@@ -17,6 +17,11 @@ Deprecated and removed features, and other changes affecting compatibility:
removal of the LD_TRACE_PRELINKING, and LD_USE_LOAD_BIAS, environment
variables and their functionality in the dynamic loader.
+* The Linux kernel version check has been removed along with the
+ LD_ASSUME_KERNEL environment variable. The minimum kernel used to built
+ glibc is still provided through NT_GNU_ABI_TAG ELF note and also printed
+ when libc.so is issued directly.
+
Changes to build and runtime requirements:
[Add changes to build and runtime requirements here]
@@ -138,6 +138,9 @@
/* Linux specific: minimum supported kernel version. */
#undef __LINUX_KERNEL_VERSION
+/* Linux specific: __LINUX_KERNEL_VERSION as a string. */
+#undef __LINUX_KERNEL_VERSION_STR
+
/* Override abi-tags ABI version if necessary. */
#undef __ABI_TAG_VERSION
@@ -316,14 +316,6 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
__stack_chk_guard = stack_chk_guard;
# endif
-# ifdef DL_SYSDEP_OSCHECK
- {
- /* This needs to run to initiliaze _dl_osversion before TLS
- setup might check it. */
- DL_SYSDEP_OSCHECK (__libc_fatal);
- }
-# endif
-
/* Initialize libpthread if linked in. */
if (__pthread_initialize_minimal != NULL)
__pthread_initialize_minimal ();
@@ -33,6 +33,9 @@ Compiled by GNU CC version "__VERSION__".\n"
#ifdef LIBC_ABIS_STRING
LIBC_ABIS_STRING
#endif
+#ifdef __LINUX_KERNEL_VERSION_STR
+"Minimum supported kernel: " __LINUX_KERNEL_VERSION_STR "\n"
+#endif
"For bug reporting instructions, please see:\n\
"REPORT_BUGS_TO".\n";
@@ -297,9 +297,6 @@ search_cache (const char *string_table, uint32_t string_table_size,
if ((libnew->hwcap & hwcap_exclude) && !named_hwcap)
continue;
- if (GLRO (dl_osversion)
- && libnew->osversion > GLRO (dl_osversion))
- continue;
if (_DL_PLATFORMS_COUNT
&& (libnew->hwcap & _DL_HWCAP_PLATFORM) != 0
&& ((libnew->hwcap & _DL_HWCAP_PLATFORM)
@@ -231,10 +231,6 @@ print_version (void)
void
_dl_print_diagnostics (char **environ)
{
-#ifdef HAVE_DL_DISCOVER_OSVERSION
- _dl_diagnostics_print_labeled_value
- ("dl_discover_osversion", _dl_discover_osversion ());
-#endif
_dl_diagnostics_print_labeled_string ("dl_dst_lib", DL_DST_LIB);
_dl_diagnostics_print_labeled_value ("dl_hwcap", GLRO (dl_hwcap));
_dl_diagnostics_print_labeled_value ("dl_hwcap_important", HWCAP_IMPORTANT);
@@ -243,7 +239,6 @@ _dl_print_diagnostics (char **environ)
("dl_hwcaps_subdirs", _dl_hwcaps_subdirs);
_dl_diagnostics_print_labeled_value
("dl_hwcaps_subdirs_active", _dl_hwcaps_subdirs_active ());
- _dl_diagnostics_print_labeled_value ("dl_osversion", GLRO (dl_osversion));
_dl_diagnostics_print_labeled_value ("dl_pagesize", GLRO (dl_pagesize));
_dl_diagnostics_print_labeled_string ("dl_platform", GLRO (dl_platform));
_dl_diagnostics_print_labeled_string
@@ -1591,13 +1591,6 @@ open_verify (const char *name, int fd,
[EI_OSABI] = ELFOSABI_SYSV,
[EI_ABIVERSION] = 0
};
- static const struct
- {
- ElfW(Word) vendorlen;
- ElfW(Word) datalen;
- ElfW(Word) type;
- char vendor[4];
- } expected_note = { 4, 16, 1, "GNU" };
/* Initialize it to make the compiler happy. */
const char *errstring = NULL;
int errval = 0;
@@ -1628,10 +1621,7 @@ open_verify (const char *name, int fd,
if (fd != -1)
{
ElfW(Ehdr) *ehdr;
- ElfW(Phdr) *phdr, *ph;
- ElfW(Word) *abi_note;
- ElfW(Word) *abi_note_malloced = NULL;
- unsigned int osversion;
+ ElfW(Phdr) *phdr;
size_t maplength;
/* We successfully opened the file. Now verify it is a file
@@ -1695,13 +1685,16 @@ open_verify (const char *name, int fd,
#endif
)
errstring = N_("invalid ELF header");
+
else if (ehdr->e_ident[EI_CLASS] != ELFW(CLASS))
{
/* This is not a fatal error. On architectures where
32-bit and 64-bit binaries can be run this might
happen. */
*found_other_class = true;
- goto close_and_out;
+ __close_nocancel (fd);
+ __set_errno (ENOENT);
+ return -1;
}
else if (ehdr->e_ident[EI_DATA] != byteorder)
{
@@ -1736,7 +1729,11 @@ open_verify (const char *name, int fd,
goto lose;
}
if (! __glibc_likely (elf_machine_matches_host (ehdr)))
- goto close_and_out;
+ {
+ __close_nocancel (fd);
+ __set_errno (ENOENT);
+ return -1;
+ }
else if (__glibc_unlikely (ehdr->e_type != ET_DYN
&& ehdr->e_type != ET_EXEC))
{
@@ -1758,7 +1755,6 @@ open_verify (const char *name, int fd,
if ((size_t) __pread64_nocancel (fd, (void *) phdr, maplength,
ehdr->e_phoff) != maplength)
{
- read_error:
errval = errno;
errstring = N_("cannot read file data");
goto lose;
@@ -1768,73 +1764,12 @@ open_verify (const char *name, int fd,
if (__glibc_unlikely (elf_machine_reject_phdr_p
(phdr, ehdr->e_phnum, fbp->buf, fbp->len,
loader, fd)))
- goto close_and_out;
-
- /* Check .note.ABI-tag if present. */
- for (ph = phdr; ph < &phdr[ehdr->e_phnum]; ++ph)
- if (ph->p_type == PT_NOTE && ph->p_filesz >= 32
- && (ph->p_align == 4 || ph->p_align == 8))
- {
- ElfW(Addr) size = ph->p_filesz;
-
- if (ph->p_offset + size <= (size_t) fbp->len)
- abi_note = (void *) (fbp->buf + ph->p_offset);
- else
- {
- /* Note: __libc_use_alloca is not usable here, because
- thread info may not have been set up yet. */
- if (size < __MAX_ALLOCA_CUTOFF)
- abi_note = alloca (size);
- else
- {
- /* There could be multiple PT_NOTEs. */
- abi_note_malloced = realloc (abi_note_malloced, size);
- if (abi_note_malloced == NULL)
- goto read_error;
-
- abi_note = abi_note_malloced;
- }
- if (__pread64_nocancel (fd, (void *) abi_note, size,
- ph->p_offset) != size)
- {
- free (abi_note_malloced);
- goto read_error;
- }
- }
-
- while (memcmp (abi_note, &expected_note, sizeof (expected_note)))
- {
- ElfW(Addr) note_size
- = ELF_NOTE_NEXT_OFFSET (abi_note[0], abi_note[1],
- ph->p_align);
-
- if (size - 32 < note_size)
- {
- size = 0;
- break;
- }
- size -= note_size;
- abi_note = (void *) abi_note + note_size;
- }
-
- if (size == 0)
- continue;
-
- osversion = (abi_note[5] & 0xff) * 65536
- + (abi_note[6] & 0xff) * 256
- + (abi_note[7] & 0xff);
- if (abi_note[4] != __ABI_TAG_OS
- || (GLRO(dl_osversion) && GLRO(dl_osversion) < osversion))
- {
- close_and_out:
- __close_nocancel (fd);
- __set_errno (ENOENT);
- fd = -1;
- }
+ {
+ __close_nocancel (fd);
+ __set_errno (ENOENT);
+ return -1;
+ }
- break;
- }
- free (abi_note_malloced);
}
return fd;
@@ -145,8 +145,6 @@ size_t _dl_minsigstacksize = CONSTANT_MINSIGSTKSZ;
int _dl_inhibit_cache;
-unsigned int _dl_osversion;
-
/* All known directories in sorted order. */
struct r_search_path_elem *_dl_all_dirs;
@@ -327,10 +325,6 @@ _dl_non_dynamic_init (void)
DL_PLATFORM_INIT;
#endif
-#ifdef DL_OSVERSION_INIT
- DL_OSVERSION_INIT;
-#endif
-
/* Now determine the length of the platform string. */
if (_dl_platform != NULL)
_dl_platformlen = strlen (_dl_platform);
@@ -384,9 +384,6 @@ struct rtld_global_ro _rtld_global_ro attribute_relro =
._dl_error_free = _dl_error_free,
._dl_tls_get_addr_soft = _dl_tls_get_addr_soft,
._dl_libc_freeres = __rtld_libc_freeres,
-#ifdef HAVE_DL_DISCOVER_OSVERSION
- ._dl_discover_osversion = _dl_discover_osversion
-#endif
};
/* If we would use strong_alias here the compiler would see a
non-hidden definition. This would undo the effect of the previous
@@ -1715,10 +1712,6 @@ dl_main (const ElfW(Phdr) *phdr,
/* With vDSO setup we can initialize the function pointers. */
setup_vdso_pointers ();
-#ifdef DL_SYSDEP_OSCHECK
- DL_SYSDEP_OSCHECK (_dl_fatal_printf);
-#endif
-
/* Initialize the data structures for the search paths for shared
objects. */
call_init_paths (&state);
@@ -2644,14 +2637,6 @@ process_envvars (struct dl_main_state *state)
GLRO(dl_dynamic_weak) = 1;
break;
- case 13:
- /* We might have some extra environment variable with length 13
- to handle. */
-#ifdef EXTRA_LD_ENVVARS_13
- EXTRA_LD_ENVVARS_13
-#endif
- break;
-
case 14:
/* Where to place the profiling data file. */
if (!__libc_enable_secure
@@ -563,8 +563,6 @@ struct rtld_global_ro
/* These two are used only internally. */
#define DL_DEBUG_HELP (1 << 10)
- /* OS version. */
- EXTERN unsigned int _dl_osversion;
/* Platform name. */
EXTERN const char *_dl_platform;
EXTERN size_t _dl_platformlen;
@@ -712,10 +710,6 @@ struct rtld_global_ro
dlopen. */
int (*_dl_find_object) (void *, struct dl_find_object *);
-#ifdef HAVE_DL_DISCOVER_OSVERSION
- int (*_dl_discover_osversion) (void);
-#endif
-
/* Dynamic linker operations used after static dlopen. */
const struct dlfcn_hook *_dl_dlfcn_hook;
@@ -70,6 +70,7 @@ fi
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for kernel header at least $minimum_kernel" >&5
$as_echo_n "checking for kernel header at least $minimum_kernel... " >&6; }
decnum=`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/(\1 * 65536 + \2 * 256 + \3)/'`;
+abinumstr=`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\1.\2.\3/'`;
abinum=`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\1,\2,\3/'`;
cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h. */
@@ -96,6 +97,10 @@ $as_echo "$libc_minimum_kernel" >&6; }
if test "$libc_minimum_kernel" = ok; then
cat >>confdefs.h <<_ACEOF
#define __LINUX_KERNEL_VERSION $decnum
+_ACEOF
+
+ cat >>confdefs.h <<_ACEOF
+#define __LINUX_KERNEL_VERSION_STR "$abinumstr"
_ACEOF
cat >>confdefs.h <<_ACEOF
@@ -50,6 +50,7 @@ fi
AC_MSG_CHECKING(for kernel header at least $minimum_kernel)
changequote(,)dnl
decnum=`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/(\1 * 65536 + \2 * 256 + \3)/'`;
+abinumstr=`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\1.\2.\3/'`;
abinum=`echo "$minimum_kernel.0.0.0" | sed 's/\([0-9]*\)\.\([0-9]*\)\.\([0-9]*\).*/\1,\2,\3/'`;
changequote([,])dnl
AC_PREPROC_IFELSE([AC_LANG_PROGRAM([[#include <linux/version.h>
@@ -59,6 +60,7 @@ AC_PREPROC_IFELSE([AC_LANG_PROGRAM([[#include <linux/version.h>
AC_MSG_RESULT($libc_minimum_kernel)
if test "$libc_minimum_kernel" = ok; then
AC_DEFINE_UNQUOTED(__LINUX_KERNEL_VERSION, $decnum)
+ AC_DEFINE_UNQUOTED(__LINUX_KERNEL_VERSION_STR, "$abinumstr")
AC_DEFINE_UNQUOTED(__ABI_TAG_VERSION, $abinum)
else
AC_MSG_ERROR([*** The available kernel headers are older than the requested
deleted file mode 100644
@@ -1,59 +0,0 @@
-/* Optional code to distinguish library flavours.
- Copyright (C) 2001-2022 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 _DL_LIBRECON_H
-#define _DL_LIBRECON_H 1
-
-static inline void __attribute__ ((unused, always_inline))
-_dl_osversion_init (char *assume_kernel)
-{
- unsigned long int i, j, osversion = 0;
- char *p = assume_kernel, *q;
-
- for (i = 0; i < 3; i++, p = q + 1)
- {
- j = _dl_strtoul (p, &q);
- if (j >= 255 || p == q || (i < 2 && *q && *q != '.'))
- {
- osversion = 0;
- break;
- }
- osversion |= j << (16 - 8 * i);
- if (!*q)
- break;
- }
- if (osversion)
- GLRO(dl_osversion) = osversion;
-}
-
-/* Recognizing extra environment variables. */
-#define EXTRA_LD_ENVVARS_13 \
- if (memcmp (envline, "ASSUME_KERNEL", 13) == 0) \
- { \
- _dl_osversion_init (&envline[14]); \
- break; \
- }
-
-#define DL_OSVERSION_INIT \
- do { \
- char *assume_kernel = getenv ("LD_ASSUME_KERNEL"); \
- if (assume_kernel) \
- _dl_osversion_init (assume_kernel); \
- } while (0)
-
-#endif /* dl-librecon.h */
@@ -22,31 +22,6 @@
#include <stdint.h>
#include <not-cancel.h>
-#ifndef MIN
-# define MIN(a,b) (((a)<(b))?(a):(b))
-#endif
-
-#define DL_SYSDEP_OSCHECK(FATAL) \
- do { \
- /* Test whether the kernel is new enough. This test is only performed \
- if the library is not compiled to run on all kernels. */ \
- \
- int version = _dl_discover_osversion (); \
- if (__glibc_likely (version >= 0)) \
- { \
- if (__builtin_expect (GLRO(dl_osversion) == 0, 1) \
- || GLRO(dl_osversion) > version) \
- GLRO(dl_osversion) = version; \
- \
- /* Now we can test with the required version. */ \
- if (__LINUX_KERNEL_VERSION > 0 && version < __LINUX_KERNEL_VERSION) \
- /* Not sufficent. */ \
- FATAL ("FATAL: kernel too old\n"); \
- } \
- else if (__LINUX_KERNEL_VERSION > 0) \
- FATAL ("FATAL: cannot determine kernel version\n"); \
- } while (0)
-
static inline uintptr_t __attribute__ ((always_inline))
_dl_setup_stack_chk_guard (void *dl_random)
{
@@ -250,96 +250,3 @@ _dl_show_auxv (void)
}
#endif /* SHARED */
-
-
-int
-attribute_hidden
-_dl_discover_osversion (void)
-{
-#ifdef SHARED
- if (GLRO(dl_sysinfo_map) != NULL)
- {
- /* If the kernel-supplied DSO contains a note indicating the kernel's
- version, we don't need to call uname or parse any strings. */
-
- static const struct
- {
- ElfW(Nhdr) hdr;
- char vendor[8];
- } expected_note = { { sizeof "Linux", sizeof (ElfW(Word)), 0 }, "Linux" };
- const ElfW(Phdr) *const phdr = GLRO(dl_sysinfo_map)->l_phdr;
- const ElfW(Word) phnum = GLRO(dl_sysinfo_map)->l_phnum;
- for (uint_fast16_t i = 0; i < phnum; ++i)
- if (phdr[i].p_type == PT_NOTE)
- {
- const ElfW(Addr) start = (phdr[i].p_vaddr
- + GLRO(dl_sysinfo_map)->l_addr);
- const ElfW(Nhdr) *note = (const void *) start;
- while ((ElfW(Addr)) (note + 1) - start < phdr[i].p_memsz)
- {
- if (!memcmp (note, &expected_note, sizeof expected_note))
- return *(const ElfW(Word) *) ((const void *) note
- + sizeof expected_note);
-#define ROUND(len) (((len) + sizeof note->n_type - 1) & -sizeof note->n_type)
- note = ((const void *) (note + 1)
- + ROUND (note->n_namesz) + ROUND (note->n_descsz));
-#undef ROUND
- }
- }
- }
-#endif /* SHARED */
-
- char bufmem[64];
- char *buf = bufmem;
- unsigned int version;
- int parts;
- char *cp;
- struct utsname uts;
-
- /* Try the uname system call. */
- if (__uname (&uts))
- {
- /* This was not successful. Now try reading the /proc filesystem. */
- int fd = __open64_nocancel ("/proc/sys/kernel/osrelease", O_RDONLY);
- if (fd < 0)
- return -1;
- ssize_t reslen = __read_nocancel (fd, bufmem, sizeof (bufmem));
- __close_nocancel (fd);
- if (reslen <= 0)
- /* This also didn't work. We give up since we cannot
- make sure the library can actually work. */
- return -1;
- buf[MIN (reslen, (ssize_t) sizeof (bufmem) - 1)] = '\0';
- }
- else
- buf = uts.release;
-
- /* Now convert it into a number. The string consists of at most
- three parts. */
- version = 0;
- parts = 0;
- cp = buf;
- while ((*cp >= '0') && (*cp <= '9'))
- {
- unsigned int here = *cp++ - '0';
-
- while ((*cp >= '0') && (*cp <= '9'))
- {
- here *= 10;
- here += *cp++ - '0';
- }
-
- ++parts;
- version <<= 8;
- version |= here;
-
- if (*cp++ != '.' || parts == 3)
- /* Another part following? */
- break;
- }
-
- if (parts < 3)
- version <<= 8 * (3 - parts);
-
- return version;
-}
@@ -24,10 +24,3 @@
we aren't making direct use of it. So enable this across the board. */
#define NEED_DL_SYSINFO_DSO 1
-
-
-#ifndef __ASSEMBLER__
-/* Get version of the OS. */
-extern int _dl_discover_osversion (void) attribute_hidden;
-# define HAVE_DL_DISCOVER_OSVERSION 1
-#endif
@@ -18,8 +18,6 @@
#ifndef _DL_LIBRECON_H
-#include <sysdeps/unix/sysv/linux/dl-librecon.h>
-
#define DISTINGUISH_LIB_VERSIONS \
do \
{ \