Patch "random: check for signals after page of pool writes" has been added to the 4.19-stable tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



This is a note to let you know that I've just added the patch titled

    random: check for signals after page of pool writes

to the 4.19-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     random-check-for-signals-after-page-of-pool-writes.patch
and it can be found in the queue-4.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From foo@baz Fri Jun 17 08:58:56 AM CEST 2022
From: "Jason A. Donenfeld" <Jason@xxxxxxxxx>
Date: Sun, 22 May 2022 22:25:41 +0200
Subject: random: check for signals after page of pool writes

From: "Jason A. Donenfeld" <Jason@xxxxxxxxx>

commit 1ce6c8d68f8ac587f54d0a271ac594d3d51f3efb upstream.

get_random_bytes_user() checks for signals after producing a PAGE_SIZE
worth of output, just like /dev/zero does. write_pool() is doing
basically the same work (actually, slightly more expensive), and so
should stop to check for signals in the same way. Let's also name it
write_pool_user() to match get_random_bytes_user(), so this won't be
misused in the future.

Before this patch, massive writes to /dev/urandom would tie up the
process for an extremely long time and make it unterminatable. After, it
can be successfully interrupted. The following test program can be used
to see this works as intended:

  #include <unistd.h>
  #include <fcntl.h>
  #include <signal.h>
  #include <stdio.h>

  static unsigned char x[~0U];

  static void handle(int) { }

  int main(int argc, char *argv[])
  {
    pid_t pid = getpid(), child;
    int fd;
    signal(SIGUSR1, handle);
    if (!(child = fork())) {
      for (;;)
        kill(pid, SIGUSR1);
    }
    fd = open("/dev/urandom", O_WRONLY);
    pause();
    printf("interrupted after writing %zd bytes\n", write(fd, x, sizeof(x)));
    close(fd);
    kill(child, SIGTERM);
    return 0;
  }

Result before: "interrupted after writing 2147479552 bytes"
Result after: "interrupted after writing 4096 bytes"

Cc: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/char/random.c |   14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1251,7 +1251,7 @@ static __poll_t random_poll(struct file
 	return crng_ready() ? EPOLLIN | EPOLLRDNORM : EPOLLOUT | EPOLLWRNORM;
 }
 
-static ssize_t write_pool(struct iov_iter *iter)
+static ssize_t write_pool_user(struct iov_iter *iter)
 {
 	u8 block[BLAKE2S_BLOCK_SIZE];
 	ssize_t ret = 0;
@@ -1266,7 +1266,13 @@ static ssize_t write_pool(struct iov_ite
 		mix_pool_bytes(block, copied);
 		if (!iov_iter_count(iter) || copied != sizeof(block))
 			break;
-		cond_resched();
+
+		BUILD_BUG_ON(PAGE_SIZE % sizeof(block) != 0);
+		if (ret % PAGE_SIZE == 0) {
+			if (signal_pending(current))
+				break;
+			cond_resched();
+		}
 	}
 
 	memzero_explicit(block, sizeof(block));
@@ -1275,7 +1281,7 @@ static ssize_t write_pool(struct iov_ite
 
 static ssize_t random_write_iter(struct kiocb *kiocb, struct iov_iter *iter)
 {
-	return write_pool(iter);
+	return write_pool_user(iter);
 }
 
 static ssize_t urandom_read_iter(struct kiocb *kiocb, struct iov_iter *iter)
@@ -1342,7 +1348,7 @@ static long random_ioctl(struct file *f,
 		ret = import_single_range(WRITE, p, len, &iov, &iter);
 		if (unlikely(ret))
 			return ret;
-		ret = write_pool(&iter);
+		ret = write_pool_user(&iter);
 		if (unlikely(ret < 0))
 			return ret;
 		/* Since we're crediting, enforce that it was all written into the pool. */


Patches currently in stable-queue which might be from Jason@xxxxxxxxx are

queue-4.19/random-do-not-take-pool-spinlock-at-boot.patch
queue-4.19/random-remove-kernel.random.read_wakeup_threshold.patch
queue-4.19/random-simplify-arithmetic-function-flow-in-account.patch
queue-4.19/random-order-timer-entropy-functions-below-interrupt-functions.patch
queue-4.19/random-introduce-drain_entropy-helper-to-declutter-crng_reseed.patch
queue-4.19/random-fix-locking-in-crng_fast_load.patch
queue-4.19/random-cleanup-uuid-handling.patch
queue-4.19/random-group-userspace-read-write-functions.patch
queue-4.19/random-make-credit_entropy_bits-always-safe.patch
queue-4.19/latent_entropy-avoid-build-error-when-plugin-cflags-are-not-set.patch
queue-4.19/revert-hwrng-core-freeze-khwrng-thread-during-suspend.patch
queue-4.19/drivers-char-random.c-make-primary_crng-static.patch
queue-4.19/random-do-not-re-init-if-crng_reseed-completes-before-primary-init.patch
queue-4.19/random-use-proper-jiffies-comparison-macro.patch
queue-4.19/init-call-time_init-before-rand_initialize.patch
queue-4.19/random-split-primary-secondary-crng-init-paths.patch
queue-4.19/random-pull-add_hwgenerator_randomness-declaration-into-random.h.patch
queue-4.19/random-unify-early-init-crng-load-accounting.patch
queue-4.19/drivers-char-random.c-remove-unused-stuct-poolinfo-poolbits.patch
queue-4.19/random-use-blake2s-instead-of-sha1-in-extraction.patch
queue-4.19/random-convert-to-using-fops-write_iter.patch
queue-4.19/random-initialize-chacha20-constants-with-correct-endianness.patch
queue-4.19/random-remove-incomplete-last_data-logic.patch
queue-4.19/random-group-entropy-extraction-functions.patch
queue-4.19/random-add-proper-spdx-header.patch
queue-4.19/linux-random.h-remove-arch_has_random-arch_has_random_seed.patch
queue-4.19/random-rewrite-header-introductory-comment.patch
queue-4.19/random-make-dev-random-be-almost-like-dev-urandom.patch
queue-4.19/random-remove-ifdef-d-out-interrupt-bench.patch
queue-4.19/um-use-fallback-for-random_get_entropy-instead-of-zero.patch
queue-4.19/lib-crypto-sha1-re-roll-loops-to-reduce-code-size.patch
queue-4.19/random-tie-batched-entropy-generation-to-base_crng-generation.patch
queue-4.19/sparc-use-fallback-for-random_get_entropy-instead-of-zero.patch
queue-4.19/random-use-linear-min-entropy-accumulation-crediting.patch
queue-4.19/random-remove-batched-entropy-locking.patch
queue-4.19/xtensa-use-fallback-for-random_get_entropy-instead-of-zero.patch
queue-4.19/powerpc-remove-arch_has_random-arch_has_random_seed.patch
queue-4.19/fdt-add-support-for-rng-seed.patch
queue-4.19/random-continually-use-hwgenerator-randomness.patch
queue-4.19/random-access-input_pool_data-directly-rather-than-through-pointer.patch
queue-4.19/random-add-arch_get_random_-long_early.patch
queue-4.19/random-inline-leaves-of-rand_initialize.patch
queue-4.19/random-cleanup-poolinfo-abstraction.patch
queue-4.19/random-wire-up-fops-splice_-read-write-_iter.patch
queue-4.19/random-handle-latent-entropy-and-command-line-from-random_init.patch
queue-4.19/random-remove-use_input_pool-parameter-from-crng_reseed.patch
queue-4.19/random-credit-architectural-init-the-exact-amount.patch
queue-4.19/ia64-define-get_cycles-macro-for-arch-override.patch
queue-4.19/random-replace-custom-notifier-chain-with-standard-one.patch
queue-4.19/random-support-freezable-kthreads-in-add_hwgenerator_randomness.patch
queue-4.19/random-document-get_random_int-family.patch
queue-4.19/random-remove-the-blocking-pool.patch
queue-4.19/random-avoid-initializing-twice-in-credit-race.patch
queue-4.19/random-avoid-warnings-for-config_numa-builds.patch
queue-4.19/crypto-drbg-add-fips-140-2-ctrng-for-noise-source.patch
queue-4.19/random-mark-bootloader-randomness-code-as-__init.patch
queue-4.19/random-zero-buffer-after-reading-entropy-from-userspace.patch
queue-4.19/random-remove-whitespace-and-reorder-includes.patch
queue-4.19/random-ignore-grnd_random-in-getentropy-2.patch
queue-4.19/random-clear-fast-pool-crng-and-batches-in-cpuhp-bring-up.patch
queue-4.19/random-document-add_hwgenerator_randomness-with-other-input-functions.patch
queue-4.19/random-fix-typo-in-add_timer_randomness.patch
queue-4.19/random-do-crng-pre-init-loading-in-worker-rather-than-irq.patch
queue-4.19/powerpc-use-bool-in-archrandom.h.patch
queue-4.19/random-do-not-split-fast-init-input-in-add_hwgenerator_randomness.patch
queue-4.19/timekeeping-add-raw-clock-fallback-for-random_get_entropy.patch
queue-4.19/random-early-initialization-of-chacha-constants.patch
queue-4.19/crypto-drbg-prepare-for-more-fine-grained-tracking-of-seeding-state.patch
queue-4.19/random-delete-code-to-pull-data-into-pools.patch
queue-4.19/crypto-drbg-always-try-to-free-jitter-rng-instance.patch
queue-4.19/random-simplify-entropy-debiting.patch
queue-4.19/random-don-t-reset-crng_init_cnt-on-urandom_read.patch
queue-4.19/random-skip-fast_init-if-hwrng-provides-large-chunk-of-entropy.patch
queue-4.19/random-use-siphash-as-interrupt-entropy-accumulator.patch
queue-4.19/random-avoid-checking-crng_ready-twice-in-random_init.patch
queue-4.19/random-fix-soft-lockup-when-trying-to-read-from-an-uninitialized-blocking-pool.patch
queue-4.19/random-group-sysctl-functions.patch
queue-4.19/random-don-t-let-644-read-only-sysctls-be-written-to.patch
queue-4.19/random-document-crng_fast_key_erasure-destination-possibility.patch
queue-4.19/random-only-wake-up-writers-after-zap-if-threshold-was-passed.patch
queue-4.19/random-use-wait_event_freezable-in-add_hwgenerator_randomness.patch
queue-4.19/random-check-for-signal-and-try-earlier-when-generating-entropy.patch
queue-4.19/random-check-for-signals-every-page_size-chunk-of-dev-random.patch
queue-4.19/arm-use-fallback-for-random_get_entropy-instead-of-zero.patch
queue-4.19/random-absorb-fast-pool-into-input-pool-after-fast-load.patch
queue-4.19/random-give-sysctl_random_min_urandom_seed-a-more-sensible-value.patch
queue-4.19/crypto-blake2s-generic-c-library-implementation-and-selftest.patch
queue-4.19/random-cleanup-fractional-entropy-shift-constants.patch
queue-4.19/random-use-rdseed-instead-of-rdrand-in-entropy-extraction.patch
queue-4.19/random-move-rand_initialize-earlier.patch
queue-4.19/random-don-t-wake-crng_init_wait-when-crng_init-1.patch
queue-4.19/random-add-a-urandom_read_nowait-for-random-apis-that-don-t-warn.patch
queue-4.19/random-do-not-sign-extend-bytes-for-rotation-when-mixing.patch
queue-4.19/random-move-initialization-functions-out-of-hot-pages.patch
queue-4.19/random-remove-dead-code-left-over-from-blocking-pool.patch
queue-4.19/drivers-char-random.c-constify-poolinfo_table.patch
queue-4.19/crypto-drbg-track-whether-drbg-was-seeded-with-rng_is_initialized.patch
queue-4.19/random-use-computational-hash-for-entropy-extraction.patch
queue-4.19/random-add-and-use-pr_fmt.patch
queue-4.19/random-round-robin-registers-as-ulong-not-u32.patch
queue-4.19/random-always-wake-up-entropy-writers-after-extraction.patch
queue-4.19/s390-remove-arch_has_random-arch_has_random_seed.patch
queue-4.19/random-do-not-xor-rdrand-when-writing-into-dev-random.patch
queue-4.19/crypto-drbg-make-reseeding-from-get_random_bytes-synchronous.patch
queue-4.19/random-convert-to-entropy_bits-for-better-code-readability.patch
queue-4.19/char-random-add-a-newline-at-the-end-of-the-file.patch
queue-4.19/random-move-randomize_page-into-mm-where-it-belongs.patch
queue-4.19/random-only-call-crng_finalize_init-for-primary_crng.patch
queue-4.19/random-cleanup-integer-types.patch
queue-4.19/random-re-add-removed-comment-about-get_random_-u32-u64-reseeding.patch
queue-4.19/random-unify-cycles_t-and-jiffies-usage-and-types.patch
queue-4.19/random-insist-on-random_get_entropy-existing-in-order-to-simplify.patch
queue-4.19/random-group-initialization-wait-functions.patch
queue-4.19/linux-random.h-mark-config_arch_random-functions-__must_check.patch
queue-4.19/random-remove-unused-extract_entropy-reserved-argument.patch
queue-4.19/random-check-for-signal_pending-outside-of-need_resched-check.patch
queue-4.19/random-access-primary_pool-directly-rather-than-through-pointer.patch
queue-4.19/random-fix-sysctl-documentation-nits.patch
queue-4.19/random-remove-unused-tracepoints.patch
queue-4.19/random-only-read-from-dev-random-after-its-pool-has-received-128-bits.patch
queue-4.19/nios2-use-fallback-for-random_get_entropy-instead-of-zero.patch
queue-4.19/random-treat-bootloader-trust-toggle-the-same-way-as-cpu-trust-toggle.patch
queue-4.19/random-make-consistent-usage-of-crng_ready.patch
queue-4.19/lib-crypto-blake2s-move-hmac-construction-into-wireguard.patch
queue-4.19/parisc-define-get_cycles-macro-for-arch-override.patch
queue-4.19/x86-tsc-use-fallback-for-random_get_entropy-instead-of-zero.patch
queue-4.19/random-add-grnd_insecure-to-return-best-effort-non-cryptographic-bytes.patch
queue-4.19/crypto-drbg-move-dynamic-reseed_threshold-adjustments-to-__drbg_seed.patch
queue-4.19/random-check-for-signals-after-page-of-pool-writes.patch
queue-4.19/random-make-random_get_entropy-return-an-unsigned-long.patch
queue-4.19/random-check-for-crng_init-0-in-add_device_randomness.patch
queue-4.19/random-remove-unnecessary-unlikely.patch
queue-4.19/random-defer-fast-pool-mixing-to-worker.patch
queue-4.19/random-harmonize-crng-init-done-messages.patch
queue-4.19/crypto-blake2s-include-linux-bug.h-instead-of-asm-bug.h.patch
queue-4.19/random-use-static-branch-for-crng_ready.patch
queue-4.19/random-rather-than-entropy_store-abstraction-use-global.patch
queue-4.19/random-remove-extern-from-functions-in-header.patch
queue-4.19/siphash-use-one-source-of-truth-for-siphash-permutations.patch
queue-4.19/random-group-entropy-collection-functions.patch
queue-4.19/random-de-duplicate-input_pool-constants.patch
queue-4.19/random-mix-build-time-latent-entropy-into-pool-at-init.patch
queue-4.19/random-remove-useless-header-comment.patch
queue-4.19/linux-random.h-use-false-with-bool.patch
queue-4.19/maintainers-co-maintain-random.c.patch
queue-4.19/random-remove-outdated-int_max-6-check-in-urandom_read.patch
queue-4.19/m68k-use-fallback-for-random_get_entropy-instead-of-zero.patch
queue-4.19/alpha-define-get_cycles-macro-for-arch-override.patch
queue-4.19/random-mix-bootloader-randomness-into-pool.patch
queue-4.19/random-remove-some-dead-code-of-poolinfo.patch
queue-4.19/random-do-not-use-batches-when-crng_ready.patch
queue-4.19/crypto-drbg-always-seeded-with-sp800-90b-compliant-noise-source.patch
queue-4.19/s390-define-get_cycles-macro-for-arch-override.patch
queue-4.19/random-do-not-pretend-to-handle-premature-next-security-model.patch
queue-4.19/random-avoid-arch_get_random_seed_long-when-collecting-irq-randomness.patch
queue-4.19/random-use-is_enabled-config_numa-instead-of-ifdefs.patch
queue-4.19/random-avoid-superfluous-call-to-rdrand-in-crng-extraction.patch
queue-4.19/random-use-symbolic-constants-for-crng_init-states.patch
queue-4.19/random-reseed-more-often-immediately-after-booting.patch
queue-4.19/random-ensure-early-rdseed-goes-through-mixer-on-init.patch
queue-4.19/random-deobfuscate-irq-u32-u64-contributions.patch
queue-4.19/random-do-not-use-input-pool-from-hard-irqs.patch
queue-4.19/random-help-compiler-out-with-fast_mix-by-using-simpler-arguments.patch
queue-4.19/revert-random-use-static-branch-for-crng_ready.patch
queue-4.19/random-fix-crash-on-multiple-early-calls-to-add_bootloader_randomness.patch
queue-4.19/random-account-for-arch-randomness-in-bits.patch
queue-4.19/crypto-blake2s-adjust-include-guard-naming.patch
queue-4.19/random-do-not-allow-user-to-keep-crng-key-around-on-stack.patch
queue-4.19/x86-remove-arch_has_random-arch_has_random_seed.patch
queue-4.19/random-remove-ratelimiting-for-in-kernel-unseeded-randomness.patch
queue-4.19/random-remove-unused-irq_flags-argument-from-add_interrupt_randomness.patch
queue-4.19/random-prepend-remaining-pool-constants-with-pool_.patch
queue-4.19/powerpc-define-get_cycles-macro-for-arch-override.patch
queue-4.19/random-remove-unused-output_pool-constants.patch
queue-4.19/mips-use-fallback-for-random_get_entropy-instead-of-just-c0-random.patch
queue-4.19/random-use-hash-function-for-crng_slow_load.patch
queue-4.19/random-fix-typo-in-comments.patch
queue-4.19/random-use-proper-return-types-on-get_random_-int-long-_wait.patch



[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux