The resolv/res_debug.c function p_secstodate (which is a public
function exported from libresolv, taking an unsigned long argument)
does:
struct tm timebuf;
time = __gmtime_r(&clock, &timebuf);
time->tm_year += 1900;
time->tm_mon += 1;
sprintf(output, "%04d%02d%02d%02d%02d%02d",
time->tm_year, time->tm_mon, time->tm_mday,
time->tm_hour, time->tm_min, time->tm_sec);
If __gmtime_r returns NULL (because the year overflows the range of
int), this will dereference a null pointer. Otherwise, if the
computed year does not fit in four characters, this will cause a
buffer overrun of the fixed-size 15-byte buffer. With current GCC
mainline, there is a compilation failure because of the possible
buffer overrun.
I couldn't find a specification for how this function is meant to
behave, but Paul pointed to RFC 4034 as relevant to the cases where
this function is called from within glibc. The function's interface
is inherently problematic when dates beyond Y2038 might be involved,
because of the ambiguity in how to interpret 32-bit timestamps as such
dates (the RFC suggests interpreting times as being within 68 years of
the present date, which would mean some kind of interface whose
behavior depends on the present date).
This patch works on the basis of making a minimal fix in preparation
for obsoleting the function. The function is made to handle times in
the interval [0, 0x7fffffff] only, on all platforms, with <overflow>
used as the output string in other cases (and errno set to EOVERFLOW
in such cases). This seems to be a reasonable state for the function
to be in when made a compat symbol by a future patch, being compatible
with any existing uses for existing timestamps without trying to work
for later timestamps. Results independent of the range of time_t also
simplify the testcase.
I couldn't persuade GCC to recognize the ranges of the struct tm
fields by adding explicit range checks with a call to
__builtin_unreachable if outside the range (this looks similar to
<https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80776>), so having added
a range check on the input, this patch then disables the
-Wformat-overflow= warning for the sprintf call (I prefer that to the
use of strftime, as being more transparently correct without knowing
what each of %m and %M etc. is).
I do not know why this build failure should be new with mainline GCC
(that is, I don't know what GCC change might have introduced it, when
the basic functionality for such warnings was already in GCC 7).
I do not know if this is a security issue (that is, if there are
plausible ways in which a date before -999 or after 9999 from an
untrusted source might end up in this function). The system clock is
arguably an untrusted source (in that e.g. NTP is insecure), but
probably not to that extent (NTP can't communicate such wild
timestamps), and uses from within glibc are limited to 32-bit inputs.
Tested with build-many-glibcs.py that this restores the build for arm
with yesterday's mainline GCC. Also tested for x86_64 and x86.
[BZ #22463]
* resolv/res_debug.c: Include <libc-diag.h>.
(p_secstodate): Assert time_t at least as wide as u_long. On
overflow, use integer seconds since the epoch as output, or use
"<overflow>" as output and set errno to EOVERFLOW if integer
seconds since the epoch would be 14 or more characters.
(p_secstodate) [__GNUC_PREREQ (7, 0)]: Disable -Wformat-overflow=
for sprintf call.
* resolv/tst-p_secstodate.c: New file.
* resolv/Makefile (tests): Add tst-p_secstodate.
($(objpfx)tst-p_secstodate): Depend on $(objpfx)libresolv.so.
sysdeps/sparc/sparc64/soft-fp has files s_frexpl.c, s_scalblnl.c and
s_scalbnl.c that are never used because the ldbl-128 versions always
come first in the sysdeps directory ordering. This patch removes the
unused files.
Tested with build-many-glibcs.py that installed stripped shared
libraries are unchanged by this patch.
* sysdeps/sparc/sparc64/soft-fp/s_frexpl.c: Remove file.
* sysdeps/sparc/sparc64/soft-fp/s_scalblnl.c: Likewise.
* sysdeps/sparc/sparc64/soft-fp/s_scalbnl.c: Likewise.
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.
[BZ #15537]
* localedata/locales/lv_LV (LC_COLLATE): Fix collation by
using “copy "iso14651_t1"” and then implementing the
collation rules for lv from CLDR on top of that.
* Makefile: Add lv_LV.UTF-8 to test-input and to the list
of locales to be built for testing.
* lv_LV.UTF-8.in: New file with test data to test the Latvian
sorting.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
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.
GCC 4.9 (the minimum current supported) emits an warning for universal
zero initializer ({0}) on ASSERT_PTHREAD_INTERNAL_SIZE:
pthread_attr_init.c: In function ‘__pthread_attr_init_2_1’:
pthread_attr_init.c:37:3: error: missing braces around initializer [-Werror=missing-braces]
ASSERT_PTHREAD_INTERNAL_SIZE (pthread_attr_t, struct pthread_attr);
^
pthread_attr_init.c:37:3: error: (near initialization for ‘(anonymous).__size’) [-Werror=missing-braces]
It is fact GCC BZ#53119 [1] fixed in later version (GCC5+). Since
current branch is closed and there is no indication it will be backports
(comment #20 in same bug report) this patch fixes by using a double
bracket to zero initialize the struct.
Checked on x86_64-linux-gnu with GCC 7 and GCC 4.9.
* nptl/pthreadP.h (ASSERT_PTHREAD_INTERNAL_SIZE): Add workarond for
-Wmissing-braces on GCC 4.9.
[1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53119
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
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.
On s390 (31bit) various debug/tst-*chk* testcases are failing as the tests
are ending with a segmentation fault.
One test is e.g. calling wcsnrtombs in debug/tst-chk1.c:1549.
The function wcsnrtombs itself calls __wcsnlen. This function is called via
PLT! The PLT-stub itself loads the address from GOT (r12 is assumed to be
the GOT-pointer). In this case the loaded address is zero and the following
branch leads to the segmentation fault.
Due to the attribute_hidden in commit 44af8a32c3
"Mark internal wchar functions with attribute_hidden [BZ #18822]"
for e.g. the __wcsnlen function, r12 is not loaded with the GOT-pointer
in wcsnrtombs.
On s390x (64bit), this __wcsnlen call is also using the PLT-stub. But it is
not failing as the GOT-pointer is setup with larl-instruction by the PLT-stub
itself.
Note: On s390x/s390, __wcsnlen is an IFUNC symbol.
On x86_64, __wcsnlen is also an IFUNC symbol and is called via PLT, too.
Further IFUNC symbols on s390 which were marked as hidden by the mentioned
commit are: __wcscat, __wcsncpy, __wcpncpy, __wcschrnul.
This patch removes the attribute_hidden in wchar.h.
Then the compiler setups e.g. r12 on s390 in order to call __wcsnlen via PLT.
ChangeLog:
* include/wchar.h (__wcsnlen, __wcscat, __wcsncpy, __wcpncpy,
__wcschrnul): Remove attribute_hidden.
Numbers for very small sizes (< 128B) are much noisier for non-cached
benchmarks like the walk benchmarks, so don't include them.
* benchtests/bench-memcpy-walk.c (START_SIZE): Set to 128.
* benchtests/bench-memmove-walk.c (START_SIZE): Likewise.
* benchtests/bench-memset-walk.c (START_SIZE): Likewise.
Make the walking benchmarks walk only backwards since copying both
ways is biased in favour of implementations that use non-temporal
stores for larger sizes; falkor is one of them. This also fixes up
bugs in computation of the result which ended up multiplying the
length with the timing result unnecessarily.
* benchtests/bench-memcpy-walk.c (do_one_test): Copy only
backwards. Fix timing computation.
* benchtests/bench-memmove-walk.c (do_one_test): Likewise.
* benchtests/bench-memset-walk.c (do_one_test): Walk backwards
on memset by N at a time. Fix timing computation.
Also remove a comment about performance. fwrite vs writev performance
is a very complex topic and cannot be reduced to a simple advice based
on transfer size.
The requirement to write "deny" to /proc/<pid>/setgroups for a given user
namespace before being able to write a gid mapping was introduced in Linux
3.19. Before that this requirement including the file did not exist.
So don't fail when errno == ENOENT.
System defaults vary, and a mere unshare (CLONE_NEWNS) (which is part of
support_become_root) is no longer sufficient.
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
create_temp_file automatically supplies the test directory and the
XXXXXX suffix. support_create_temp_directory required the caller to
specify them, which was confusing.
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Linux commit ID cba6ac4869e45cc93ac5497024d1d49576e82666 reserved a new
bit for a scenario where transactional memory is available, but the
suspended state is disabled.
* sysdeps/powerpc/bits/hwcap.h (PPC_FEATURE2_HTM_NO_SUSPEND): New
macro.
* sysdeps/powerpc/dl-procinfo.c (_dl_powerpc_cap_flags): Add
htm-no-suspend.
Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>
This patch continues the preparation for additional _FloatN / _FloatNx
function aliases by using libm_alias_ldouble for sysdeps/x86_64/fpu
long double functions, so that they can have _Float64x aliases added
in future.
Tested for x86_64, including build-many-glibcs.py tests that installed
stripped shared libraries are unchanged by the patch.
* sysdeps/x86_64/fpu/e_expl.S: Include <libm-alias-ldouble.h>.
[USE_AS_EXPM1L] (expm1l): Define using libm_alias_ldouble.
* sysdeps/x86_64/fpu/s_ceill.S: Include <libm-alias-ldouble.h>.
(ceill): Define using libm_alias_ldouble.
* sysdeps/x86_64/fpu/s_copysignl.S: Include
<libm-alias-ldouble.h>.
(copysignl): Define using libm_alias_ldouble.
* sysdeps/x86_64/fpu/s_fabsl.S: Include <libm-alias-ldouble.h>.
(fabsl): Define using libm_alias_ldouble.
* sysdeps/x86_64/fpu/s_floorl.S: Include <libm-alias-ldouble.h>.
(floorl): Define using libm_alias_ldouble.
* sysdeps/x86_64/fpu/s_fmaxl.S: Include <libm-alias-ldouble.h>.
(fmaxl): Define using libm_alias_ldouble.
* sysdeps/x86_64/fpu/s_fminl.S: Include <libm-alias-ldouble.h>.
(fminl): Define using libm_alias_ldouble.
* sysdeps/x86_64/fpu/s_llrintl.S: Include <libm-alias-ldouble.h>.
(llrintl): Define using libm_alias_ldouble.
(lrintl): Likewise.
* sysdeps/x86_64/fpu/s_nearbyintl.S: Include
<libm-alias-ldouble.h>.
(nearbyintl): Define using libm_alias_ldouble.
* sysdeps/x86_64/fpu/s_truncl.S: Include <libm-alias-ldouble.h>.
(truncl): Define using libm_alias_ldouble.
* sysdeps/x86_64/x32/fpu/s_lrintl.S: Include
<libm-alias-ldouble.h>.
(lrintl): Define using libm_alias_ldouble.
This patch continues the preparation for additional _FloatN / _FloatNx
function aliases by using libm_alias_ldouble for sysdeps/i386/fpu long
double functions, so that they can have _Float64x aliases added in
future.
Tested for x86_64 (which includes some of these implementations) and
x86, including build-many-glibcs.py tests that installed stripped
shared libraries are unchanged by the patch.
* sysdeps/i386/fpu/e_expl.S: Include <libm-alias-ldouble.h>.
[USE_AS_EXPM1L] (expm1l): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_asinhl.S: Include <libm-alias-ldouble.h>.
(asinhl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_atanl.c: Include <libm-alias-ldouble.h>.
(atanl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_cbrtl.S: Include <libm-alias-ldouble.h>.
(cbrtl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_ceill.S: Include <libm-alias-ldouble.h>.
(ceill): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_copysignl.S: Include <libm-alias-ldouble.h>.
(copysignl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_fabsl.S: Include <libm-alias-ldouble.h>.
(fabsl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_floorl.S: Include <libm-alias-ldouble.h>.
(floorl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_fmaxl.S: Include <libm-alias-ldouble.h>.
(fmaxl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_fminl.S: Include <libm-alias-ldouble.h>.
(fminl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_frexpl.S: Include <libm-alias-ldouble.h>.
(frexpl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_llrintl.S: Include <libm-alias-ldouble.h>.
(llrintl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_logbl.c: Include <libm-alias-ldouble.h>.
(logbl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_lrintl.S: Include <libm-alias-ldouble.h>.
(lrintl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_nearbyintl.S: Include <libm-alias-ldouble.h>.
(nearbyintl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_nextafterl.c: Include <libm-alias-ldouble.h>.
(nextafterl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_remquol.S: Include <libm-alias-ldouble.h>.
(remquol): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_rintl.c: Include <libm-alias-ldouble.h>.
(rintl): Define using libm_alias_ldouble.
* sysdeps/i386/fpu/s_truncl.S: Include <libm-alias-ldouble.h>.
(truncl): Define using libm_alias_ldouble.
* sysdeps/i386/i686/fpu/s_fmaxl.S: Include <libm-alias-ldouble.h>.
(fmaxl): Define using libm_alias_ldouble.
* sysdeps/i386/i686/fpu/s_fminl.S: Include <libm-alias-ldouble.h>.
(fminl): Define using libm_alias_ldouble.
Further _FloatN / _FloatNx type alias support will involve making
architecture-specific .S files use the common macros for libm function
aliases. Making them use those macros will also serve to simplify
existing code for aliases / symbol versions in various cases, similar
to such simplifications for ldbl-opt code.
The libm-alias-*.h files sometimes need to include <bits/floatn.h> to
determine which aliases they should define. At present, this does not
work for inclusion from .S files because <bits/floatn.h> can define
typedefs for old compilers. This patch changes all the
<bits/floatn.h> and <bits/floatn-common.h> headers to include
__ASSEMBLER__ conditionals. Those conditionals disable everything
related to C syntax in the __ASSEMBLER__ case, not just the problem
typedefs, as that seemed cleanest. The __HAVE_* definitions remain in
the __ASSEMBLER__ case, as those provide information that is required
to define the correct set of aliases.
Tested with build-many-glibcs.py for a representative set of
configurations (x86_64-linux-gnu i686-linux-gnu ia64-linux-gnu
powerpc64le-linux-gnu mips64-linux-gnu-n64 sparc64-linux-gnu) with GCC
6. Also tested with GCC 6 for i686-linux-gnu in conjunction with
changes to use alias macros in .S files.
* bits/floatn-common.h [!__ASSEMBLER]: Disable everything related
to C syntax instead of availability and properties of types.
* bits/floatn.h [!__ASSEMBLER]: Likewise.
* sysdeps/ia64/bits/floatn.h [!__ASSEMBLER]: Likewise.
* sysdeps/ieee754/ldbl-128/bits/floatn.h [!__ASSEMBLER]: Likewise.
* sysdeps/mips/ieee754/bits/floatn.h [!__ASSEMBLER]: Likewise.
* sysdeps/powerpc/bits/floatn.h [!__ASSEMBLER]: Likewise.
* sysdeps/x86/bits/floatn.h [!__ASSEMBLER]: Likewise.
Without UID/GID maps, file creation will file with EOVERFLOW.
This patch is based on DJ Delorie's work on container testing.
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
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.
GCC 4.9 and 5 do not generate a correct f{max,min}nm instruction for
__builtin_{fmax,fmin}{f} without -ffinite-math-only. It is clear a
compiler issue since the instruction can handle NaN and Inf correctly
and GCC6+ does not show this issue.
We can backport a fix to GCC 5, raise the minimum required GCC version
for aarch64 (since GCC 4.9 branch is now closed [1]) and/or add
configure check to check for this issue. However I think
-ffinite-math-only should be safe for these specific implementations
and it is a simpler solution.
Checked on aarch64-linux-gnu with GCC 5.3.1.
* sysdeps/aarch64/fpu/Makefile (CFLAGS-s_fmax.c, CFLAGS-s_fmaxf.c,
CFLAGS-s_fmin.c, CFLAGS-s_fminf.c): New rule: add -ffinite-math-only.
[1] https://gcc.gnu.org/ml/gcc/2016-08/msg00010.html
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
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.
Update all sourceware links to https. The website redirects
everything to https anyway so let the web server do a bit less work.
The only reference that remains unchanged is the one in the old
ChangeLog, since it didn't seem worth changing it.
* NEWS: Update sourceware link to https.
* configure.ac: Likewise.
* crypt/md5test-giant.c: Likewise.
* dlfcn/bug-atexit1.c: Likewise.
* dlfcn/bug-atexit2.c: Likewise.
* localedata/README: Likewise.
* malloc/tst-mallocfork.c: Likewise.
* manual/install.texi: Likewise.
* nptl/tst-pthread-getattr.c: Likewise.
* stdio-common/tst-fgets.c: Likewise.
* stdio-common/tst-fwrite.c: Likewise.
* sunrpc/Makefile: Likewise.
* sysdeps/arm/armv7/multiarch/memcpy_impl.S: Likewise.
* wcsmbs/tst-mbrtowc2.c: Likewise.
* configure: Regenerate.
* INSTALL: Regenerate.
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>
Commit 15e9a4f378 introduced ENODEV as a possible
error condition for ttyname and ttyname_r. Update the manual to mention this GNU
extension.
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.
This patch simplifies sighold a bit by removing an extra sigprocmask
and using SIG_BLOCK (which union of the current set and the set argument).
Checked on x86_64-linux-gnu.
* signal/sighold.c (sighold): Optimize implementation.
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch simplify sigpause by remobing the single thread optimization
since it will be handled already by the __sigsuspend call.
Checked on x86_64-linux-gnu.
* sysdeps/posix/sigpause.c (do_sigpause): Remove.
(__sigpause): Rely on __sigsuspend to implement single thread
optimization. Add LIBC_CANCEL_HANDLED for cancellation marking.
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Zack Weinberg <zackw@panix.com>
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>
This commit adds a "subheaps" field to the malloc_info output that
shows the number of heaps that were allocated to extend a non-main
arena.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
