zero-length aes requests crypto: skcipher - remove excess kerneldoc members crypto: shash - remove excess kerneldoc members crypto: qat - generate dynamically arbiter mappings crypto: qat - add support for ring pair level telemetry ...
Diffstat (limited to 'drivers/char/hw_random/core.c')
-rw-r--r--drivers/char/hw_random/core.c34
1 files changed, 21 insertions, 13 deletions
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c
index 420f155d251f..a3bbdd6e60fc 100644
--- a/drivers/char/hw_random/core.c
+++ b/drivers/char/hw_random/core.c
@@ -23,10 +23,13 @@
#include <linux/sched.h>
#include <linux/sched/signal.h>
#include <linux/slab.h>
+#include <linux/string.h>
#include <linux/uaccess.h>
#define RNG_MODULE_NAME "hw_random"
+#define RNG_BUFFER_SIZE (SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES)
+
static struct hwrng *current_rng;
/* the current rng has been explicitly chosen by user via sysfs */
static int cur_rng_set_by_user;
@@ -58,7 +61,7 @@ static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,
static size_t rng_buffer_size(void)
{
- return SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES;
+ return RNG_BUFFER_SIZE;
}
static void add_early_randomness(struct hwrng *rng)
@@ -209,6 +212,7 @@ static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size,
static ssize_t rng_dev_read(struct file *filp, char __user *buf,
size_t size, loff_t *offp)
{
+ u8 buffer[RNG_BUFFER_SIZE];
ssize_t ret = 0;
int err = 0;
int bytes_read, len;
@@ -236,34 +240,37 @@ static ssize_t rng_dev_read(struct file *filp, char __user *buf,
if (bytes_read < 0) {
err = bytes_read;
goto out_unlock_reading;
+ } else if (bytes_read == 0 &&
+ (filp->f_flags & O_NONBLOCK)) {
+ err = -EAGAIN;
+ goto out_unlock_reading;
}
+
data_avail = bytes_read;
}
- if (!data_avail) {
- if (filp->f_flags & O_NONBLOCK) {
- err = -EAGAIN;
- goto out_unlock_reading;
- }
- } else {
- len = data_avail;
+ len = data_avail;
+ if (len) {
if (len > size)
len = size;
data_avail -= len;
- if (copy_to_user(buf + ret, rng_buffer + data_avail,
- len)) {
+ memcpy(buffer, rng_buffer + data_avail, len);
+ }
+ mutex_unlock(&reading_mutex);
+ put_rng(rng);
+
+ if (len) {
+ if (copy_to_user(buf + ret, buffer, len)) {
err = -EFAULT;
- goto out_unlock_reading;
+ goto out;
}
size -= len;
ret += len;
}
- mutex_unlock(&reading_mutex);
- put_rng(rng);
if (need_resched())
schedule_timeout_interruptible(1);
@@ -274,6 +281,7 @@ static ssize_t rng_dev_read(struct file *filp, char __user *buf,
}
}
out:
+ memzero_explicit(buffer, sizeof(buffer));
return ret ? : err;
out_unlock_reading: