Joseph Myers [Fri, 18 May 2018 11:57:15 +0000 (11:57 +0000)]
Fix year 2039 bug for localtime with 64-bit time_t (bug 22639).
Bug 22639 reports localtime failing to handle time offset transitions
correctly in 2039 and later on platforms with 64-bit time_t.
The problem is the use of SECSPERDAY (constant 86400) in calculations
such as
t = ((year - 1970) * 365
+ /* Compute the number of leapdays between 1970 and YEAR
(exclusive). There is a leapday every 4th year ... */
+ ((year - 1) / 4 - 1970 / 4)
/* ... except every 100th year ... */
- ((year - 1) / 100 - 1970 / 100)
/* ... but still every 400th year. */
+ ((year - 1) / 400 - 1970 / 400)) * SECSPERDAY;
where t is of type time_t and year is of type int. Before my commit 92bd70fb85bce57ac47ba5d8af008736832c955a (an update from tzcode,
included in 2.26 and later releases), SECSPERDAY was obtained from a
file imported from tzcode, where the value included a cast to
int_fast32_t. On 64-bit platforms, glibc defines int_fast32_t to be
long int, so 64-bit, but my patch resulted in it changing to int.
(The bug would probably have existed even before my patch for x32,
which has 64-bit time_t but 32-bit int_fast32_t, but I haven't
verified that.)
This patch fixes the problem by including a cast to time_t in the
definition of SECSPERDAY. (64-bit time support for 32-bit systems
should move such code that isn't a public interface to using the
internal 64-bit version of time_t throughout.)
Tested for x86_64 and x86.
[BZ #22639]
* time/tzset.c (SECSPERDAY): Cast to time_t.
* time/tst-y2039.c: New file.
* time/Makefile (tests): Add tst-y2039.
These comments should make it easier to see the (small) diff introduced
in cf8e3f8757. Without these comments, the diff may get list on a future
upstream merge.
Josh Kunz [Wed, 7 Aug 2019 18:40:50 +0000 (11:40 -0700)]
Make gen-XX-const scripts work with llvm-as
The gen-as-const and gen-py-const scripts are used to generate integer constant
definitions from a list of constant C-expressions. This is achieved by
generating a C program with inline `asm` statements, that depend on
these constant expressions. During compilation, the constant expressions
are evaluated, and included in the inline asm. The build process
generates only the assembly, and then used `sed` to extract the values
from the assembly text.
This is clever. It allows the build process to extract the value of C
statements built under the target architecture. The implementation is a
bit fragile, but it is not immediately obvious to me how it could be
improved.
This change slightly modifies `gen-as-const` and `gen-py-const` to emit
valid assembly directives instead of invalid directives that were
previously emitted. Since the values are extracted via string parsing,
this has no effect on the values extracted. This is needed because the
LLVM assembler validates all statements before emitting them, whereas it
appears GCC will literally emit any `asm` directives without validation
or recognition.
According to ARMv8 architecture reference manual section C7.2.188, SIMD MOV (to
general) instruction format is
MOV <Xd>, <Vn>.D[<index>]
gas appears to accept "<Vn>.2D[<index>]" as well, but clang's assembler does
not. C.f. https://community.arm.com/developer/ip-products/processors/f/cortex-a-forum/5214/aarch64-assembly-syntax-for-armclang
Zack Weinberg [Wed, 7 Feb 2018 20:45:58 +0000 (15:45 -0500)]
[BZ #19239] Don't include sys/sysmacros.h from sys/types.h.
This completes the deprecation and removal of this inclusion, which
was begun in the 2.25 release.
* posix/sys/types.h: Don't include sys/sysmacros.h.
* misc/sys/sysmacros.h: Remove the conditional deprecation
warnings for the macros defined by this header.
Raman Tenneti [Fri, 27 Aug 2021 23:36:05 +0000 (16:36 -0700)]
Changes to compile glibc-2.27 on PPC (Power8) with clang.
+ Use DOT_MACHINE macro instead of ".machine" instruction.
+ Use __isinf and __isinff instead of builtin versions.
+ In s_logb, s_logbf and s_logbl functions, used float versions to
calculate "ret = x & 0x7f800000;" expression.
Paul Pluzhnikov [Sun, 6 May 2018 01:08:27 +0000 (18:08 -0700)]
Fix stack overflow with huge PT_NOTE segment [BZ #20419]
A PT_NOTE in a binary could be arbitratily large, so using alloca
for it may cause stack overflow. If the note is larger than
__MAX_ALLOCA_CUTOFF, use dynamically allocated memory to read it in.
2018-05-05 Paul Pluzhnikov <ppluzhnikov@google.com>
Stefan Liebler [Fri, 4 May 2018 08:00:59 +0000 (10:00 +0200)]
Fix blocking pthread_join. [BZ #23137]
On s390 (31bit) if glibc is build with -Os, pthread_join sometimes
blocks indefinitely. This is e.g. observable with
testcase intl/tst-gettext6.
pthread_join is calling lll_wait_tid(tid), which performs the futex-wait
syscall in a loop as long as tid != 0 (thread is alive).
On s390 (and build with -Os), tid is loaded from memory before
comparing against zero and then the tid is loaded a second time
in order to pass it to the futex-wait-syscall.
If the thread exits in between, then the futex-wait-syscall is
called with the value zero and it waits until a futex-wake occurs.
As the thread is already exited, there won't be a futex-wake.
In lll_wait_tid, the tid is stored to the local variable __tid,
which is then used as argument for the futex-wait-syscall.
But unfortunately the compiler is allowed to reload the value
from memory.
With this patch, the tid is loaded with atomic_load_acquire.
Then the compiler is not allowed to reload the value for __tid from memory.
ChangeLog:
[BZ #23137]
* sysdeps/nptl/lowlevellock.h (lll_wait_tid):
Use atomic_load_acquire to load __tid.
Joseph Myers [Tue, 24 Apr 2018 12:11:35 +0000 (12:11 +0000)]
Add PTRACE_SECCOMP_GET_METADATA from Linux 4.16 to sys/ptrace.h.
This patch adds the PTRACE_SECCOMP_GET_METADATA constant from Linux
4.16 to all relevant sys/ptrace.h files. A type struct
__ptrace_seccomp_metadata, analogous to other such types, is also
added.
manual: Various fixes to the mbstouwcs example, and mbrtowc update
The example did not work because the null byte was not converted, and
mbrtowc was called with a zero-length input string. This results in a
(size_t) -2 return value, so the function always returns NULL.
The size computation for the heap allocation of the result was
incorrect because it did not deal with integer overflow.
Error checking was missing, and the allocated memory was not freed on
error paths. All error returns now set errno. (Note that there is an
assumption that free does not clobber errno.)
The slightly unportable comparision against (size_t) -2 to catch both
(size_t) -1 and (size_t) -2 return values is gone as well.
A null wide character needs to be stored in the result explicitly, to
terminate it.
The description in the manual is updated to deal with these finer
points. The (size_t) -2 behavior (consuming the input bytes) matches
what is specified in ISO C11.
Jesse Hathaway [Tue, 27 Mar 2018 21:17:59 +0000 (21:17 +0000)]
getlogin_r: return early when linux sentinel value is set
When there is no login uid Linux sets /proc/self/loginid to the sentinel
value of, (uid_t) -1. If this is set we can return early and avoid
needlessly looking up the sentinel value in any configured nss
databases.
Checked on aarch64-linux-gnu.
* sysdeps/unix/sysv/linux/getlogin_r.c (__getlogin_r_loginuid): Return
early when linux sentinel value is set.
Joseph Myers [Tue, 20 Mar 2018 18:25:24 +0000 (18:25 +0000)]
Fix signed integer overflow in random_r (bug 17343).
Bug 17343 reports that stdlib/random_r.c has code with undefined
behavior because of signed integer overflow on int32_t. This patch
changes the code so that the possibly overflowing computations use
unsigned arithmetic instead.
Note that the bug report refers to "Most code" in that file. The
places changed in this patch are the only ones I found where I think
such overflow can occur.
Tested for x86_64 and x86.
[BZ #17343]
* stdlib/random_r.c (__random_r): Use unsigned arithmetic for
possibly overflowing computations.
This simple test uses sigaction to define a signal handler. It then
uses sigaction again to fetch the information about the same signal
handler, and check that they are consistent. This is enough to detect
mismatches between struct kernel_sigaction and the kernel version of
struct sigaction, like in BZ #23069.
Changelog:
* signal/tst-sigaction.c: New file to test BZ #23069.
* signal/Makefile (tests): Fix indentation. Add tst-sigaction.
RISC-V: fix struct kernel_sigaction to match the kernel version [BZ #23069]
The RISC-V kernel doesn't define SA_RESTORER, hence the kernel version
of struct sigaction doesn't have the sa_restorer field. The default
kernel_sigaction.h therefore can't be used.
This patch adds a RISC-V specific version of kernel_sigaction.h to fix
the issue. This fixes for example the libnih testsuite.
Note that this patch is not needed in master as the bug has been fixed
by commit b4a5d26d8835 ("linux: Consolidate sigaction implementation").
Rafal Luzynski [Thu, 15 Mar 2018 02:29:07 +0000 (03:29 +0100)]
NEWS: Add entries for bugs: 22848, 22932, 22937, 22963.
Alternative (nominative/genitive) month names have been added to the
Catalan and Czech locale data and the abbreviated alternative names to
Catalan and Greek.
As spotted by GNOME translation team, Greek language has the actually
visible difference between the abbreviated nominative and the abbreviated
genitive case for some month names. Examples:
and more month names with similar differences.
Original discussion: https://bugzilla.gnome.org/show_bug.cgi?id=793645#c21
A GNOME translator asked to use the same abbreviated month names
as provided by CLDR. This sounds reasonable. See the discussion:
https://bugzilla.gnome.org/show_bug.cgi?id=793645#c27
[BZ #22932]
* localedata/locales/lt_LT (abmon): Synchronize with CLDR.
This patch fixes the i386 sa_restorer field initialization for sigaction
syscall for kernel with vDSO. As described in bug report, i386 Linux
(and compat on x86_64) interprets SA_RESTORER clear with nonzero
sa_restorer as a request for stack switching if the SS segment is 'funny'.
This means that anything that tries to mix glibc's signal handling with
segmentation (for instance through modify_ldt syscall) is randomly broken
depending on what values lands in sa_restorer.
The testcase added is based on Linux test tools/testing/selftests/x86/ldt_gdt.c,
more specifically in do_multicpu_tests function. The main changes are:
- C11 atomics instead of plain access.
- Remove x86_64 support which simplifies the syscall handling and fallbacks.
- Replicate only the test required to trigger the issue.
Checked on i686-linux-gnu.
[BZ #21269]
* sysdeps/unix/sysv/linux/i386/Makefile (tests): Add tst-bz21269.
* sysdeps/unix/sysv/linux/i386/sigaction.c (SET_SA_RESTORER): Clear
sa_restorer for vDSO case.
* sysdeps/unix/sysv/linux/i386/tst-bz21269.c: New file.
DJ Delorie [Fri, 2 Mar 2018 04:20:45 +0000 (23:20 -0500)]
[BZ #22342] Fix netgroup cache keys.
Unlike other nscd caches, the netgroup cache contains two types of
records - those for "iterate through a netgroup" (i.e. setnetgrent())
and those for "is this user in this netgroup" (i.e. innetgr()),
i.e. full and partial records. The timeout code assumes these records
have the same key for the group name, so that the collection of records
that is "this netgroup" can be expired as a unit.
However, the keys are not the same, as the in-netgroup key is generated
by nscd rather than being passed to it from elsewhere, and is generated
without the trailing NUL. All other keys have the trailing NUL, and as
noted in the linked BZ, debug statements confirm that two keys for the
same netgroup are added to the cache with two different lengths.
The result of this is that as records in the cache expire, the purge
code only cleans out one of the two types of entries, resulting in
stale, possibly incorrect, and possibly inconsistent cache data.
The patch simply includes the existing NUL in the computation for the
key length ('key' points to the char after the NUL, and 'group' to the
first char of the group, so 'key-group' includes the first char to the
NUL, inclusive).
[BZ #22342]
* nscd/netgroupcache.c (addinnetgrX): Include trailing NUL in
key value.
powerpc: Undefine Linux ptrace macros that conflict with __ptrace_request
Linux ptrace headers define macros whose tokens conflict with the
constants of enum __ptrace_request causing build errors when
asm/ptrace.h or linux/ptrace.h are included before sys/ptrace.h.
* sysdeps/unix/sysv/linux/powerpc/sys/ptrace.h: Undefine Linux
macros used in __ptrace_request.
Rical Jasan [Mon, 19 Feb 2018 11:30:06 +0000 (03:30 -0800)]
manual: Document missing feature test macros.
Several feature test macros are documented in features.h but absent in
the manual, and some documented macros accept undocumented values.
This commit updates the manual to mention all the accepted macros,
along with any values that hold special meaning.
* manual/creature.texi (_POSIX_C_SOURCE): Document special
values of 199606L, 200112L, and 200809L.
(_XOPEN_SOURCE): Document special values of 600 and 700.
(_ISOC11_SOURCE): Document macro.
(_ATFILE_SOURCE): Likewise.
(_FORTIFY_SOURCE): Likewise.
Aurelien Jarno [Thu, 8 Mar 2018 23:14:27 +0000 (00:14 +0100)]
sparc32: Add nop before __startcontext to stop unwinding [BZ #22919]
On sparc32 tst-makecontext fails, as backtrace called within a context
created by makecontext to yield infinite backtrace.
Fix that the same way than nios2 by adding a nop just before
__startcontext. This is needed as otherwise FDE lookup just repeatedly
finds __setcontext's FDE in an infinite loop, due to the convention of
using 'address - 1' for FDE lookup.