This synchronization method has a lower overhead and makes
it more likely that the signal arrives during one of the critical
functions.

Also test for fork deadlocks explicitly.

The memusagestat is the only binary that has its own link line which
causes it to be linked against the existing installed C library.  It
has been this way since it was originally committed in 1999, but I
don't see any reason as to why.  Since we want all the programs we
build locally to be against the new copy of glibc, change the build
to be like all other programs.

Remove do_set_mallopt_check prototype since it is unused.

	* malloc/arena.c (do_set_mallopt_check): Removed.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: DJ Delorie <dj@redhat.com>

As discussed previously on libc-alpha [1], this patch follows up the idea
and add both the __attribute_alloc_size__ on malloc functions (malloc,
calloc, realloc, reallocarray, valloc, pvalloc, and memalign) and limit
maximum requested allocation size to up PTRDIFF_MAX (taking into
consideration internal padding and alignment).

This aligns glibc with gcc expected size defined by default warning
-Walloc-size-larger-than value which warns for allocation larger than
PTRDIFF_MAX.  It also aligns with gcc expectation regarding libc and
expected size, such as described in PR#67999 [2] and previously discussed
ISO C11 issues [3] on libc-alpha.

From the RFC thread [4] and previous discussion, it seems that consensus
is only to limit such requested size for malloc functions, not the system
allocation one (mmap, sbrk, etc.).

The implementation changes checked_request2size to check for both overflow
and maximum object size up to PTRDIFF_MAX. No additional checks are done
on sysmalloc, so it can still issue mmap with values larger than
PTRDIFF_T depending on the requested size.

The __attribute_alloc_size__ is for functions that return a pointer only,
which means it cannot be applied to posix_memalign (see remarks in GCC
PR#87683 [5]). The runtimes checks to limit maximum requested allocation
size does applies to posix_memalign.

Checked on x86_64-linux-gnu and i686-linux-gnu.

[1] https://sourceware.org/ml/libc-alpha/2018-11/msg00223.html
[2] https://gcc.gnu.org/bugzilla//show_bug.cgi?id=67999
[3] https://sourceware.org/ml/libc-alpha/2011-12/msg00066.html
[4] https://sourceware.org/ml/libc-alpha/2018-11/msg00224.html
[5] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87683

	[BZ #23741]
	* malloc/hooks.c (malloc_check, realloc_check): Use
	__builtin_add_overflow on overflow check and adapt to
	checked_request2size change.
	* malloc/malloc.c (__libc_malloc, __libc_realloc, _mid_memalign,
	__libc_pvalloc, __libc_calloc, _int_memalign): Limit maximum
	allocation size to PTRDIFF_MAX.
	(REQUEST_OUT_OF_RANGE): Remove macro.
	(checked_request2size): Change to inline function and limit maximum
	requested size to PTRDIFF_MAX.
	(__libc_malloc, __libc_realloc, _int_malloc, _int_memalign): Limit
	maximum allocation size to PTRDIFF_MAX.
	(_mid_memalign): Use _int_memalign call for overflow check.
	(__libc_pvalloc): Use __builtin_add_overflow on overflow check.
	(__libc_calloc): Use __builtin_mul_overflow for overflow check and
	limit maximum requested size to PTRDIFF_MAX.
	* malloc/malloc.h (malloc, calloc, realloc, reallocarray, memalign,
	valloc, pvalloc): Add __attribute_alloc_size__.
	* stdlib/stdlib.h (malloc, realloc, reallocarray, valloc): Likewise.
	* malloc/tst-malloc-too-large.c (do_test): Add check for allocation
	larger than PTRDIFF_MAX.
	* malloc/tst-memalign.c (do_test): Disable -Walloc-size-larger-than=
	around tests of malloc with negative sizes.
	* malloc/tst-posix_memalign.c (do_test): Likewise.
	* malloc/tst-pvalloc.c (do_test): Likewise.
	* malloc/tst-valloc.c (do_test): Likewise.
	* malloc/tst-reallocarray.c (do_test): Replace call to reallocarray
	with resulting size allocation larger than PTRDIFF_MAX with
	reallocarray_nowarn.
	(reallocarray_nowarn): New function.
	* NEWS: Mention the malloc function semantic change.

If an error occurs during the tracing operation, particularly during a
call to lock_and_info() which calls _dl_addr, we may end up calling back
into the malloc-subsystem and relock the loader lock and deadlock. For
all intents and purposes the call to _dl_addr can call any of the malloc
family API functions and so we should disable all tracing before calling
such loader functions.  This is similar to the strategy that the new
malloc tracer takes when calling the real malloc, namely that all
tracing ceases at the boundary to the real function and any faults at
that point are the purvue of the library (though the new tracer does
this on a per-thread basis in an MT-safe fashion). Since the new tracer
and the hook deprecation are not yet complete we must fix these issues
where we can.

Tested on x86_64 with no regressions.

Co-authored-by: Kwok Cheung Yeung <kcy@codesourcery.com>
Reviewed-by: DJ Delorie <dj@redhat.com>

Fixes bug 24216. This patch adds security checks for bk and bk_nextsize pointers
of chunks in large bin when inserting chunk from unsorted bin. It was possible
to write the pointer to victim (newly inserted chunk) to arbitrary memory
locations if bk or bk_nextsize pointers of the next large bin chunk
got corrupted.

This patch makes further coding style fixes where code was breaking
lines after an operator, contrary to the GNU Coding Standards.  As
with the previous patch, it is limited to files following a reasonable
approximation to GNU style already, and is not exhaustive; more such
issues remain to be fixed.

Tested for x86_64, and with build-many-glibcs.py.

	* dirent/dirent.h [!_DIRENT_HAVE_D_NAMLEN
	&& _DIRENT_HAVE_D_RECLEN] (_D_ALLOC_NAMLEN): Break lines before
	rather than after operators.
	* elf/cache.c (print_cache): Likewise.
	* gshadow/fgetsgent_r.c (__fgetsgent_r): Likewise.
	* htl/pt-getattr.c (__pthread_getattr_np): Likewise.
	* hurd/hurdinit.c (_hurd_setproc): Likewise.
	* hurd/hurdkill.c (_hurd_sig_post): Likewise.
	* hurd/hurdlookup.c (__file_name_lookup_under): Likewise.
	* hurd/hurdsig.c (_hurd_internal_post_signal): Likewise.
	(reauth_proc): Likewise.
	* hurd/lookup-at.c (__file_name_lookup_at): Likewise.
	(__file_name_split_at): Likewise.
	(__directory_name_split_at): Likewise.
	* hurd/lookup-retry.c (__hurd_file_name_lookup_retry): Likewise.
	* hurd/port2fd.c (_hurd_port2fd): Likewise.
	* iconv/gconv_dl.c (do_print): Likewise.
	* inet/netinet/in.h (struct sockaddr_in): Likewise.
	* libio/wstrops.c (_IO_wstr_seekoff): Likewise.
	* locale/setlocale.c (new_composite_name): Likewise.
	* malloc/memusagestat.c (main): Likewise.
	* misc/fstab.c (fstab_convert): Likewise.
	* nptl/pthread_mutex_unlock.c (__pthread_mutex_unlock_usercnt):
	Likewise.
	* nss/nss_compat/compat-grp.c (getgrent_next_nss): Likewise.
	(getgrent_next_file): Likewise.
	(internal_getgrnam_r): Likewise.
	(internal_getgrgid_r): Likewise.
	* nss/nss_compat/compat-initgroups.c (getgrent_next_nss):
	Likewise.
	(internal_getgrent_r): Likewise.
	* nss/nss_compat/compat-pwd.c (getpwent_next_nss_netgr): Likewise.
	(getpwent_next_nss): Likewise.
	(getpwent_next_file): Likewise.
	(internal_getpwnam_r): Likewise.
	(internal_getpwuid_r): Likewise.
	* nss/nss_compat/compat-spwd.c (getspent_next_nss_netgr):
	Likewise.
	(getspent_next_nss): Likewise.
	(internal_getspnam_r): Likewise.
	* pwd/fgetpwent_r.c (__fgetpwent_r): Likewise.
	* shadow/fgetspent_r.c (__fgetspent_r): Likewise.
	* string/strchr.c (STRCHR): Likewise.
	* string/strchrnul.c (STRCHRNUL): Likewise.
	* sysdeps/aarch64/fpu/fpu_control.h (_FPU_FPCR_IEEE): Likewise.
	* sysdeps/aarch64/sfp-machine.h (_FP_CHOOSENAN): Likewise.
	* sysdeps/csky/dl-machine.h (elf_machine_rela): Likewise.
	* sysdeps/generic/memcopy.h (PAGE_COPY_FWD_MAYBE): Likewise.
	* sysdeps/generic/symbol-hacks.h (__stack_chk_fail_local):
	Likewise.
	* sysdeps/gnu/netinet/ip_icmp.h (ICMP_INFOTYPE): Likewise.
	* sysdeps/gnu/updwtmp.c (TRANSFORM_UTMP_FILE_NAME): Likewise.
	* sysdeps/gnu/utmp_file.c (TRANSFORM_UTMP_FILE_NAME): Likewise.
	* sysdeps/hppa/jmpbuf-unwind.h (_JMPBUF_UNWINDS): Likewise.
	* sysdeps/mach/hurd/bits/stat.h (S_ISPARE): Likewise.
	* sysdeps/mach/hurd/dl-sysdep.c (_dl_sysdep_start): Likewise.
	(open_file): Likewise.
	* sysdeps/mach/hurd/htl/pt-mutexattr-setprotocol.c
	(pthread_mutexattr_setprotocol): Likewise.
	* sysdeps/mach/hurd/ioctl.c (__ioctl): Likewise.
	* sysdeps/mach/hurd/mmap.c (__mmap): Likewise.
	* sysdeps/mach/hurd/ptrace.c (ptrace): Likewise.
	* sysdeps/mach/hurd/spawni.c (__spawni): Likewise.
	* sysdeps/microblaze/dl-machine.h (elf_machine_type_class):
	Likewise.
	(elf_machine_rela): Likewise.
	* sysdeps/mips/mips32/sfp-machine.h (_FP_CHOOSENAN): Likewise.
	* sysdeps/mips/mips64/sfp-machine.h (_FP_CHOOSENAN): Likewise.
	* sysdeps/mips/sys/asm.h (multiple #if conditionals): Likewise.
	* sysdeps/posix/rename.c (rename): Likewise.
	* sysdeps/powerpc/novmx-sigjmp.c (__novmx__sigjmp_save): Likewise.
	* sysdeps/powerpc/sigjmp.c (__vmx__sigjmp_save): Likewise.
	* sysdeps/s390/fpu/fenv_libc.h (FPC_VALID_MASK): Likewise.
	* sysdeps/s390/utf8-utf16-z9.c (gconv_end): Likewise.
	* sysdeps/unix/grantpt.c (grantpt): Likewise.
	* sysdeps/unix/sysv/linux/a.out.h (N_TXTOFF): Likewise.
	* sysdeps/unix/sysv/linux/updwtmp.c (TRANSFORM_UTMP_FILE_NAME):
	Likewise.
	* sysdeps/unix/sysv/linux/utmp_file.c (TRANSFORM_UTMP_FILE_NAME):
	Likewise.
	* sysdeps/x86/cpu-features.c (get_common_indices): Likewise.
	* time/tzfile.c (__tzfile_compute): Likewise.

One group of warnings seen with -Wextra is warnings for static or
inline not at the start of a declaration (-Wold-style-declaration).

This patch fixes various such cases for inline, ensuring it comes at
the start of the declaration (after any static).  A common case of the
fix is "static inline <type> __always_inline"; the definition of
__always_inline starts with __inline, so the natural change is to
"static __always_inline <type>".  Other cases of the warning may be
harder to fix (one pattern is a function definition that gets
rewritten to be static by an including file, "#define funcname static
wrapped_funcname" or similar), but it seems worth fixing these cases
with inline anyway.

Tested for x86_64.

	* elf/dl-load.h (_dl_postprocess_loadcmd): Use __always_inline
	before return type, without separate inline.
	* elf/dl-tunables.c (maybe_enable_malloc_check): Likewise.
	* elf/dl-tunables.h (tunable_is_name): Likewise.
	* malloc/malloc.c (do_set_trim_threshold): Likewise.
	(do_set_top_pad): Likewise.
	(do_set_mmap_threshold): Likewise.
	(do_set_mmaps_max): Likewise.
	(do_set_mallopt_check): Likewise.
	(do_set_perturb_byte): Likewise.
	(do_set_arena_test): Likewise.
	(do_set_arena_max): Likewise.
	(do_set_tcache_max): Likewise.
	(do_set_tcache_count): Likewise.
	(do_set_tcache_unsorted_limit): Likewise.
	* nis/nis_subr.c (count_dots): Likewise.
	* nptl/allocatestack.c (advise_stack_range): Likewise.
	* sysdeps/ieee754/dbl-64/s_sin.c (do_cos): Likewise.
	(do_sin): Likewise.
	(reduce_sincos): Likewise.
	(do_sincos): Likewise.
	* sysdeps/unix/sysv/linux/x86/elision-conf.c
	(do_set_elision_enable): Likewise.
	(TUNABLE_CALLBACK_FNDECL): Likewise.

One of the warnings that appears with -Wextra is "ordered comparison
of pointer with integer zero" in malloc.c:tcache_get, for the
assertion:

  assert (tcache->entries[tc_idx] > 0);

Indeed, a "> 0" comparison does not make sense for
tcache->entries[tc_idx], which is a pointer.  My guess is that
tcache->counts[tc_idx] is what's intended here, and this patch changes
the assertion accordingly.

Tested for x86_64.

	* malloc/malloc.c (tcache_get): Compare tcache->counts[tc_idx]
	with 0, not tcache->entries[tc_idx].

Commit 6923f6db1e688dedcf3a6556da76e0bf24a41872 ("malloc: Use current
(C11-style) atomics for fastbin access") caused a substantial
performance regression on POWER and Aarch64, and the old atomics,
while hard to prove correct, seem to work in practice.