To support Shadow Stack (SHSTK) in Intel Control-flow Enforcement
Technology (CET) in setjmp/longjmp, we need to save shadow stack
pointer in jmp_buf. The __saved_mask field in jmp_buf has type
of __sigset_t. On Linux, __sigset_t is defined as
#define _SIGSET_NWORDS (1024 / (8 * sizeof (unsigned long int)))
typedef struct
{
unsigned long int __val[_SIGSET_NWORDS];
} __sigset_t;
which is much bigger than expected by the __sigprocmask system call,
which has
typedef struct {
unsigned long sig[_NSIG_WORDS];
} sigset_t;
For Linux/x86, we can shrink __sigset_t used by __saved_mask in jmp_buf
to add paddings for shadow stack pointer. As long as the new __sigset_t
is not smaller than sigset_t expected by the __sigprocmask system call,
it should work correctly.
This patch adds an internal header file, <setjmpP.h>, to define
__jmp_buf_sigset_t for __saved_mask in jmp_buf for Linux/x86 with a
space to store shadow stack pointer. It verifies __jmp_buf_sigset_t has
the suitable size for the __sigprocmask system call. A run-time test,
tst-saved_mask-1.c, is added to verify that size of __jmp_buf_sigset_t
is sufficient. If its size is too small, the test fails with
rt_sigprocmask(SIG_SETMASK, strace: umoven: short read (4 < 8) @0x7fa8aa28effc
0x7fa8aa28effc, NULL, 8) = -1 EFAULT (Bad address)
rt_sigprocmask(SIG_SETMASK, strace: umoven: short read (4 < 8) @0x7fa8aa28effc
0x7fa8aa28effc, NULL, 8) = -1 EFAULT (Bad address)
rt_sigprocmask(SIG_SETMASK, NULL, 0x7fa8aa28effc, 8) = -1 EFAULT (Bad address)
exit_group(1) = ?
Tested with build-many-glibcs.py.
* debug/longjmp_chk.c: Include <setjmpP.h> instead of
<setjmp.h>.
* setjmp/longjmp.c: Include <setjmpP.h> instead of <setjmp.h>.
(__libc_siglongjmp): Cast &env[0].__saved_mask to "sigset_t *".
* setjmp/sigjmp.c: Include <setjmpP.h> instead of <setjmp.h>.
(__sigjmp_save): Cast &env[0].__saved_mask to "sigset_t *".
* sysdeps/generic/setjmpP.h: New file.
* sysdeps/unix/sysv/linux/x86/jmp_buf-ssp.sym: Likewise.
* sysdeps/unix/sysv/linux/x86/setjmpP.h: Likewise.
* sysdeps/unix/sysv/linux/x86/tst-saved_mask-1.c: Likewise.
* sysdeps/unix/sysv/linux/x86/Makefile (gen-as-const-headers):
Add jmp_buf-ssp.sym.
(tests): Add tst-saved_mask-1.
Continuing the preparation for additional _FloatN / _FloatNx function
aliases, this patch makes s390 libm function implementations use
libm_alias_double to define function aliases. This allows
sysdeps/unix/sysv/linux/s390/fpu/s_fma.c to be removed, as
libm_alias_double handles symbol versioning for long double compat
symbols.
Tested with build-many-glibcs.py for s390-linux-gnu and
s390x-linux-gnu that installed stripped shared libraries are unchanged
by the patch.
* sysdeps/s390/fpu/s_fma.c: Include <libm-alias-double.h>.
[!__fma] (fma): Define using libm_alias_double.
* sysdeps/unix/sysv/linux/s390/fpu/s_fma.c: Remove.
This patch continues filling out TS 18661-3 support by adding *f64x
function aliases on platforms with _Float64x support. (It so happens
the set of such platforms is exactly the same as the set of platforms
with _Float128 support, although on x86_64, x86 and ia32 the _Float64x
format is Intel extended rather than binary128.) The API provided
corresponds exactly to that provided for _Float128, mostly coming from
TS 18661-3. As these functions always alias those for another type
(long double, _Float128 or both), __* function names are not provided,
as in other cases of alias types.
Given the preparation done in previous patches, this one just enables
the feature via Makeconfig and bits/floatn.h, adds symbol versions,
and updates documentation and ABI baselines. The symbol versions are
present unconditionally as GLIBC_2.27 in the relevant Versions files,
as it's OK for those to specify versions for functions that may not be
present in some configurations; no additional complexity is needed
unless in future some configuration gains support for this type that
didn't have such support in 2.27. The Makeconfig additions for ia64
and x86 aren't strictly needed, as those configurations also get
float64x-alias-fcts definitions from
sysdeps/ieee754/float128/Makeconfig, but still seem appropriate given
that _Float64x is not _Float128 for those configurations.
A libm-test-ulps update for x86 is included. This is because
bits/mathinline.h does not have _Float64x support added and for two
functions the use of out-of-line functions results in increased ulps
(ifloat64x shares ulps with ildouble / ifloat128 as appropriate).
Given that we'd like generally to eliminate bits/mathinline.h
optimizations, preferring to have such optimizations in GCC instead,
it seems reasonable not to add such support there for new types. GCC
support for _FloatN / _FloatNx built-in functions is limited, but has
been improved in GCC 8, and at some point I hope the full set of libm
built-in functions in GCC, and other optimizations with
per-floating-type aspects, will be enabled for all _FloatN / _FloatNx
types.
Tested for x86_64 and x86, and with build-many-glibcs.py, with both
GCC 6 and GCC 7.
* sysdeps/ia64/Makeconfig (float64x-alias-fcts): New variable.
* sysdeps/ieee754/float128/Makeconfig (float64x-alias-fcts):
Likewise.
* sysdeps/ieee754/ldbl-128/Makeconfig (float64x-alias-fcts):
Likewise.
* sysdeps/x86/Makeconfig: New file.
* bits/floatn-common.h (__HAVE_FLOAT64X): Remove macro.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* bits/floatn.h (__HAVE_FLOAT64X): New macro.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* sysdeps/ia64/bits/floatn.h (__HAVE_FLOAT64X): Likewise.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* sysdeps/ieee754/ldbl-128/bits/floatn.h (__HAVE_FLOAT64X):
Likewise.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* sysdeps/mips/ieee754/bits/floatn.h (__HAVE_FLOAT64X): Likewise.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* sysdeps/powerpc/bits/floatn.h (__HAVE_FLOAT64X): Likewise.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* sysdeps/x86/bits/floatn.h (__HAVE_FLOAT64X): Likewise.
(__HAVE_FLOAT64X_LONG_DOUBLE): Likewise.
* manual/math.texi (Mathematics): Document support for _Float64x.
* math/Versions (GLIBC_2.27): Add _Float64x functions.
* stdlib/Versions (GLIBC_2.27): Likewise.
* wcsmbs/Versions (GLIBC_2.27): Likewise.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist: Update.
* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
* sysdeps/i386/fpu/libm-test-ulps: Likewise.
* sysdeps/i386/i686/fpu/multiarch/libm-test-ulps: Likewise.
This header file enables sharing of portable declarations and
definitions across all Linux architectures, including hppa (which does
not use <bits/mman-linux.h>).
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Since
commit 8b0e795aaa
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Wed Nov 1 11:49:05 2017 -0200
Simplify Linux sig{timed}wait{info} implementations
sigwait can fail with EINTR. Applications do not expect that, and the
error code is not documented in POSIX or the manual pages.
This commit restores the previous behavior by retrying the system call
on EINTR. It also returns the error code, not -1, on the remaing
errors.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The system call is somewhat obscure because it is closely related
to file descriptor sealing. However, it is also the recommended
way to create alias mappings, which is why it has more general use.
No emulation is provided. Except for the name of the
/proc/self/fd links, it would be possible to implement an
approximation using O_TMPFILE and tmpfs, but this does not appear
to be worth the added complexity.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Building glibc with current mainline GCC fails, among other reasons,
because of an error for use of strlen on the nonstring ut_user field.
This patch changes the problem code in getlogin_r to use __strnlen
instead. It also needs to set the trailing NUL byte of the result
explicitly, because of the case where ut_user does not have such a
trailing NUL byte (but the result should always have one).
Tested for x86_64. Also tested that, in conjunction with
<https://sourceware.org/ml/libc-alpha/2017-11/msg00797.html>, it fixes
the build for arm with mainline GCC.
[BZ #22447]
* sysdeps/unix/getlogin_r.c (__getlogin_r): Use __strnlen not
strlen to compute length of ut_user and set trailing NUL byte of
result explicitly.
This patch updates the hppa bits/mman.h based on Linux 4.14. Some
MADV_* macros are removed in Linux 4.14 as unused/unimplemented, so
this patch removes them from glibc, while adding two new macros added
in Linux 4.14.
Tested (compilation only) for hppa with build-many-glibcs.py.
* sysdeps/unix/sysv/linux/hppa/bits/mman.h
[__USE_MISC] (MADV_SPACEAVAIL): Remove macro.
[__USE_MISC] (MADV_VPS_PURGE): Likewise.
[__USE_MISC] (MADV_VPS_INHERIT): Likewise.
[__USE_MISC] (MADV_HWPOISON): New macro.
[__USE_MISC] (MADV_SOFT_OFFLINE): Likewise.
GDB failed to detect the outermost frame while showing the backtrace
within a thread:
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
Before this patch, the start routines like thread_start had no cfi information.
GDB is then using the prologue unwinder if no cfi information is available.
This unwinder tries to unwind r15 and stops e.g. if r15 was updated or
on some jump-instructions.
On older glibc-versions (before commit "Remove cached PID/TID in clone"
c579f48edb), the thread_start function used
such a jump-instruction and GDB did not fail with an error.
This patch adds cfi information for _start, thread_start and __makecontext_ret
and marks r14 as undefined which marks the frame as outermost frame and GDB
stops the backtrace. Also tested different gcc versions in order to test
_Unwind_Backtrace() in libgcc as this is used by backtrace() in glibc.
ChangeLog:
* sysdeps/s390/s390-64/start.S (_start): Add cfi information for r14.
* sysdeps/s390/s390-32/start.S: (_start): Likewise
* sysdeps/unix/sysv/linux/s390/s390-64/clone.S
(thread_start): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/clone.S
(thread_start): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/__makecontext_ret.S
(__makecontext_ret): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/__makecontext_ret.S
(__makecontext_ret): Likewise.
This patch adds the HWCAP_DCPOP macro from Linux 4.14 to the AArch64
bits/hwcap.h.
Tested (compilation only) for aarch64 with build-many-glibcs.py.
* sysdeps/unix/sysv/linux/aarch64/bits/hwcap.h (HWCAP_DCPOP): New
macro.
This patch adds ARPHRD_RAWIP from Linux 4.14 to the Linux
net/if_arp.h.
Tested for x86_64.
* sysdeps/unix/sysv/linux/net/if_arp.h (ARPHRD_RAWIP): New macro.
Linux 4.14 does not add any new syscalls; this patch updates the
version number in syscall-names.list to reflect that it's still
current for 4.14.
Tested for x86_64 (compilation with build-many-glibcs.py, using Linux
4.14).
* sysdeps/unix/sysv/linux/syscall-names.list: Update kernel
version to 4.14.
of the strncat and strncpy function that may result in truncating
the copied string before the terminating NUL. To avoid false positive
warnings for correct code that intentionally creates sequences of
characters that aren't guaranteed to be NUL-terminated, arrays that
are intended to store such sequences should be decorated with a new
nonstring attribute. This change add this attribute to Glibc and
uses it to suppress such false positives.
ChangeLog:
* misc/sys/cdefs.h (__attribute_nonstring__): New macro.
* sysdeps/gnu/bits/utmp.h (struct utmp): Use it.
* sysdeps/unix/sysv/linux/s390/bits/utmp.h (struct utmp): Same.
Add a new tst-ttyname test that includes several named sub-testcases.
This patch is ordered after the patches with the fixes that it tests for (to
avoid breaking `git bisect`), but for reference, here's how each relevant change
so far affected the testcases in this commit, starting with
15e9a4f378:
| | before | | make checks | don't |
| | 15e9a4f | 15e9a4f | consistent | bail |
|---------------------------------+---------+---------+-------------+-------|
| basic smoketest | PASS | PASS | PASS | PASS |
| no conflict, no match | PASS[1] | PASS | PASS | PASS |
| no conflict, console | PASS | FAIL! | FAIL | PASS! |
| conflict, no match | FAIL | PASS! | PASS | PASS |
| conflict, console | FAIL | FAIL | FAIL | PASS! |
| with readlink target | PASS | PASS | PASS | PASS |
| with readlink trap; fallback | FAIL | FAIL | FAIL | PASS! |
| with readlink trap; no fallback | FAIL | PASS! | PASS | PASS |
| with search-path trap | FAIL | FAIL | PASS! | PASS |
|---------------------------------+---------+---------+-------------+-------|
| | 4/9 | 5/9 | 6/9 | 9/9 |
[1]: 15e9a4f introduced a semantic that, under certain failure
conditions, ttyname sets errno=ENODEV, where previously it didn't
set errno; it's not quite fair to hold "before 15e9a4f" ttyname to
those new semantics. This testcase actually fails, but would have
passed if we tested for the old the semantics.
Each of the failing tests before 15e9a4f are all essentially the same bug: that
it returns a PTY slave with the correct minor device number, but from the wrong
devpts filesystem instance.
15e9a4f sought to fix this, but missed several of the cases that can cause this
to happen, and also broke the case where both the erroneous PTY and the correct
PTY exist.
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Commit 15e9a4f378 introduced logic for ttyname()
sending back ENODEV to signal that we can't get a name for the TTY because we
inherited it from a different mount namespace.
However, just because we inherited it from a different mount namespace and it
isn't available at its original path, doesn't mean that its name is unknowable;
we can still try to find it by allowing the normal fall back on iterating
through devices.
An example scenario where this happens is with "/dev/console" in containers.
It's a common practice among container managers to allocate a PTY master/slave
pair in the host's mount namespace (the slave having a path like "/dev/pty/$X"),
bind mount the slave to "/dev/console" in the container's mount namespace, and
send the slave FD to a process in the container. Inside of the
container, the slave-end isn't available at its original path ("/dev/pts/$X"),
since the container mount namespace has a separate devpts instance from the host
(that path may or may not exist in the container; if it does exist, it's not the
same PTY slave device). Currently ttyname{_r} sees that the file at the
original "/dev/pts/$X" path doesn't match the FD passed to it, and fails early
and gives up, even though if it kept searching it would find the TTY at
"/dev/console". Fix that; don't have the ENODEV path force an early return
inhibiting the fall-back search.
This change is based on the previous patch that adds use of is_mytty in
getttyname and getttyname_r. Without that change, this effectively reverts
15e9a4f, which made us disregard the false similarity of file pointed to by
"/proc/self/fd/$Y", because if it doesn't bail prematurely then that file
("/dev/pts/$X") will just come up again anyway in the fall-back search.
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
In the ttyname and ttyname_r routines on Linux, at several points it needs to
check if a given TTY is the TTY we are looking for. It used to be that this
check was (to see if `maybe` is `mytty`):
__xstat64(_STAT_VER, maybe_filename, &maybe) == 0
#ifdef _STATBUF_ST_RDEV
&& S_ISCHR(maybe.st_mode) && maybe.st_rdev == mytty.st_rdev
#else
&& maybe.st_ino == mytty.st_ino && maybe.st_dev == mytty.st_dev
#endif
This check appears in several places.
Then, one of the changes made in commit 15e9a4f378
was to change that check to:
__xstat64(_STAT_VER, maybe_filename, &maybe) == 0
#ifdef _STATBUF_ST_RDEV
&& S_ISCHR(maybe.st_mode) && maybe.st_rdev == mytty.st_rdev
#endif
&& maybe.st_ino == mytty.st_ino && maybe.st_dev == mytty.st_dev
That is, it made the st_ino and st_dev parts of the check happen even if we have
the st_rdev member. This is an important change, because the kernel allows
multiple devpts filesystem instances to be created; a device file in one devpts
instance may share the same st_rdev with a file in another devpts instance, but
they aren't the same file.
This check appears twice in each file (ttyname.c and ttyname_r.c), once (in
ttyname and __ttyname_r) to check if a candidate file found by inspecting /proc
is the desired TTY, and once (in getttyname and getttyname_r) to check if a
candidate file found by searching /dev is the desired TTY. However, 15e9a4f
only updated the checks for files found via /proc; but the concern about
collisions between devpts instances is just as valid for files found via /dev.
So, update all 4 occurrences the check to be consistent with the version of the
check introduced in 15e9a4f. Make it easy to keep all 4 occurrences of the
check consistent by pulling it in to a static inline function, is_mytty.
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
is_pty returning a bool is fine since there's no possible outcome other than
true or false, and bool is used throughout the codebase.
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Linux 4.10 moved many of the documentation files around.
4.10 came out between the time the patch adding the comment (commit
15e9a4f378) was submitted and the time
it was applied (in February, January, and March 2017; respectively).
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
This patch adds the new MSG_ZEROCOPY constant from Linux 4.14 to the
Linux bits/socket.h.
Tested for x86_64.
* sysdeps/unix/sysv/linux/bits/socket.h (MSG_ZEROCOPY): New enum
constant and macro.
This patch adds the new MADV_WIPEONFORK and MADV_KEEPONFORK from Linux
4.14 to bits/mman-linux.h (and bits/mman.h in the hppa case). Note
there are further hppa MADV_* changes in 4.14; I plan a separate glibc
patch for those.
Tested for x86_64.
* sysdeps/unix/sysv/linux/bits/mman-linux.h
[__USE_MISC] (MADV_WIPEONFORK): New macro.
[__USE_MISC] (MADV_KEEPONFORK): Likewise.
* sysdeps/unix/sysv/linux/hppa/bits/mman.h
[__USE_MISC] (MADV_WIPEONFORK): Likewise.
[__USE_MISC] (MADV_KEEPONFORK): Likewise.
The epoll_wait wrapper uses the raw syscall if __NR_epoll_wait is defined,
and falls back to calling epoll_pwait(..., NULL) if it isn't defined.
However, it didn't include the appropriate headers for __NR_epoll_wait to
be defined, so it was *always* falling back to calling epoll_pwait!
This mistake was introduced in b62c381591,
when epoll_wait changed from being in syscalls.list to always having a C
wrapper.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Verify that sizes, alignments and field offsets of jmp_buf as well as
sigjmp_buf are unchanged regardless how struct __jmp_buf_tag is defined.
Since jmp_buf is target specific, jmp_buf-macros.h is added for each
Linux target. A new target must provides its own jmp_buf-macros.h.
TODO: Hurd needs to provide a jmp_buf-macros.h.
Tested with build-many-glibcs.py.
* include/setjmp.h [!_ISOMAC]: Include <stddef.h> and
<jmp_buf-macros.h>.
[!_ISOMAC] (STR_HELPER): New.
[!_ISOMAC] (STR): Likewise.
[!_ISOMAC] (TEST_SIZE): Likewise.
[!_ISOMAC] (TEST_ALIGN): Likewise.
[!_ISOMAC] (TEST_OFFSET): Likewise.
[!_ISOMAC] Add _Static_assert to check sizes, alignments and
field offsets of jmp_buf as well as sigjmp_buf.
* sysdeps/unix/sysv/linux/aarch64/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/alpha/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/arm/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/hppa/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/i386/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/ia64/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/m68k/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/microblaze/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/jmp_buf-macros.h:
Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/jmp_buf-macros.h:
Likewise.
* sysdeps/unix/sysv/linux/nios2/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/jmp_buf-macros.h:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/jmp_buf-macros.h:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/sh/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/jmp_buf-macros.h:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/jmp_buf-macros.h:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilepro/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/jmp_buf-macros.h: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/jmp_buf-macros.h: Likewise.
This patch simplify Linux sigqueue implementation by assuming
__NR_rt_sigqueueinfo existence due minimum kernel requirement
(it pre-dates Linux git inclusion for Linux 2.6.12).
Checked on x86_64-linux-gnu.
* sysdeps/unix/sysv/linux/sigqueue.c (__sigqueue): Asssume
__NR_rt_sigqueueinfo.
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Zack Weinberg <zackw@panix.com>
This patch simplifies sig{timed}wait{info} by:
- Assuming __NR_rt_sigtimedwait existence on all architectures due minimum
kernel version requirement (it pre-dates Linux git inclusion for Linux
2.6.12).
- Call __sigtimedwait on both sigwait and sigwaitinfo.
- Now that sigwait is based on an internal sigtimedwait call and it is
present of both libc.so and libpthread.so we need to add an external
private definition of __sigtimedwait for libpthread.so call.
Checked on x86_64-linux-gnu.
* sysdeps/unix/sysv/linux/Versions (libc) [GLIBC_PRIVATE]: Add
__sigtimedwait.
* sysdeps/unix/sysv/linux/sigtimedwait.c: Simplify includes and
assume __NR_rt_sigtimedwait.
* sysdeps/unix/sysv/linux/sigwait.c (__sigwait): Call __sigtimedwait
and add LIBC_CANCEL_HANDLED for cancellation marking.
* sysdeps/unix/sysv/linux/sigwaitinfo.c (__sigwaitinfo): Likewise.
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Zack Weinberg <zackw@panix.com>
Using the cache hierarchy linesize minimum in CTR_EL0.
See the comment within the code for rationale.
* sysdeps/unix/sysv/linux/aarch64/sysconf.c: New file.
sigprocmask.c, sigtimedwait.c, sigwait.c and sigwaitinfo.c files from
sysdeps/unix/sysv/linux include nptl-signals.h via nptl/pthreadP.h,
and so SIGCANCEL and SIGSETXID become defined unconditionally. But
later in the code, there are some checks weither symbols defined,
which is useless. This patch removes useless checks.
Checked on x86_64-linux-gnu.
* sysdeps/unix/sysv/linux/sigprocmask.c: Remove useless #ifdefs.
* sysdeps/unix/sysv/linux/sigtimedwait.c: Likewise.
* sysdeps/unix/sysv/linux/sigwait.c: Likewise.
* sysdeps/unix/sysv/linux/sigwaitinfo.c: Likewise.
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Reviewed-by: Andreas Schwab <schwab@suse.de>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
ia64, s390-64, sparc64 and x86_64 host their own implementation of
sigpending() in corresponding files, but they are identical to generic
linux file despite few comments. This patch removes that files, so the
implementation of sigpending() is taken from sysdeps/unix/sysv/linux
for all ports.
Build-tested on x86_64.
* sysdeps/unix/sysv/linux/ia64/sigpending.c: Remove file.
* sysdeps/unix/sysv/linux/s390/s390-64/sigpending.c: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/sigpending.c: Likewise.
* sysdeps/unix/sysv/linux/x86_64/sigpending.c: Likewise.
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
As shown in some buildbot issues on aarch64 and powerpc, calling
clone (VFORK) and waitpid (WNOHANG) does not guarantee the child
is ready to be collected. This patch changes the call back to 0
as before fe05e1cb6d fix.
This change can lead to the scenario 4.3 described in the commit,
where the waitpid call can hang undefinitely on the call. However
this is also a very unlikely and also undefinied situation where
both the caller is trying to terminate a pid before posix_spawn
returns and the race pid reuse is triggered. I don't see how to
correct handle this specific situation within posix_spawn.
Checked on x86_64-linux-gnu, aarch64-linux-gnu and
powerpc64-linux-gnu.
* sysdeps/unix/sysv/linux/spawni.c (__spawnix): Use 0 instead of
WNOHANG in waitpid call.
As noted by Florian Weimer, current Linux posix_spawn implementation
can trigger an assert if the auxiliary process is terminated before
actually setting the err member:
340 /* Child must set args.err to something non-negative - we rely on
341 the parent and child sharing VM. */
342 args.err = -1;
[...]
362 new_pid = CLONE (__spawni_child, STACK (stack, stack_size), stack_size,
363 CLONE_VM | CLONE_VFORK | SIGCHLD, &args);
364
365 if (new_pid > 0)
366 {
367 ec = args.err;
368 assert (ec >= 0);
Another possible issue is killing the child between setting the err and
actually calling execve. In this case the process will not ran, but
posix_spawn also will not report any error:
269
270 args->err = 0;
271 args->exec (args->file, args->argv, args->envp);
As suggested by Andreas Schwab, this patch removes the faulty assert
and also handles any signal that happens before fork and execve as the
spawn was successful (and thus relaying the handling to the caller to
figure this out). Different than Florian, I can not see why using
atomics to set err would help here, essentially the code runs
sequentially (due CLONE_VFORK) and I think it would not be legal the
compiler evaluate ec without checking for new_pid result (thus there
is no need to compiler barrier).
Summarizing the possible scenarios on posix_spawn execution, we
have:
1. For default case with a success execution, args.err will be 0, pid
will not be collected and it will be reported to caller.
2. For default failure case, args.err will be positive and the it will
be collected by the waitpid. An error will be reported to the
caller.
3. For the unlikely case where the process was terminated and not
collected by a caller signal handler, it will be reported as succeful
execution and not be collected by posix_spawn (since args.err will
be 0). The caller will need to actually handle this case.
4. For the unlikely case where the process was terminated and collected
by caller we have 3 other possible scenarios:
4.1. The auxiliary process was terminated with args.err equal to 0:
it will handled as 1. (so it does not matter if we hit the pid
reuse race since we won't possible collect an unexpected
process).
4.2. The auxiliary process was terminated after execve (due a failure
in calling it) and before setting args.err to -1: it will also
be handle as 1. but with the issue of not be able to report the
caller a possible execve failures.
4.3. The auxiliary process was terminated after args.err is set to -1:
this is the case where it will be possible to hit the pid reuse
case where we will need to collected the auxiliary pid but we
can not be sure if it will be expected one. I think for this
case we need to actually change waitpid to use WNOHANG to avoid
hanging indefinitely on the call and report an error to caller
since we can't differentiate between a default failure as 2.
and a possible pid reuse race issue.
Checked on x86_64-linux-gnu.
* sysdeps/unix/sysv/linux/spawni.c (__spawnix): Handle the case where
the auxiliary process is terminated by a signal before calling _exit
or execve.
After commit 37f802f864 (Remove
__need_IOV_MAX and __need_FOPEN_MAX), UIO_MAXIOV is no longer supplied
(indirectly) through <bits/stdio_lim.h>, so sysdeps/posix/sysconf.c no
longer sees the definition.
This patch adds support for *f128 function aliases on platforms where
long double has the binary128 format (and thus GCC 7 provides the
_Float128 type with the same ABI as long double but as a distinct type
in terms of C type compatibility). This is the same API as provided
in glibc 2.26 for powerpc64le / x86_64 / x86 / ia64 where _Float128
has a different format from long double, with the bulk of the API
coming from TS 18661-3. All the functions alias the corresponding
long double functions, and __* function names are not provided since
those are only needed once for each floating-point format, not more
than once for different types with the same format (so for example,
-ffinite-math-only maps foof128 to __fool_finite, while type-generic
macros end up calling e.g. __issignalingl for _Float128 arguments on
such platforms).
The preparation for this feature was done in previous patches, so this
one just needs to add the relevant makefile and header definitions,
and update macro definitions of libm_alias_ldouble_other_r, to turn on
the feature, and update documentation and ABI baselines.
Tested (a) for x86_64, (b) for aarch64, (c) with build-many-glibcs.py
with both GCC 6 and GCC 7.
* sysdeps/ieee754/ldbl-128/Makeconfig: New file.
* sysdeps/ieee754/ldbl-128/bits/floatn.h: Likewise.
* sysdeps/ieee754/ldbl-128/float128-abi.h: Likewise.
* sysdeps/generic/libm-alias-ldouble.h: Include <bits/floatn.h>.
[__HAVE_FLOAT128 && !__HAVE_DISTINCT_FLOAT128]
(libm_alias_ldouble_other_r): Also create _Float128 alias.
* sysdeps/ieee754/ldbl-opt/libm-alias-ldouble.h: Include
<bits/floatn.h>.
[__HAVE_FLOAT128 && !__HAVE_DISTINCT_FLOAT128]
(libm_alias_ldouble_other_r): Also create _Float128 alias.
* manual/math.texi (Mathematics): Document additional architecture
support for _Float128.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist: Update.
* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
Current GLIBC has two ways to implement the single thread optimization
on syscalls to avoid calling the cancellation path: either by using
global variables (__{libc,pthread}_multiple_thread) or by accessing
the TCB field (defined by TLS_MULTIPLE_THREADS_IN_TCB). Both the
variables and the macros to acces its value are defined in the
architecture sysdep-cancel.h header.
This patch consolidates its definition on only one header,
sysdeps/unix/sysv/linux/sysdep-cancel.h, and adds a new define
(SINGLE_THREAD_BY_GLOBAL) which the architecture defines if it prefer
to use the global variables instead of the TCB field. This is an
optimization, so if the architecture does not define it, the TCB
method will be used as default.
Checked on x86_64-linux-gnu and on a build with major touched
ABIs (aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabihf,
hppa-linux-gnu, i686-linux-gnu, m68k-linux-gnu, microblaze-linux-gnu,
mips-linux-gnu, mips64-linux-gnu, powerpc-linux-gnu,
powerpc64le-linux-gnu, s390-linux-gnu, s390x-linux-gnu, sh4-linux-gnu,
sparcv9-linux-gnu, sparc64-linux-gnu, tilegx-linux-gnu).
* sysdeps/unix/sysv/linux/aarch64/sysdep-cancel.h: Remove file.
* sysdeps/unix/sysv/linux/alpha/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/arm/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/hppa/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/mips/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/nios2/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/powerpc/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/sh/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/sparc/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/tile/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/x86_64/sysdep-cancel.h: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/sysdep.h
(SINGLE_THREAD_BY_GLOBAL): Define.
* sysdeps/unix/sysv/linux/aarch64/sysdep.h (SINGLE_THREAD_BY_GLOBAL):
Likewise.
* sysdeps/unix/sysv/linux/alpha/sysdep.h (SINGLE_THREAD_BY_GLOBAL):
Likewise.
* sysdeps/unix/sysv/linux/arm/sysdep.h (SINGLE_THREAD_BY_GLOBAL):
Likewise.
* sysdeps/unix/sysv/linux/hppa/sysdep.h (SINGLE_THREAD_BY_GLOBAL):
Likewise.
* sysdeps/unix/sysv/linux/microblaze/sysdep.h
(SINGLE_THREAD_BY_GLOBAL): Likewise.
* sysdeps/unix/sysv/linux/x86_64/sysdep.h (SINGLE_THREAD_BY_GLOBAL):
Likewise.
glibc has an add-ons mechanism to allow additional software to be
integrated into the glibc build. Such add-ons may be within the glibc
source tree, or outside it at a path passed to the --enable-add-ons
configure option.
localedata and crypt were once add-ons, distributed in separate
release tarballs, but long since stopped using that mechanism.
Linuxthreads was always an add-on. Ports spent some time as an add-on
with separate release tarballs, then was first moved into the glibc
source tree, then had its sysdeps files moved into the main sysdeps
hierarchy so the add-ons mechanism was no longer used. NPTL spent
some time as an add-on in the main glibc tree before stopping using
the add-on mechanism. libidn used to have separate release tarballs
but no longer does so, but still uses the add-ons mechanism within the
glibc source tree. Various other software has supported building with
the add-ons mechanism at times in the past, but I don't think any is
still widely used.
Add-ons involve significant, little-used complexity in the glibc build
system, and make it hard to understand what the space of possible
glibc configurations is. This patch removes the add-ons mechanism.
libidn is now built via the Subdirs mechanism to cause any
configuration using sysdeps/unix/inet to build libidn; HAVE_LIBIDN
(which effectively means shared libraries are available) is now
defined via sysdeps/unix/inet/configure. Various references to
add-ons around the source tree are removed (in the case of maint.texi,
the example list of sysdeps directories is still very out of date).
Externally maintained ports should now put their files in the normal
sysdeps directory structure rather than being arranged as add-ons;
they probably need to change e.g. elf.h anyway, rather than actually
being able to work just as a drop-in subtree. Hurd libpthread should
be arranged similarly to NPTL, so some files might go in a
hurd-pthreads (or similar) top-level directory in glibc, while sysdeps
files should go in the normal sysdeps directory structure (possibly in
hurd or hurd-pthreads subdirectories, just as there are nptl
subdirectories in the sysdeps tree).
Tested for x86_64, and with build-many-glibcs.py.
* configure.ac (--enable-add-ons): Remove option.
(machine): Do not mention add-ons in comment.
(LIBC_PRECONFIGURE): Likewise.
(add_ons): Remove variable and sanity checks and logic to locate
add-ons.
(add_ons_automatic): Remove variable.
(configured_add_ons): Likewise.
(add_ons_sfx): Likewise.
(add_ons_pfx): Likewise.
(add_on_subdirs): Likewise.
(sysnames_add_ons): Likewise. Remove loop over add-ons and
consideration of add-ons in Implies handling.
(sysdeps_add_ons): Likewise.
* configure: Regenerated.
* libidn/configure.ac: Remove.
* libidn/configure: Likewise.
* sysdeps/unix/inet/configure.ac: New file.
* sysdeps/unix/inet/configure: New generated file.
* sysdeps/unix/inet/Subdirs: Add libidn.
* Makeconfig (sysdeps-srcdirs): Remove variable.
(+sysdep_dirs): Do not include $(sysdeps-srcdirs).
($(common-objpfx)config.status): Do not depend on add-on files.
($(common-objpfx)shlib-versions.v.i): Do not mention add-ons in
comment.
(all-subdirs): Do not include $(add-on-subdirs).
* Makefile (dist-prepare): Do not use $(sysdeps-add-ons).
* config.make.in (add-ons): Remove variable.
(add-on-subdirs): Likewise.
(sysdeps-add-ons): Likewise.
* manual/Makefile (add-chapters): Remove.
($(objpfx)texis): Do not depend on $(add-chapters).
(nonexamples): Do not handle $(add-chapters).
(examples): Do not handle $(add-ons).
(chapters.% top-menu.%): Do not pass '$(add-chapters)' to
libc-texinfo.sh.
* manual/install.texi (Installation): Do not mention add-ons.
(--enable-add-ons): Do not document configure option.
* INSTALL: Regenerated.
* manual/libc-texinfo.sh: Do not handle $2 add-ons argument.
* manual/maint.texi (Hierarchy Conventions): Do not mention
add-ons.
* scripts/build-many-glibcs.py (Glibc.build_glibc): Do not use
--enable-add-ons.
* scripts/gen-sorted.awk: Do not handle Subdirs files from
add-ons.
* scripts/test-installation.pl: Do not handle glibc-compat add-on.
* sysdeps/nptl/Makeconfig: Do not mention add-ons in comment.
32-bit SPARC libm should have compat symbols for copysignl
(GLIBC_2.0), fabsl (GLIBC_2.0), fmal (GLIBC_2.1), pointing to the
double functions; they were present in glibc 2.8, for example, but are
now missing, probably when optimized SPARC function implementations
were added without appropriate compat symbol handling. The same
applies to copysignl in libc. This patch restores those compat
symbols.
Tested with build-many-glibcs.py for sparcv9-linux-gnu.
[BZ #22229]
* sysdeps/sparc/sparc32/fpu/s_copysign.S: Include
<math_ldbl_opt.h>
(copysignl): Define as compat symbol at version GLIBC_2_0 for libm
and libc.
* sysdeps/sparc/sparc32/fpu/s_fabs.S: Include <math_ldbl_opt.h>.
(fabsl): Define as compat symbol at version GLIBC_2_0 for libm.
* sysdeps/sparc/sparc32/fpu/s_fma.c: Include <math_ldbl_opt.h>.
(fmal): Define as compat symbol at version GLIBC_2_1 for libm.
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_copysign.S:
Include <math_ldbl_opt.h>
(copysignl): Define as compat symbol at version GLIBC_2_0 for libm
and libc.
(compat_symbol): Undefine and redefine.
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fabs.S: Include
<math_ldbl_opt.h>
(fabsl): Define as compat symbol at version GLIBC_2_0 for libm.
(compat_symbol): Undefine and redefine.
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fma.c
[HAVE_AS_VIS3_SUPPORT]: Include <math_ldbl_opt.h>.
[HAVE_AS_VIS3_SUPPORT] (fmal): Define as compat symbol at version
GLIBC_2_1 for libm.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Add
GLIBC_2.0 copysignl symbol.
* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Add
GLIBC_2.0 copysignl and fabsl and GLIBC_2.1 fmal symbols.
For static PIE code, PIC is defined and SHARED is undefined. We
should check SHARED instead PIC for SYSCALL_ERROR_NAME.
* sysdeps/unix/sysv/linux/tile/sysdep.h (SYSCALL_ERROR_NAME):
Check SHARED instead PIC.
Hide internal fadvise64/fallocate64 functions to allow direct access
within libc.so and libc.a without using GOT nor PLT.
[BZ #18822]
* sysdeps/unix/sysv/linux/posix_fadvise64.c
(__posix_fadvise64_l64): Add Add libc_hidden_proto and
libc_hidden_def.
* sysdeps/unix/sysv/linux/posix_fallocate64.c
(__posix_fallocate64_l64): Likewise.
Hide internal __sched_setaffinity_new function to allow direct access
within libc.so and libc.a without using GOT nor PLT.
[BZ #18822]
* sysdeps/unix/sysv/linux/sched_setaffinity.c
(__sched_setaffinity_new): Add libc_hidden_proto and
libc_hidden_def.
Hide internal __glob64 function to allow direct access within libc.so
and libc.a without using GOT nor PLT.
[BZ #18822]
* include/glob.h (__glob64): Add libc_hidden_proto.
* sysdeps/unix/sysv/linux/glob64.c (__glob64): Add
libc_hidden_def.
Hide internal __new_getrlimit function to allow direct access within
libc.so and libc.a without using GOT nor PLT.
[BZ #18822]
* sysdeps/unix/sysv/linux/getrlimit64.c (__new_getrlimit): Add
attribute_hidden.
Hide internal __tcgetattr function to allow direct access within libc.so
and libc.a without using GOT nor PLT.
[BZ #18822]
* include/termios.h (__tcgetattr): Add libc_hidden_proto.
* sysdeps/unix/bsd/tcgetattr.c (__tcgetattr): Add
libc_hidden_def.
* sysdeps/unix/sysv/linux/tcgetattr.c (__tcgetattr): Likewise.
* termios/tcgetattr.c (__tcgetattr): Likewise.
