@@ -20,7 +20,9 @@ Major new features:
Deprecated and removed features, and other changes affecting compatibility:
- [Add deprecations, removals and changes affecting compatibility here]
+* The getentropy function now follows POSIX 2024, which means that
+ unsupportd large buffer will return EINVAL and the function will
+ abort the process if there is no entropy available in the system.
Changes to build and runtime requirements:
@@ -73,7 +73,7 @@ used by this function was added to the Linux kernel in version 3.17.)
The combination of @var{buffer} and @var{length} arguments specifies
an invalid memory range.
-@item EIO
+@item EINVAL
@var{length} is larger than 256, or the kernel entropy pool has
suffered a catastrophic failure.
@end table
@@ -281,6 +281,7 @@ tests := \
tst-environ-change-2 \
tst-environ-change-3 \
tst-environ-change-4 \
+ tst-getentropy \
tst-getenv-signal \
tst-getenv-static \
tst-getenv-thread \
@@ -392,6 +393,13 @@ tests += \
# tests
endif
+# Test for the getentropy symbol versions required for POSIX 2024
+ifeq ($(have-GLIBC_2.42)$(build-shared),yesyes)
+tests += \
+ tst-getentropy-compat \
+ # tests
+endif
+
LDLIBS-test-atexit-race = $(shared-thread-library)
LDLIBS-test-at_quick_exit-race = $(shared-thread-library)
LDLIBS-test-cxa_atexit-race = $(shared-thread-library)
@@ -223,6 +223,9 @@ libc {
stdc_bit_ceil_ul;
stdc_bit_ceil_ull;
}
+ GLIBC_2.42 {
+ getentropy;
+ }
GLIBC_PRIVATE {
# functions which have an additional interface since they are
# are cancelable.
@@ -16,16 +16,72 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include <sys/random.h>
+#include <stdio.h>
#include <errno.h>
+#include <not-cancel.h>
+#include <sys/random.h>
+#include <shlib-compat.h>
+
+static void
+getentropy_fatal (void)
+{
+ __libc_fatal ("Fatal glibc error: cannot get entropy for getentropy\n");
+}
/* Write LENGTH bytes of randomness starting at BUFFER. Return 0 on
success and -1 on failure. */
-int
-getentropy (void *buffer, size_t length)
+static int
+getentropy_base (void *buffer, size_t length, int err)
{
- __set_errno (ENOSYS);
- return -1;
+ if (length > 256)
+ {
+ __set_errno (err);
+ return -1;
+ }
+
+ /* Try to fill the buffer completely. Even with the 256 byte limit
+ above, we might still receive an EINTR error (when blocking
+ during boot). */
+ void *end = buffer + length;
+ while (buffer < end)
+ {
+ /* NB: No cancellation point. */
+ ssize_t bytes = __getrandom_nocancel (buffer, end - buffer, 0);
+ if (bytes < 0)
+ {
+ switch (errno)
+ {
+ case EINTR:
+ continue;
+ case ENOSYS:
+ return -1;
+ default:
+ getentropy_fatal ();
+ }
+ }
+ else if (bytes == 0)
+ /* No more bytes available. This should not happen under normal
+ circumstances. */
+ getentropy_fatal ();
+
+ /* Try again in case of a short read. */
+ buffer += bytes;
+ }
+ return 0;
}
-stub_warning (getentropy)
+int
+__new_getentropy (void *buffer, size_t length)
+{
+ return getentropy_base (buffer, length, EINVAL);
+}
+versioned_symbol (libc, __new_getentropy, getentropy, GLIBC_2_42);
+
+#if SHLIB_COMPAT (libc, GLIBC_2_25, GLIBC_2_42)
+int
+__old_getentropy (void *buffer, size_t length)
+{
+ return getentropy_base (buffer, length, EIO);
+}
+compat_symbol (libc, __old_getentropy, getentropy, GLIBC_2_25);
+#endif
new file mode 100644
@@ -0,0 +1,26 @@
+/* Compat tests for the getentropy function.
+ Copyright (C) 2016-2025 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 <sys/random.h>
+
+#include <shlib-compat.h>
+
+compat_symbol_reference (libc, getentropy, getentropy, GLIBC_2_25);
+
+#define ERRNO_BUFFER_TO_LARGE EIO
+#include "tst-getentropy.c"
new file mode 100644
@@ -0,0 +1,108 @@
+/* Tests for the getentropy function.
+ Copyright (C) 2016-2025 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 <errno.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/random.h>
+
+#ifndef ERRNO_BUFFER_TO_LARGE
+# define ERRNO_BUFFER_TO_LARGE EINVAL
+#endif
+
+/* Set to true if any errors are encountered. */
+static bool errors;
+
+static void
+test_getentropy (void)
+{
+ char buf[16];
+ memset (buf, '@', sizeof (buf));
+ if (getentropy (buf, 0) != 0)
+ {
+ printf ("error: getentropy zero length: %m\n");
+ errors = true;
+ return;
+ }
+ for (size_t i = 0; i < sizeof (buf); ++i)
+ if (buf[i] != '@')
+ {
+ printf ("error: getentropy modified zero-length buffer\n");
+ errors = true;
+ return;
+ }
+
+ if (getentropy (buf, sizeof (buf)) != 0)
+ {
+ printf ("error: getentropy buf: %m\n");
+ errors = true;
+ return;
+ }
+
+ char buf2[256];
+ _Static_assert (sizeof (buf) < sizeof (buf2), "buf and buf2 compatible");
+ memset (buf2, '@', sizeof (buf2));
+ if (getentropy (buf2, sizeof (buf)) != 0)
+ {
+ printf ("error: getentropy buf2: %m\n");
+ errors = true;
+ return;
+ }
+
+ /* The probability that these two buffers are equal is very
+ small. */
+ if (memcmp (buf, buf2, sizeof (buf)) == 0)
+ {
+ printf ("error: getentropy appears to return constant bytes\n");
+ errors = true;
+ return;
+ }
+
+ for (size_t i = sizeof (buf); i < sizeof (buf2); ++i)
+ if (buf2[i] != '@')
+ {
+ printf ("error: getentropy wrote beyond the end of the buffer\n");
+ errors = true;
+ return;
+ }
+
+ char buf3[257];
+ if (getentropy (buf3, sizeof (buf3)) == 0)
+ {
+ printf ("error: getentropy successful for 257 byte buffer\n");
+ errors = true;
+ return;
+ }
+ if (errno != ERRNO_BUFFER_TO_LARGE)
+ {
+ printf ("error: getentropy wrong error for 257 byte buffer: %m\n");
+ errors = true;
+ return;
+ }
+}
+
+static int
+do_test (void)
+{
+ test_getentropy ();
+
+ return errors;
+}
+
+#include <support/test-driver.c>
@@ -1,4 +1,4 @@
-/* Tests for the getentropy, getrandom functions.
+/* Tests for the getrandom functions.
Copyright (C) 2016-2025 Free Software Foundation, Inc.
This file is part of the GNU C Library.
@@ -151,73 +151,6 @@ test_flags (unsigned int flags)
}
}
-static void
-test_getentropy (void)
-{
- char buf[16];
- memset (buf, '@', sizeof (buf));
- if (getentropy (buf, 0) != 0)
- {
- printf ("error: getentropy zero length: %m\n");
- errors = true;
- return;
- }
- for (size_t i = 0; i < sizeof (buf); ++i)
- if (buf[i] != '@')
- {
- printf ("error: getentropy modified zero-length buffer\n");
- errors = true;
- return;
- }
-
- if (getentropy (buf, sizeof (buf)) != 0)
- {
- printf ("error: getentropy buf: %m\n");
- errors = true;
- return;
- }
-
- char buf2[256];
- _Static_assert (sizeof (buf) < sizeof (buf2), "buf and buf2 compatible");
- memset (buf2, '@', sizeof (buf2));
- if (getentropy (buf2, sizeof (buf)) != 0)
- {
- printf ("error: getentropy buf2: %m\n");
- errors = true;
- return;
- }
-
- /* The probability that these two buffers are equal is very
- small. */
- if (memcmp (buf, buf2, sizeof (buf)) == 0)
- {
- printf ("error: getentropy appears to return constant bytes\n");
- errors = true;
- return;
- }
-
- for (size_t i = sizeof (buf); i < sizeof (buf2); ++i)
- if (buf2[i] != '@')
- {
- printf ("error: getentropy wrote beyond the end of the buffer\n");
- errors = true;
- return;
- }
-
- char buf3[257];
- if (getentropy (buf3, sizeof (buf3)) == 0)
- {
- printf ("error: getentropy successful for 257 byte buffer\n");
- errors = true;
- return;
- }
- if (errno != EIO)
- {
- printf ("error: getentropy wrong error for 257 byte buffer: %m\n");
- errors = true;
- return;
- }
-}
static int
do_test (void)
@@ -237,8 +170,6 @@ do_test (void)
test_flags (flags);
}
- test_getentropy ();
-
return errors;
}
deleted file mode 100644
@@ -1,59 +0,0 @@
-/* Implementation of getentropy based on getrandom.
- Copyright (C) 2016-2025 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 <sys/random.h>
-#include <assert.h>
-#include <errno.h>
-#include <unistd.h>
-#include <hurd.h>
-
-/* Write LENGTH bytes of randomness starting at BUFFER. Return 0 on
- success and -1 on failure. */
-int
-getentropy (void *buffer, size_t length)
-{
- /* The interface is documented to return EIO for buffer lengths
- longer than 256 bytes. */
- if (length > 256)
- return __hurd_fail (EIO);
-
- /* Try to fill the buffer completely. Even with the 256 byte limit
- above, we might still receive an EINTR error (when blocking
- during boot). */
- void *end = buffer + length;
- while (buffer < end)
- {
- /* NB: No cancellation point. */
- ssize_t bytes = __getrandom (buffer, end - buffer, 0);
- if (bytes < 0)
- {
- if (errno == EINTR)
- /* Try again if interrupted by a signal. */
- continue;
- else
- return -1;
- }
- if (bytes == 0)
- /* No more bytes available. This should not happen under
- normal circumstances. */
- return __hurd_fail (EIO);
- /* Try again in case of a short read. */
- buffer += bytes;
- }
- return 0;
-}
@@ -686,7 +686,7 @@ GLIBC_2.2.6 _libc_intl_domainname D 0x5
GLIBC_2.2.6 _longjmp F
GLIBC_2.2.6 _mcleanup F
GLIBC_2.2.6 _mcount F
-GLIBC_2.2.6 _nl_default_dirname D 0xe
+GLIBC_2.2.6 _nl_default_dirname D 0x12
GLIBC_2.2.6 _nl_domain_bindings D 0x4
GLIBC_2.2.6 _nl_msg_cat_cntr D 0x4
GLIBC_2.2.6 _null_auth D 0xc
@@ -2586,6 +2586,7 @@ GLIBC_2.41 pthread_mutexattr_settype F
GLIBC_2.41 pthread_sigmask F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_barrier_destroy F
GLIBC_2.42 pthread_barrier_init F
GLIBC_2.42 pthread_barrier_wait F
@@ -2269,6 +2269,7 @@ GLIBC_2.41 pthread_mutexattr_settype F
GLIBC_2.41 pthread_sigmask F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_barrier_destroy F
GLIBC_2.42 pthread_barrier_init F
GLIBC_2.42 pthread_barrier_wait F
@@ -2752,4 +2752,5 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
@@ -3099,6 +3099,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2513,4 +2513,5 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
@@ -2805,6 +2805,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2802,6 +2802,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2789,4 +2789,5 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
deleted file mode 100644
@@ -1,65 +0,0 @@
-/* Implementation of getentropy based on the getrandom system call.
- Copyright (C) 2016-2025 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 <sys/random.h>
-#include <assert.h>
-#include <errno.h>
-#include <unistd.h>
-#include <sysdep.h>
-
-/* Write LENGTH bytes of randomness starting at BUFFER. Return 0 on
- success and -1 on failure. */
-int
-getentropy (void *buffer, size_t length)
-{
- /* The interface is documented to return EIO for buffer lengths
- longer than 256 bytes. */
- if (length > 256)
- {
- __set_errno (EIO);
- return -1;
- }
-
- /* Try to fill the buffer completely. Even with the 256 byte limit
- above, we might still receive an EINTR error (when blocking
- during boot). */
- void *end = buffer + length;
- while (buffer < end)
- {
- /* NB: No cancellation point. */
- ssize_t bytes = INLINE_SYSCALL_CALL (getrandom, buffer, end - buffer, 0);
- if (bytes < 0)
- {
- if (errno == EINTR)
- /* Try again if interrupted by a signal. */
- continue;
- else
- return -1;
- }
- if (bytes == 0)
- {
- /* No more bytes available. This should not happen under
- normal circumstances. */
- __set_errno (EIO);
- return -1;
- }
- /* Try again in case of a short read. */
- buffer += bytes;
- }
- return 0;
-}
@@ -2826,6 +2826,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -3009,6 +3009,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2273,4 +2273,5 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
@@ -2785,6 +2785,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2952,6 +2952,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2838,4 +2838,5 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
@@ -2835,4 +2835,5 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
@@ -2913,6 +2913,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2919,6 +2919,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2821,6 +2821,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2263,4 +2263,5 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
@@ -3142,6 +3142,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -3187,6 +3187,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2896,6 +2896,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2972,4 +2972,5 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
@@ -2516,4 +2516,5 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
@@ -2716,4 +2716,5 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
@@ -3140,6 +3140,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2933,6 +2933,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2832,6 +2832,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2829,6 +2829,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -3161,6 +3161,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2797,6 +2797,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2748,6 +2748,7 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
GLIBC_2.5 __readlinkat_chk F
GLIBC_2.5 inet6_opt_append F
@@ -2767,4 +2767,5 @@ GLIBC_2.41 sched_getattr F
GLIBC_2.41 sched_setattr F
GLIBC_2.42 __inet_ntop_chk F
GLIBC_2.42 __inet_pton_chk F
+GLIBC_2.42 getentropy F
GLIBC_2.42 pthread_gettid_np F
POSIX.1-2024 added getentropy with some slight different semantics: 1. Buffer larger than 256 (GETENTROPY_MAX) should return EINVAL insted of EIO. 2. There is no defined error if no entropy could be obtained. It means that the function should not fail. For change 1. a new compat symbol is added to return EIO for large buffer, while for 2. both old and new symbol will abort the process. Running an older application on a newer glibc should bring about the security benefits of the new glibc, and recent kernels on most architecture do ensure that getrandom will always return at least 256 bytes of entropy (there are projects like Haveged for the case where kernel can not provide such guarantee). This patch does not move getentropy definition to unistd.h not add GETENTROPY_MAX on limits.h, since glibc still does not have a preprocessor handling for POSIX 2024. The consolidation uses __getrandom_nocancel, which might uses the vDSO implementation if supported. Checked on x86_64-linux-gnu. -- Changes from v1: * Added a compat symbol to handle the EIO->EINVAL change. * Move getentropy tests from tst-getrandom.c to tst-getentropy.c and added a compat test. --- NEWS | 4 +- manual/crypt.texi | 2 +- stdlib/Makefile | 8 ++ stdlib/Versions | 3 + stdlib/getentropy.c | 68 ++++++++++- stdlib/tst-getentropy-compat.c | 26 +++++ stdlib/tst-getentropy.c | 108 ++++++++++++++++++ stdlib/tst-getrandom.c | 71 +----------- sysdeps/mach/hurd/getentropy.c | 59 ---------- sysdeps/mach/hurd/i386/libc.abilist | 3 +- sysdeps/mach/hurd/x86_64/libc.abilist | 1 + sysdeps/unix/sysv/linux/aarch64/libc.abilist | 1 + sysdeps/unix/sysv/linux/alpha/libc.abilist | 1 + sysdeps/unix/sysv/linux/arc/libc.abilist | 1 + sysdeps/unix/sysv/linux/arm/be/libc.abilist | 1 + sysdeps/unix/sysv/linux/arm/le/libc.abilist | 1 + sysdeps/unix/sysv/linux/csky/libc.abilist | 1 + sysdeps/unix/sysv/linux/getentropy.c | 65 ----------- sysdeps/unix/sysv/linux/hppa/libc.abilist | 1 + sysdeps/unix/sysv/linux/i386/libc.abilist | 1 + .../sysv/linux/loongarch/lp64/libc.abilist | 1 + .../sysv/linux/m68k/coldfire/libc.abilist | 1 + .../unix/sysv/linux/m68k/m680x0/libc.abilist | 1 + .../sysv/linux/microblaze/be/libc.abilist | 1 + .../sysv/linux/microblaze/le/libc.abilist | 1 + .../sysv/linux/mips/mips32/fpu/libc.abilist | 1 + .../sysv/linux/mips/mips64/n32/libc.abilist | 1 + .../sysv/linux/mips/mips64/n64/libc.abilist | 1 + sysdeps/unix/sysv/linux/or1k/libc.abilist | 1 + .../linux/powerpc/powerpc32/fpu/libc.abilist | 1 + .../powerpc/powerpc32/nofpu/libc.abilist | 1 + .../linux/powerpc/powerpc64/be/libc.abilist | 1 + .../linux/powerpc/powerpc64/le/libc.abilist | 1 + .../unix/sysv/linux/riscv/rv32/libc.abilist | 1 + .../unix/sysv/linux/riscv/rv64/libc.abilist | 1 + .../unix/sysv/linux/s390/s390-32/libc.abilist | 1 + .../unix/sysv/linux/s390/s390-64/libc.abilist | 1 + sysdeps/unix/sysv/linux/sh/be/libc.abilist | 1 + sysdeps/unix/sysv/linux/sh/le/libc.abilist | 1 + .../sysv/linux/sparc/sparc32/libc.abilist | 1 + .../sysv/linux/sparc/sparc64/libc.abilist | 1 + .../unix/sysv/linux/x86_64/64/libc.abilist | 1 + .../unix/sysv/linux/x86_64/x32/libc.abilist | 1 + 43 files changed, 246 insertions(+), 203 deletions(-) create mode 100644 stdlib/tst-getentropy-compat.c create mode 100644 stdlib/tst-getentropy.c delete mode 100644 sysdeps/mach/hurd/getentropy.c delete mode 100644 sysdeps/unix/sysv/linux/getentropy.c