diff options
Diffstat (limited to 'drivers/char/hw_random/core.c')
| -rw-r--r-- | drivers/char/hw_random/core.c | 38 |
1 files changed, 20 insertions, 18 deletions
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index 4084df65c9fa..96d7fe41b373 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -161,7 +161,6 @@ static int hwrng_init(struct hwrng *rng) reinit_completion(&rng->cleanup_done); skip_init: - rng->quality = min_t(u16, min_t(u16, default_quality, 1024), rng->quality ?: 1024); current_quality = rng->quality; /* obsolete */ return 0; @@ -182,8 +181,15 @@ static inline int rng_get_data(struct hwrng *rng, u8 *buffer, size_t size, int present; BUG_ON(!mutex_is_locked(&reading_mutex)); - if (rng->read) - return rng->read(rng, (void *)buffer, size, wait); + if (rng->read) { + int err; + + err = rng->read(rng, buffer, size, wait); + if (WARN_ON_ONCE(err > 0 && err > size)) + err = size; + + return err; + } if (rng->data_present) present = rng->data_present(rng, wait); @@ -335,6 +341,9 @@ static ssize_t rng_current_store(struct device *dev, if (sysfs_streq(buf, "")) { err = enable_best_rng(); + } else if (sysfs_streq(buf, "none")) { + cur_rng_set_by_user = 1; + drop_current_rng(); } else { list_for_each_entry(rng, &rng_list, list) { if (sysfs_streq(rng->name, buf)) { @@ -386,7 +395,7 @@ static ssize_t rng_available_show(struct device *dev, strlcat(buf, rng->name, PAGE_SIZE); strlcat(buf, " ", PAGE_SIZE); } - strlcat(buf, "\n", PAGE_SIZE); + strlcat(buf, "none\n", PAGE_SIZE); mutex_unlock(&rng_mutex); return strlen(buf); @@ -470,16 +479,6 @@ static struct attribute *rng_dev_attrs[] = { ATTRIBUTE_GROUPS(rng_dev); -static void __exit unregister_miscdev(void) -{ - misc_deregister(&rng_miscdev); -} - -static int __init register_miscdev(void) -{ - return misc_register(&rng_miscdev); -} - static int hwrng_fillfn(void *unused) { size_t entropy, entropy_credit = 0; /* in 1/1024 of a bit */ @@ -545,8 +544,11 @@ int hwrng_register(struct hwrng *rng) complete(&rng->cleanup_done); init_completion(&rng->dying); - if (!current_rng || - (!cur_rng_set_by_user && rng->quality > current_rng->quality)) { + /* Adjust quality field to always have a proper value */ + rng->quality = min3(default_quality, 1024, rng->quality ?: 1024); + + if (!cur_rng_set_by_user && + (!current_rng || rng->quality > current_rng->quality)) { /* * Set new rng as current as the new rng source * provides better entropy quality and was not @@ -668,7 +670,7 @@ static int __init hwrng_modinit(void) return -ENOMEM; } - ret = register_miscdev(); + ret = misc_register(&rng_miscdev); if (ret) { kfree(rng_fillbuf); kfree(rng_buffer); @@ -685,7 +687,7 @@ static void __exit hwrng_modexit(void) kfree(rng_fillbuf); mutex_unlock(&rng_mutex); - unregister_miscdev(); + misc_deregister(&rng_miscdev); } fs_initcall(hwrng_modinit); /* depends on misc_register() */ |