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-rw-r--r--NEWS4
-rw-r--r--include/stdlib.h12
-rw-r--r--malloc/thread-freeres.c2
-rw-r--r--nptl/allocatestack.c3
-rw-r--r--stdlib/Makefile2
-rw-r--r--stdlib/Versions5
-rw-r--r--stdlib/arc4random.c208
-rw-r--r--stdlib/arc4random.h48
-rw-r--r--stdlib/arc4random_uniform.c140
-rw-r--r--stdlib/chacha20.c187
-rw-r--r--stdlib/stdlib.h13
-rw-r--r--sysdeps/generic/not-cancel.h2
-rw-r--r--sysdeps/generic/tls-internal-struct.h1
-rw-r--r--sysdeps/generic/tls-internal.c18
-rw-r--r--sysdeps/generic/tls-internal.h7
-rw-r--r--sysdeps/mach/hurd/_Fork.c2
-rw-r--r--sysdeps/mach/hurd/i386/libc.abilist3
-rw-r--r--sysdeps/mach/hurd/not-cancel.h3
-rw-r--r--sysdeps/nptl/_Fork.c2
-rw-r--r--sysdeps/unix/sysv/linux/aarch64/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/alpha/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/arc/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/arm/be/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/arm/le/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/csky/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/hppa/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/i386/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/ia64/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/microblaze/be/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/microblaze/le/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/nios2/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/not-cancel.h7
-rw-r--r--sysdeps/unix/sysv/linux/or1k/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/sh/be/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/sh/le/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/tls-internal.c39
-rw-r--r--sysdeps/unix/sysv/linux/tls-internal.h8
-rw-r--r--sysdeps/unix/sysv/linux/x86_64/64/libc.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist3
55 files changed, 800 insertions, 15 deletions
diff --git a/NEWS b/NEWS
index df882ec243..8420a65cd0 100644
--- a/NEWS
+++ b/NEWS
@@ -60,6 +60,10 @@ Major new features:
   _GNU_SOURCE macro is defined and the C++20 __cpp_char8_t feature test macro
   is not defined (if __cpp_char8_t is defined, then char8_t is a builtin type).
 
+* The functions arc4random, arc4random_buf, and arc4random_uniform have been
+  added.  The functions use a pseudo-random number generator along with
+  entropy from the kernel.
+
 Deprecated and removed features, and other changes affecting compatibility:
 
 * Support for prelink will be removed in the next release; this includes
diff --git a/include/stdlib.h b/include/stdlib.h
index 1c6f70b082..cae7f7cdf8 100644
--- a/include/stdlib.h
+++ b/include/stdlib.h
@@ -144,6 +144,18 @@ libc_hidden_proto (__ptsname_r)
 libc_hidden_proto (grantpt)
 libc_hidden_proto (unlockpt)
 
+__typeof (arc4random) __arc4random;
+libc_hidden_proto (__arc4random);
+__typeof (arc4random_buf) __arc4random_buf;
+libc_hidden_proto (__arc4random_buf);
+__typeof (arc4random_uniform) __arc4random_uniform;
+libc_hidden_proto (__arc4random_uniform);
+extern void __arc4random_buf_internal (void *buffer, size_t len)
+     attribute_hidden;
+/* Called from the fork function to reinitialize the internal cipher state
+   in child process.  */
+extern void __arc4random_fork_subprocess (void) attribute_hidden;
+
 extern double __strtod_internal (const char *__restrict __nptr,
 				 char **__restrict __endptr, int __group)
      __THROW __nonnull ((1)) __wur;
diff --git a/malloc/thread-freeres.c b/malloc/thread-freeres.c
index 3894652169..b22e1d789f 100644
--- a/malloc/thread-freeres.c
+++ b/malloc/thread-freeres.c
@@ -36,7 +36,7 @@ __libc_thread_freeres (void)
   __rpc_thread_destroy ();
 #endif
   call_function_static_weak (__res_thread_freeres);
-  __glibc_tls_internal_free ();
+  call_function_static_weak (__glibc_tls_internal_free);
   call_function_static_weak (__libc_dlerror_result_free);
 
   /* This should come last because it shuts down malloc for this
diff --git a/nptl/allocatestack.c b/nptl/allocatestack.c
index 98f5f6dd85..219854f2cb 100644
--- a/nptl/allocatestack.c
+++ b/nptl/allocatestack.c
@@ -32,6 +32,7 @@
 #include <kernel-features.h>
 #include <nptl-stack.h>
 #include <libc-lock.h>
+#include <tls-internal.h>
 
 /* Default alignment of stack.  */
 #ifndef STACK_ALIGN
@@ -127,7 +128,7 @@ get_cached_stack (size_t *sizep, void **memp)
 
   result->exiting = false;
   __libc_lock_init (result->exit_lock);
-  result->tls_state = (struct tls_internal_t) { 0 };
+  memset (&result->tls_state, 0, sizeof result->tls_state);
 
   /* Clear the DTV.  */
   dtv_t *dtv = GET_DTV (TLS_TPADJ (result));
diff --git a/stdlib/Makefile b/stdlib/Makefile
index d4a4d5679a..62f8253225 100644
--- a/stdlib/Makefile
+++ b/stdlib/Makefile
@@ -53,6 +53,8 @@ routines := \
   a64l \
   abort \
   abs \
+  arc4random \
+  arc4random_uniform \
   at_quick_exit \
   atof \
   atoi \
diff --git a/stdlib/Versions b/stdlib/Versions
index 5e9099a153..d09a308fb5 100644
--- a/stdlib/Versions
+++ b/stdlib/Versions
@@ -136,6 +136,11 @@ libc {
     strtof32; strtof64; strtof32x;
     strtof32_l; strtof64_l; strtof32x_l;
   }
+  GLIBC_2.36 {
+    arc4random;
+    arc4random_buf;
+    arc4random_uniform;
+  }
   GLIBC_PRIVATE {
     # functions which have an additional interface since they are
     # are cancelable.
diff --git a/stdlib/arc4random.c b/stdlib/arc4random.c
new file mode 100644
index 0000000000..65547e79aa
--- /dev/null
+++ b/stdlib/arc4random.c
@@ -0,0 +1,208 @@
+/* Pseudo Random Number Generator based on ChaCha20.
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <arc4random.h>
+#include <errno.h>
+#include <not-cancel.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <sys/param.h>
+#include <sys/random.h>
+#include <tls-internal.h>
+
+/* arc4random keeps two counters: 'have' is the current valid bytes not yet
+   consumed in 'buf' while 'count' is the maximum number of bytes until a
+   reseed.
+
+   Both the initial seed and reseed try to obtain entropy from the kernel
+   and abort the process if none could be obtained.
+
+   The state 'buf' improves the usage of the cipher calls, allowing to call
+   optimized implementations (if the architecture provides it) and minimize
+   function call overhead.  */
+
+#include <chacha20.c>
+
+/* Called from the fork function to reset the state.  */
+void
+__arc4random_fork_subprocess (void)
+{
+  struct arc4random_state_t *state = __glibc_tls_internal ()->rand_state;
+  if (state != NULL)
+    {
+      explicit_bzero (state, sizeof (*state));
+      /* Force key init.  */
+      state->count = -1;
+    }
+}
+
+/* Return the current thread random state or try to create one if there is
+   none available.  In the case malloc can not allocate a state, arc4random
+   will try to get entropy with arc4random_getentropy.  */
+static struct arc4random_state_t *
+arc4random_get_state (void)
+{
+  struct arc4random_state_t *state = __glibc_tls_internal ()->rand_state;
+  if (state == NULL)
+    {
+      state = malloc (sizeof (struct arc4random_state_t));
+      if (state != NULL)
+	{
+	  /* Force key initialization on first call.  */
+	  state->count = -1;
+	  __glibc_tls_internal ()->rand_state = state;
+	}
+    }
+  return state;
+}
+
+static void
+arc4random_getrandom_failure (void)
+{
+  __libc_fatal ("Fatal glibc error: cannot get entropy for arc4random\n");
+}
+
+static void
+arc4random_rekey (struct arc4random_state_t *state, uint8_t *rnd, size_t rndlen)
+{
+  chacha20_crypt (state->ctx, state->buf, state->buf, sizeof state->buf);
+
+  /* Mix optional user provided data.  */
+  if (rnd != NULL)
+    {
+      size_t m = MIN (rndlen, CHACHA20_KEY_SIZE + CHACHA20_IV_SIZE);
+      for (size_t i = 0; i < m; i++)
+	state->buf[i] ^= rnd[i];
+    }
+
+  /* Immediately reinit for backtracking resistance.  */
+  chacha20_init (state->ctx, state->buf, state->buf + CHACHA20_KEY_SIZE);
+  explicit_bzero (state->buf, CHACHA20_KEY_SIZE + CHACHA20_IV_SIZE);
+  state->have = sizeof (state->buf) - (CHACHA20_KEY_SIZE + CHACHA20_IV_SIZE);
+}
+
+static void
+arc4random_getentropy (void *rnd, size_t len)
+{
+  if (__getrandom_nocancel (rnd, len, GRND_NONBLOCK) == len)
+    return;
+
+  int fd = TEMP_FAILURE_RETRY (__open64_nocancel ("/dev/urandom",
+						  O_RDONLY | O_CLOEXEC));
+  if (fd != -1)
+    {
+      uint8_t *p = rnd;
+      uint8_t *end = p + len;
+      do
+	{
+	  ssize_t ret = TEMP_FAILURE_RETRY (__read_nocancel (fd, p, end - p));
+	  if (ret <= 0)
+	    arc4random_getrandom_failure ();
+	  p += ret;
+	}
+      while (p < end);
+
+      if (__close_nocancel (fd) == 0)
+	return;
+    }
+  arc4random_getrandom_failure ();
+}
+
+/* Check if the thread context STATE should be reseed with kernel entropy
+   depending of requested LEN bytes.  If there is less than requested,
+   the state is either initialized or reseeded, otherwise the internal
+   counter subtract the requested length.  */
+static void
+arc4random_check_stir (struct arc4random_state_t *state, size_t len)
+{
+  if (state->count <= len || state->count == -1)
+    {
+      uint8_t rnd[CHACHA20_KEY_SIZE + CHACHA20_IV_SIZE];
+      arc4random_getentropy (rnd, sizeof rnd);
+
+      if (state->count == -1)
+	chacha20_init (state->ctx, rnd, rnd + CHACHA20_KEY_SIZE);
+      else
+	arc4random_rekey (state, rnd, sizeof rnd);
+
+      explicit_bzero (rnd, sizeof rnd);
+
+      /* Invalidate the buf.  */
+      state->have = 0;
+      memset (state->buf, 0, sizeof state->buf);
+      state->count = CHACHA20_RESEED_SIZE;
+    }
+  else
+    state->count -= len;
+}
+
+void
+__arc4random_buf (void *buffer, size_t len)
+{
+  struct arc4random_state_t *state = arc4random_get_state ();
+  if (__glibc_unlikely (state == NULL))
+    {
+      arc4random_getentropy (buffer, len);
+      return;
+    }
+
+  arc4random_check_stir (state, len);
+  while (len > 0)
+    {
+      if (state->have > 0)
+	{
+	  size_t m = MIN (len, state->have);
+	  uint8_t *ks = state->buf + sizeof (state->buf) - state->have;
+	  memcpy (buffer, ks, m);
+	  explicit_bzero (ks, m);
+	  buffer += m;
+	  len -= m;
+	  state->have -= m;
+	}
+      if (state->have == 0)
+	arc4random_rekey (state, NULL, 0);
+    }
+}
+libc_hidden_def (__arc4random_buf)
+weak_alias (__arc4random_buf, arc4random_buf)
+
+uint32_t
+__arc4random (void)
+{
+  uint32_t r;
+
+  struct arc4random_state_t *state = arc4random_get_state ();
+  if (__glibc_unlikely (state == NULL))
+    {
+      arc4random_getentropy (&r, sizeof (uint32_t));
+      return r;
+    }
+
+  arc4random_check_stir (state, sizeof (uint32_t));
+  if (state->have < sizeof (uint32_t))
+    arc4random_rekey (state, NULL, 0);
+  uint8_t *ks = state->buf + sizeof (state->buf) - state->have;
+  memcpy (&r, ks, sizeof (uint32_t));
+  memset (ks, 0, sizeof (uint32_t));
+  state->have -= sizeof (uint32_t);
+
+  return r;
+}
+libc_hidden_def (__arc4random)
+weak_alias (__arc4random, arc4random)
diff --git a/stdlib/arc4random.h b/stdlib/arc4random.h
new file mode 100644
index 0000000000..cd39389c19
--- /dev/null
+++ b/stdlib/arc4random.h
@@ -0,0 +1,48 @@
+/* Arc4random definition used on TLS.
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _CHACHA20_H
+#define _CHACHA20_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+/* Internal ChaCha20 state.  */
+#define CHACHA20_STATE_LEN	16
+#define CHACHA20_BLOCK_SIZE	64
+
+/* Maximum number bytes until reseed (16 MB).  */
+#define CHACHA20_RESEED_SIZE	(16 * 1024 * 1024)
+
+/* Internal arc4random buffer, used on each feedback step so offer some
+   backtracking protection and to allow better used of vectorized
+   chacha20 implementations.  */
+#define CHACHA20_BUFSIZE        (8 * CHACHA20_BLOCK_SIZE)
+
+_Static_assert (CHACHA20_BUFSIZE >= CHACHA20_BLOCK_SIZE + CHACHA20_BLOCK_SIZE,
+		"CHACHA20_BUFSIZE < CHACHA20_BLOCK_SIZE + CHACHA20_BLOCK_SIZE");
+
+struct arc4random_state_t
+{
+  uint32_t ctx[CHACHA20_STATE_LEN];
+  size_t have;
+  size_t count;
+  uint8_t buf[CHACHA20_BUFSIZE];
+};
+
+#endif
diff --git a/stdlib/arc4random_uniform.c b/stdlib/arc4random_uniform.c
new file mode 100644
index 0000000000..1326dfa593
--- /dev/null
+++ b/stdlib/arc4random_uniform.c
@@ -0,0 +1,140 @@
+/* Random pseudo generator number which returns a single 32 bit value
+   uniformly distributed but with an upper_bound.
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <endian.h>
+#include <libc-lock.h>
+#include <stdlib.h>
+#include <sys/param.h>
+
+/* Return the number of bytes which cover values up to the limit.  */
+__attribute__ ((const))
+static uint32_t
+byte_count (uint32_t n)
+{
+  if (n < (1U << 8))
+    return 1;
+  else if (n < (1U << 16))
+    return 2;
+  else if (n < (1U << 24))
+    return 3;
+  else
+    return 4;
+}
+
+/* Fill the lower bits of the result with randomness, according to the
+   number of bytes requested.  */
+static void
+random_bytes (uint32_t *result, uint32_t byte_count)
+{
+  *result = 0;
+  unsigned char *ptr = (unsigned char *) result;
+  if (__BYTE_ORDER == __BIG_ENDIAN)
+    ptr += 4 - byte_count;
+  __arc4random_buf (ptr, byte_count);
+}
+
+uint32_t
+__arc4random_uniform (uint32_t n)
+{
+  if (n <= 1)
+    /* There is no valid return value for a zero limit, and 0 is the
+       only possible result for limit 1.  */
+    return 0;
+
+  /* The bits variable serves as a source for bits.  Prefetch the
+     minimum number of bytes needed.  */
+  uint32_t count = byte_count (n);
+  uint32_t bits_length = count * CHAR_BIT;
+  uint32_t bits;
+  random_bytes (&bits, count);
+
+  /* Powers of two are easy.  */
+  if (powerof2 (n))
+    return bits & (n - 1);
+
+  /* The general case.  This algorithm follows Jérémie Lumbroso,
+     Optimal Discrete Uniform Generation from Coin Flips, and
+     Applications (2013), who credits Donald E. Knuth and Andrew
+     C. Yao, The complexity of nonuniform random number generation
+     (1976), for solving the general case.
+
+     The implementation below unrolls the initialization stage of the
+     loop, where v is less than n.  */
+
+  /* Use 64-bit variables even though the intermediate results are
+     never larger than 33 bits.  This ensures the code is easier to
+     compile on 64-bit architectures.  */
+  uint64_t v;
+  uint64_t c;
+
+  /* Initialize v and c.  v is the smallest power of 2 which is larger
+     than n.*/
+  {
+    uint32_t log2p1 = 32 - __builtin_clz (n);
+    v = 1ULL << log2p1;
+    c = bits & (v - 1);
+    bits >>= log2p1;
+    bits_length -= log2p1;
+  }
+
+  /* At the start of the loop, c is uniformly distributed within the
+     half-open interval [0, v), and v < 2n < 2**33.  */
+  while (true)
+    {
+      if (v >= n)
+        {
+          /* If the candidate is less than n, accept it.  */
+          if (c < n)
+            /* c is uniformly distributed on [0, n).  */
+            return c;
+          else
+            {
+              /* c is uniformly distributed on [n, v).  */
+              v -= n;
+              c -= n;
+              /* The distribution was shifted, so c is uniformly
+                 distributed on [0, v) again.  */
+            }
+        }
+      /* v < n here.  */
+
+      /* Replenish the bit source if necessary.  */
+      if (bits_length == 0)
+        {
+          /* Overwrite the least significant byte.  */
+	  random_bytes (&bits, 1);
+	  bits_length = CHAR_BIT;
+        }
+
+      /* Double the range.  No overflow because v < n < 2**32.  */
+      v *= 2;
+      /* v < 2n here.  */
+
+      /* Extract a bit and append it to c.  c remains less than v and
+         thus 2**33.  */
+      c = (c << 1) | (bits & 1);
+      bits >>= 1;
+      --bits_length;
+
+      /* At this point, c is uniformly distributed on [0, v) again,
+         and v < 2n < 2**33.  */
+    }
+}
+libc_hidden_def (__arc4random_uniform)
+weak_alias (__arc4random_uniform, arc4random_uniform)
diff --git a/stdlib/chacha20.c b/stdlib/chacha20.c
new file mode 100644
index 0000000000..c47b8418f2
--- /dev/null
+++ b/stdlib/chacha20.c
@@ -0,0 +1,187 @@
+/* Generic ChaCha20 implementation (used on arc4random).
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <array_length.h>
+#include <endian.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+/* 32-bit stream position, then 96-bit nonce.  */
+#define CHACHA20_IV_SIZE	16
+#define CHACHA20_KEY_SIZE	32
+
+#define CHACHA20_STATE_LEN	16
+
+/* The ChaCha20 implementation is based on RFC8439 [1], omitting the final
+   XOR of the keystream with the plaintext because the plaintext is a
+   stream of zeros.  */
+
+enum chacha20_constants
+{
+  CHACHA20_CONSTANT_EXPA = 0x61707865U,
+  CHACHA20_CONSTANT_ND_3 = 0x3320646eU,
+  CHACHA20_CONSTANT_2_BY = 0x79622d32U,
+  CHACHA20_CONSTANT_TE_K = 0x6b206574U
+};
+
+static inline uint32_t
+read_unaligned_32 (const uint8_t *p)
+{
+  uint32_t r;
+  memcpy (&r, p, sizeof (r));
+  return r;
+}
+
+static inline void
+write_unaligned_32 (uint8_t *p, uint32_t v)
+{
+  memcpy (p, &v, sizeof (v));
+}
+
+#if __BYTE_ORDER == __BIG_ENDIAN
+# define read_unaligned_le32(p) __builtin_bswap32 (read_unaligned_32 (p))
+# define set_state(v)		__builtin_bswap32 ((v))
+#else
+# define read_unaligned_le32(p) read_unaligned_32 ((p))
+# define set_state(v)		(v)
+#endif
+
+static inline void
+chacha20_init (uint32_t *state, const uint8_t *key, const uint8_t *iv)
+{
+  state[0]  = CHACHA20_CONSTANT_EXPA;
+  state[1]  = CHACHA20_CONSTANT_ND_3;
+  state[2]  = CHACHA20_CONSTANT_2_BY;
+  state[3]  = CHACHA20_CONSTANT_TE_K;
+
+  state[4]  = read_unaligned_le32 (key + 0 * sizeof (uint32_t));
+  state[5]  = read_unaligned_le32 (key + 1 * sizeof (uint32_t));
+  state[6]  = read_unaligned_le32 (key + 2 * sizeof (uint32_t));
+  state[7]  = read_unaligned_le32 (key + 3 * sizeof (uint32_t));
+  state[8]  = read_unaligned_le32 (key + 4 * sizeof (uint32_t));
+  state[9]  = read_unaligned_le32 (key + 5 * sizeof (uint32_t));
+  state[10] = read_unaligned_le32 (key + 6 * sizeof (uint32_t));
+  state[11] = read_unaligned_le32 (key + 7 * sizeof (uint32_t));
+
+  state[12] = read_unaligned_le32 (iv + 0 * sizeof (uint32_t));
+  state[13] = read_unaligned_le32 (iv + 1 * sizeof (uint32_t));
+  state[14] = read_unaligned_le32 (iv + 2 * sizeof (uint32_t));
+  state[15] = read_unaligned_le32 (iv + 3 * sizeof (uint32_t));
+}
+
+static inline uint32_t
+rotl32 (unsigned int shift, uint32_t word)
+{
+  return (word << (shift & 31)) | (word >> ((-shift) & 31));
+}
+
+static void
+state_final (const uint8_t *src, uint8_t *dst, uint32_t v)
+{
+#ifdef CHACHA20_XOR_FINAL
+  v ^= read_unaligned_32 (src);
+#endif
+  write_unaligned_32 (dst, v);
+}
+
+static inline void
+chacha20_block (uint32_t *state, uint8_t *dst, const uint8_t *src)
+{
+  uint32_t x0, x1, x2, x3, x4, x5, x6, x7;
+  uint32_t x8, x9, x10, x11, x12, x13, x14, x15;
+
+  x0 = state[0];
+  x1 = state[1];
+  x2 = state[2];
+  x3 = state[3];
+  x4 = state[4];
+  x5 = state[5];
+  x6 = state[6];
+  x7 = state[7];
+  x8 = state[8];
+  x9 = state[9];
+  x10 = state[10];
+  x11 = state[11];
+  x12 = state[12];
+  x13 = state[13];
+  x14 = state[14];
+  x15 = state[15];
+
+  for (int i = 0; i < 20; i += 2)
+    {
+#define QROUND(_x0, _x1, _x2, _x3) 			\
+  do {							\
+   _x0 = _x0 + _x1; _x3 = rotl32 (16, (_x0 ^ _x3)); 	\
+   _x2 = _x2 + _x3; _x1 = rotl32 (12, (_x1 ^ _x2)); 	\
+   _x0 = _x0 + _x1; _x3 = rotl32 (8,  (_x0 ^ _x3));	\
+   _x2 = _x2 + _x3; _x1 = rotl32 (7,  (_x1 ^ _x2));	\
+  } while(0)
+
+      QROUND (x0, x4, x8,  x12);
+      QROUND (x1, x5, x9,  x13);
+      QROUND (x2, x6, x10, x14);
+      QROUND (x3, x7, x11, x15);
+
+      QROUND (x0, x5, x10, x15);
+      QROUND (x1, x6, x11, x12);
+      QROUND (x2, x7, x8,  x13);
+      QROUND (x3, x4, x9,  x14);
+    }
+
+  state_final (&src[0], &dst[0], set_state (x0 + state[0]));
+  state_final (&src[4], &dst[4], set_state (x1 + state[1]));
+  state_final (&src[8], &dst[8], set_state (x2 + state[2]));
+  state_final (&src[12], &dst[12], set_state (x3 + state[3]));
+  state_final (&src[16], &dst[16], set_state (x4 + state[4]));
+  state_final (&src[20], &dst[20], set_state (x5 + state[5]));
+  state_final (&src[24], &dst[24], set_state (x6 + state[6]));
+  state_final (&src[28], &dst[28], set_state (x7 + state[7]));
+  state_final (&src[32], &dst[32], set_state (x8 + state[8]));
+  state_final (&src[36], &dst[36], set_state (x9 + state[9]));
+  state_final (&src[40], &dst[40], set_state (x10 + state[10]));
+  state_final (&src[44], &dst[44], set_state (x11 + state[11]));
+  state_final (&src[48], &dst[48], set_state (x12 + state[12]));
+  state_final (&src[52], &dst[52], set_state (x13 + state[13]));
+  state_final (&src[56], &dst[56], set_state (x14 + state[14]));
+  state_final (&src[60], &dst[60], set_state (x15 + state[15]));
+
+  state[12]++;
+}
+
+static void
+chacha20_crypt (uint32_t *state, uint8_t *dst, const uint8_t *src,
+		size_t bytes)
+{
+  while (bytes >= CHACHA20_BLOCK_SIZE)
+    {
+      chacha20_block (state, dst, src);
+
+      bytes -= CHACHA20_BLOCK_SIZE;
+      dst += CHACHA20_BLOCK_SIZE;
+      src += CHACHA20_BLOCK_SIZE;
+    }
+
+  if (__glibc_unlikely (bytes != 0))
+    {
+      uint8_t stream[CHACHA20_BLOCK_SIZE];
+      chacha20_block (state, stream, src);
+      memcpy (dst, stream, bytes);
+      explicit_bzero (stream, sizeof stream);
+    }
+}
diff --git a/stdlib/stdlib.h b/stdlib/stdlib.h
index bf7cd438e1..3a630a0ce8 100644
--- a/stdlib/stdlib.h
+++ b/stdlib/stdlib.h
@@ -533,6 +533,19 @@ extern int seed48_r (unsigned short int __seed16v[3],
 extern int lcong48_r (unsigned short int __param[7],
 		      struct drand48_data *__buffer)
      __THROW __nonnull ((1, 2));
+
+/* Return a random integer between zero and 2**32-1 (inclusive).  */
+extern __uint32_t arc4random (void)
+     __THROW __wur;
+
+/* Fill the buffer with random data.  */
+extern void arc4random_buf (void *__buf, size_t __size)
+     __THROW __nonnull ((1));
+
+/* Return a random number between zero (inclusive) and the specified
+   limit (exclusive).  */
+extern __uint32_t arc4random_uniform (__uint32_t __upper_bound)
+     __THROW __wur;
 # endif	/* Use misc.  */
 #endif	/* Use misc or X/Open.  */
 
diff --git a/sysdeps/generic/not-cancel.h b/sysdeps/generic/not-cancel.h
index 2104efeb54..acceb9b67f 100644
--- a/sysdeps/generic/not-cancel.h
+++ b/sysdeps/generic/not-cancel.h
@@ -48,5 +48,7 @@
   (void) __writev (fd, iov, n)
 #define __fcntl64_nocancel(fd, cmd, ...) \
   __fcntl64 (fd, cmd, __VA_ARGS__)
+#define __getrandom_nocancel(buf, size, flags) \
+  __getrandom (buf, size, flags)
 
 #endif /* NOT_CANCEL_H  */
diff --git a/sysdeps/generic/tls-internal-struct.h b/sysdeps/generic/tls-internal-struct.h
index d76c715a96..a91915831b 100644
--- a/sysdeps/generic/tls-internal-struct.h
+++ b/sysdeps/generic/tls-internal-struct.h
@@ -23,6 +23,7 @@ struct tls_internal_t
 {
   char *strsignal_buf;
   char *strerror_l_buf;
+  struct arc4random_state_t *rand_state;
 };
 
 #endif
diff --git a/sysdeps/generic/tls-internal.c b/sysdeps/generic/tls-internal.c
index 898c20b61c..8a0f37d509 100644
--- a/sysdeps/generic/tls-internal.c
+++ b/sysdeps/generic/tls-internal.c
@@ -16,6 +16,24 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
+#include <stdlib/arc4random.h>
+#include <string.h>
 #include <tls-internal.h>
 
 __thread struct tls_internal_t __tls_internal;
+
+void
+__glibc_tls_internal_free (void)
+{
+  free (__tls_internal.strsignal_buf);
+  free (__tls_internal.strerror_l_buf);
+
+  if (__tls_internal.rand_state != NULL)
+    {
+      /* Clear any lingering random state prior so if the thread stack is
+	 cached it won't leak any data.  */
+      explicit_bzero (__tls_internal.rand_state,
+		      sizeof (*__tls_internal.rand_state));
+      free (__tls_internal.rand_state);
+    }
+}
diff --git a/sysdeps/generic/tls-internal.h b/sysdeps/generic/tls-internal.h
index acb8ac9abe..3f53e4a1fa 100644
--- a/sysdeps/generic/tls-internal.h
+++ b/sysdeps/generic/tls-internal.h
@@ -30,11 +30,6 @@ __glibc_tls_internal (void)
   return &__tls_internal;
 }
 
-static inline void
-__glibc_tls_internal_free (void)
-{
-  free (__tls_internal.strsignal_buf);
-  free (__tls_internal.strerror_l_buf);
-}
+extern void __glibc_tls_internal_free (void) attribute_hidden;
 
 #endif
diff --git a/sysdeps/mach/hurd/_Fork.c b/sysdeps/mach/hurd/_Fork.c
index e60b86fab1..667068c8cf 100644
--- a/sysdeps/mach/hurd/_Fork.c
+++ b/sysdeps/mach/hurd/_Fork.c
@@ -662,6 +662,8 @@ retry:
       _hurd_malloc_fork_child ();
       call_function_static_weak (__malloc_fork_unlock_child);
 
+      call_function_static_weak (__arc4random_fork_subprocess);
+
       /* Run things that want to run in the child task to set up.  */
       RUN_HOOK (_hurd_fork_child_hook, ());
 
diff --git a/sysdeps/mach/hurd/i386/libc.abilist b/sysdeps/mach/hurd/i386/libc.abilist
index 66fb0e28fa..4e3200ef55 100644
--- a/sysdeps/mach/hurd/i386/libc.abilist
+++ b/sysdeps/mach/hurd/i386/libc.abilist
@@ -2289,6 +2289,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 close_range F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 mbrtoc8 F
 GLIBC_2.4 __confstr_chk F
diff --git a/sysdeps/mach/hurd/not-cancel.h b/sysdeps/mach/hurd/not-cancel.h
index 6ec92ced84..9a3a7ed59a 100644
--- a/sysdeps/mach/hurd/not-cancel.h
+++ b/sysdeps/mach/hurd/not-cancel.h
@@ -74,6 +74,9 @@ __typeof (__fcntl) __fcntl_nocancel;
 #define __fcntl64_nocancel(...) \
   __fcntl_nocancel (__VA_ARGS__)
 
+#define __getrandom_nocancel(buf, size, flags) \
+  __getrandom (buf, size, flags)
+
 #if IS_IN (libc)
 hidden_proto (__close_nocancel)
 hidden_proto (__close_nocancel_nostatus)
diff --git a/sysdeps/nptl/_Fork.c b/sysdeps/nptl/_Fork.c
index dd568992e2..7dc02569f6 100644
--- a/sysdeps/nptl/_Fork.c
+++ b/sysdeps/nptl/_Fork.c
@@ -43,6 +43,8 @@ _Fork (void)
       self->robust_head.list = &self->robust_head;
       INTERNAL_SYSCALL_CALL (set_robust_list, &self->robust_head,
 			     sizeof (struct robust_list_head));
+
+      call_function_static_weak (__arc4random_fork_subprocess);
     }
   return pid;
 }
diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
index 516b029d30..b66fadef40 100644
--- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
@@ -2616,6 +2616,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/alpha/libc.abilist b/sysdeps/unix/sysv/linux/alpha/libc.abilist
index dde08899fe..f918bb2d48 100644
--- a/sysdeps/unix/sysv/linux/alpha/libc.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/libc.abilist
@@ -2713,6 +2713,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/arc/libc.abilist b/sysdeps/unix/sysv/linux/arc/libc.abilist
index ade44d3029..093043a533 100644
--- a/sysdeps/unix/sysv/linux/arc/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arc/libc.abilist
@@ -2377,6 +2377,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/arm/be/libc.abilist b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
index 98b33708af..e0668a80cf 100644
--- a/sysdeps/unix/sysv/linux/arm/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/be/libc.abilist
@@ -496,6 +496,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/arm/le/libc.abilist b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
index 05dbbe5bcc..d28e7c60b7 100644
--- a/sysdeps/unix/sysv/linux/arm/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/arm/le/libc.abilist
@@ -493,6 +493,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/csky/libc.abilist b/sysdeps/unix/sysv/linux/csky/libc.abilist
index 430a24349e..922b05062f 100644
--- a/sysdeps/unix/sysv/linux/csky/libc.abilist
+++ b/sysdeps/unix/sysv/linux/csky/libc.abilist
@@ -2652,6 +2652,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/hppa/libc.abilist b/sysdeps/unix/sysv/linux/hppa/libc.abilist
index de44616526..412144f94c 100644
--- a/sysdeps/unix/sysv/linux/hppa/libc.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/libc.abilist
@@ -2601,6 +2601,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/i386/libc.abilist b/sysdeps/unix/sysv/linux/i386/libc.abilist
index 18b4fbf26e..134393900a 100644
--- a/sysdeps/unix/sysv/linux/i386/libc.abilist
+++ b/sysdeps/unix/sysv/linux/i386/libc.abilist
@@ -2785,6 +2785,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/ia64/libc.abilist b/sysdeps/unix/sysv/linux/ia64/libc.abilist
index a8e959d417..02c65b6482 100644
--- a/sysdeps/unix/sysv/linux/ia64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/libc.abilist
@@ -2551,6 +2551,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
index 3a7e4ef6e4..0604029c68 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist
@@ -497,6 +497,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
index 864ad2cdf8..af2be5c80d 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist
@@ -2728,6 +2728,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
index 163058420d..e090b8d48f 100644
--- a/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/be/libc.abilist
@@ -2701,6 +2701,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
index a6debfda56..8c5b2db243 100644
--- a/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/le/libc.abilist
@@ -2698,6 +2698,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
index 2b53d888de..68847134a2 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist
@@ -2693,6 +2693,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
index 849aae4130..daa44e64fa 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist
@@ -2691,6 +2691,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
index 37f6c1bf58..6169188c96 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist
@@ -2699,6 +2699,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
index ff1eb91e10..2f7f1ccaf7 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist
@@ -2602,6 +2602,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/nios2/libc.abilist b/sysdeps/unix/sysv/linux/nios2/libc.abilist
index 361b91f547..58e9b486b0 100644
--- a/sysdeps/unix/sysv/linux/nios2/libc.abilist
+++ b/sysdeps/unix/sysv/linux/nios2/libc.abilist
@@ -2740,6 +2740,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/not-cancel.h b/sysdeps/unix/sysv/linux/not-cancel.h
index 75b9e0ee1e..2c58d5ae2f 100644
--- a/sysdeps/unix/sysv/linux/not-cancel.h
+++ b/sysdeps/unix/sysv/linux/not-cancel.h
@@ -67,6 +67,13 @@ __writev_nocancel_nostatus (int fd, const struct iovec *iov, int iovcnt)
   INTERNAL_SYSCALL_CALL (writev, fd, iov, iovcnt);
 }
 
+static inline int
+__getrandom_nocancel (void *buf, size_t buflen, unsigned int flags)
+{
+  return INTERNAL_SYSCALL_CALL (getrandom, buf, buflen, flags);
+}
+
+
 /* Uncancelable fcntl.  */
 __typeof (__fcntl) __fcntl64_nocancel;
 
diff --git a/sysdeps/unix/sysv/linux/or1k/libc.abilist b/sysdeps/unix/sysv/linux/or1k/libc.abilist
index cb91606377..ffdb8819d5 100644
--- a/sysdeps/unix/sysv/linux/or1k/libc.abilist
+++ b/sysdeps/unix/sysv/linux/or1k/libc.abilist
@@ -2123,6 +2123,9 @@ GLIBC_2.35 wprintf F
 GLIBC_2.35 write F
 GLIBC_2.35 writev F
 GLIBC_2.35 wscanf F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
index 1264aff6ef..8c9ca32cbe 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist
@@ -2755,6 +2755,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
index f96d6e37b5..08a6604aab 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist
@@ -2788,6 +2788,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
index e7082e1bd3..849863e639 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/libc.abilist
@@ -2510,6 +2510,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
index 1032c7e46a..b2ccee08c6 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/libc.abilist
@@ -2812,6 +2812,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
index f932db7c22..ff90d1bff2 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv32/libc.abilist
@@ -2379,6 +2379,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
index ccc53b0bb8..f1017f6ec5 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv64/libc.abilist
@@ -2579,6 +2579,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
index dbf6501007..009f22931e 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist
@@ -2753,6 +2753,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
index 98f08a01b6..0e0b3df973 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist
@@ -2547,6 +2547,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/sh/be/libc.abilist b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
index df11cc8f13..afb5bc37b1 100644
--- a/sysdeps/unix/sysv/linux/sh/be/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/be/libc.abilist
@@ -2608,6 +2608,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/sh/le/libc.abilist b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
index 4ee5513d18..2b53a3cf92 100644
--- a/sysdeps/unix/sysv/linux/sh/le/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sh/le/libc.abilist
@@ -2605,6 +2605,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
index 3cefa76871..43b9844a99 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist
@@ -2748,6 +2748,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
index e3ea5c4383..9ec4a0bc7f 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist
@@ -2574,6 +2574,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/tls-internal.c b/sysdeps/unix/sysv/linux/tls-internal.c
index 6e25b021ab..0326ebb767 100644
--- a/sysdeps/unix/sysv/linux/tls-internal.c
+++ b/sysdeps/unix/sysv/linux/tls-internal.c
@@ -1 +1,38 @@
-/* Empty.  */
+/* Per-thread state.  Linux version.
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <stdlib/arc4random.h>
+#include <string.h>
+#include <tls-internal.h>
+
+void
+__glibc_tls_internal_free (void)
+{
+  struct pthread *self = THREAD_SELF;
+  free (self->tls_state.strsignal_buf);
+  free (self->tls_state.strerror_l_buf);
+
+  if (self->tls_state.rand_state != NULL)
+    {
+      /* Clear any lingering random state prior so if the thread stack is
+         cached it won't leak any data.  */
+      explicit_bzero (self->tls_state.rand_state,
+		      sizeof (*self->tls_state.rand_state));
+      free (self->tls_state.rand_state);
+    }
+}
diff --git a/sysdeps/unix/sysv/linux/tls-internal.h b/sysdeps/unix/sysv/linux/tls-internal.h
index f7a1a62135..ebc65d896a 100644
--- a/sysdeps/unix/sysv/linux/tls-internal.h
+++ b/sysdeps/unix/sysv/linux/tls-internal.h
@@ -28,11 +28,7 @@ __glibc_tls_internal (void)
   return &THREAD_SELF->tls_state;
 }
 
-static inline void
-__glibc_tls_internal_free (void)
-{
-  free (THREAD_SELF->tls_state.strsignal_buf);
-  free (THREAD_SELF->tls_state.strerror_l_buf);
-}
+/* Reset the arc4random TCB state on fork.  */
+extern void __glibc_tls_internal_free (void) attribute_hidden;
 
 #endif
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
index 2944bc7837..367c8d0a03 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/libc.abilist
@@ -2525,6 +2525,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
index 47296193af..6a614efb62 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist
@@ -2631,6 +2631,9 @@ GLIBC_2.35 __memcmpeq F
 GLIBC_2.35 _dl_find_object F
 GLIBC_2.35 epoll_pwait2 F
 GLIBC_2.35 posix_spawn_file_actions_addtcsetpgrp_np F
+GLIBC_2.36 arc4random F
+GLIBC_2.36 arc4random_buf F
+GLIBC_2.36 arc4random_uniform F
 GLIBC_2.36 c8rtomb F
 GLIBC_2.36 fsconfig F
 GLIBC_2.36 fsmount F