diff options
| author | Jason A. Donenfeld <Jason@zx2c4.com> | 2022-03-01 20:03:49 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-06-22 14:11:13 +0200 |
| commit | 631503001ccf6ff08e816a2edecba0f9f939fab7 (patch) | |
| tree | 831f24030869b25c6c708714516eb222ad3941b5 /lib | |
| parent | 1ae73fb2a6351b6f864da010295237c4d87d834e (diff) | |
random: replace custom notifier chain with standard one
commit 5acd35487dc911541672b3ffc322851769c32a56 upstream.
We previously rolled our own randomness readiness notifier, which only
has two users in the whole kernel. Replace this with a more standard
atomic notifier block that serves the same purpose with less code. Also
unexport the symbols, because no modules use it, only unconditional
builtins. The only drawback is that it's possible for a notification
handler returning the "stop" code to prevent further processing, but
given that there are only two users, and that we're unexporting this
anyway, that doesn't seem like a significant drawback for the
simplification we receive here.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
[Jason: for stable, also backported to crypto/drbg.c, not unexporting.]
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/random32.c | 13 | ||||
| -rw-r--r-- | lib/vsprintf.c | 10 |
2 files changed, 14 insertions, 9 deletions
diff --git a/lib/random32.c b/lib/random32.c index 42cbb70e09d8..339624191b51 100644 --- a/lib/random32.c +++ b/lib/random32.c @@ -40,6 +40,7 @@ #include <linux/sched.h> #include <linux/bitops.h> #include <linux/slab.h> +#include <linux/notifier.h> #include <asm/unaligned.h> /** @@ -546,9 +547,11 @@ static void prandom_reseed(struct timer_list *unused) * To avoid worrying about whether it's safe to delay that interrupt * long enough to seed all CPUs, just schedule an immediate timer event. */ -static void prandom_timer_start(struct random_ready_callback *unused) +static int prandom_timer_start(struct notifier_block *nb, + unsigned long action, void *data) { mod_timer(&seed_timer, jiffies); + return 0; } /* @@ -557,13 +560,13 @@ static void prandom_timer_start(struct random_ready_callback *unused) */ static int __init prandom_init_late(void) { - static struct random_ready_callback random_ready = { - .func = prandom_timer_start + static struct notifier_block random_ready = { + .notifier_call = prandom_timer_start }; - int ret = add_random_ready_callback(&random_ready); + int ret = register_random_ready_notifier(&random_ready); if (ret == -EALREADY) { - prandom_timer_start(&random_ready); + prandom_timer_start(&random_ready, 0, NULL); ret = 0; } return ret; diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 2766d1b2c301..393623bf3258 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -731,14 +731,16 @@ static void enable_ptr_key_workfn(struct work_struct *work) static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn); -static void fill_random_ptr_key(struct random_ready_callback *unused) +static int fill_random_ptr_key(struct notifier_block *nb, + unsigned long action, void *data) { /* This may be in an interrupt handler. */ queue_work(system_unbound_wq, &enable_ptr_key_work); + return 0; } -static struct random_ready_callback random_ready = { - .func = fill_random_ptr_key +static struct notifier_block random_ready = { + .notifier_call = fill_random_ptr_key }; static int __init initialize_ptr_random(void) @@ -752,7 +754,7 @@ static int __init initialize_ptr_random(void) return 0; } - ret = add_random_ready_callback(&random_ready); + ret = register_random_ready_notifier(&random_ready); if (!ret) { return 0; } else if (ret == -EALREADY) { |