Jia Tan [Wed, 19 Apr 2023 14:22:16 +0000 (22:22 +0800)]
Windows: Include <intrin.h> when needed.
Legacy Windows did not need to #include <intrin.h> to use the MSVC
intrinsics. Newer versions likely just issue a warning, but the MSVC
documentation says to include the header file for the intrinsics we use.
GCC and Clang can "pretend" to be MSVC on Windows, so extra checks are
needed in tuklib_integer.h to only include <intrin.h> when it will is
actually needed.
Jia Tan [Wed, 19 Apr 2023 13:59:03 +0000 (21:59 +0800)]
tuklib_integer: Use __builtin_clz() with Clang.
Clang has support for __builtin_clz(), but previously Clang would
fallback to either the MSVC intrinsic or the regular C code. This was
discovered due to a bug where a new version of Clang required the
<intrin.h> header file in order to use the MSVC intrinsics.
Thanks to Anton Kochkov for notifying us about the bug.
Lasse Collin [Tue, 21 Mar 2023 12:04:37 +0000 (14:04 +0200)]
Build: configure.ac: Use AS_IF and AS_CASE where required.
This makes no functional difference in the generated configure
(at least with the Autotools versions I have installed) but this
change might prevent future bugs like the one that was just
fixed in the commit 5a5bd7f871818029d5ccbe189f087f591258c294.
Lasse Collin [Tue, 21 Mar 2023 11:11:49 +0000 (13:11 +0200)]
Build: Fix --disable-threads breaking the building of shared libs.
This is broken in the releases 5.2.6 to 5.4.2. A workaround
for these releases is to pass EGREP='grep -E' as an argument
to configure in addition to --disable-threads.
The problem appeared when m4/ax_pthread.m4 was updated in
the commit 6629ed929cc7d45a11e385f357ab58ec15e7e4ad which
introduced the use of AC_EGREP_CPP. AC_EGREP_CPP calls
AC_REQUIRE([AC_PROG_EGREP]) to set the shell variable EGREP
but this was only executed if POSIX threads were enabled.
Libtool code also has AC_REQUIRE([AC_PROG_EGREP]) but Autoconf
omits it as AC_PROG_EGREP has already been required earlier.
Thus, if not using POSIX threads, the shell variable EGREP
would be undefined in the Libtool code in configure.
ax_pthread.m4 is fine. The bug was in configure.ac which called
AX_PTHREAD conditionally in an incorrect way. Using AS_CASE
ensures that all AC_REQUIREs get always run.
Thanks to Frank Busse for reporting the bug. Fixes: https://github.com/tukaani-project/xz/issues/45
Lasse Collin [Tue, 21 Feb 2023 20:57:10 +0000 (22:57 +0200)]
liblzma: Avoid null pointer + 0 (undefined behavior in C).
In the C99 and C17 standards, section 6.5.6 paragraph 8 means that
adding 0 to a null pointer is undefined behavior. As of writing,
"clang -fsanitize=undefined" (Clang 15) diagnoses this. However,
I'm not aware of any compiler that would take advantage of this
when optimizing (Clang 15 included). It's good to avoid this anyway
since compilers might some day infer that pointer arithmetic implies
that the pointer is not NULL. That is, the following foo() would then
unconditionally return 0, even for foo(NULL, 0):
void bar(char *a, char *b);
int foo(char *a, size_t n)
{
bar(a, a + n);
return a == NULL;
}
In contrast to C, C++ explicitly allows null pointer + 0. So if
the above is compiled as C++ then there is no undefined behavior
in the foo(NULL, 0) call.
To me it seems that changing the C standard would be the sane
thing to do (just add one sentence) as it would ensure that a huge
amount of old code won't break in the future. Based on web searches
it seems that a large number of codebases (where null pointer + 0
occurs) are being fixed instead to be future-proof in case compilers
will some day optimize based on it (like making the above foo(NULL, 0)
return 0) which in the worst case will cause security bugs.
Some projects don't plan to change it. For example, gnulib and thus
many GNU tools currently require that null pointer + 0 is defined:
In XZ Utils null pointer + 0 issue should be fixed after this
commit. This adds a few if-statements and thus branches to avoid
null pointer + 0. These check for size > 0 instead of ptr != NULL
because this way bugs where size > 0 && ptr == NULL will likely
get caught quickly. None of them are in hot spots so it shouldn't
matter for performance.
Checking for offset != 0 instead of ptr != NULL allows GCC >= 8.1,
Clang >= 7, and Clang-based ICX to optimize it to the very same code
as ptr + offset. That is, it won't create a branch. So for hot code
this could be a good solution to avoid null pointer + 0. Unfortunately
other compilers like ICC 2021 or MSVC 19.33 (VS2022) will create a
branch from my_ptr_add().
Thanks to Marcin Kowalczyk for reporting the problem:
https://github.com/tukaani-project/xz/issues/36
Lasse Collin [Fri, 17 Feb 2023 18:48:28 +0000 (20:48 +0200)]
Build: Use only the generic symbol versioning on MicroBlaze.
On MicroBlaze, GCC 12 is broken in sense that
__has_attribute(__symver__) returns true but it still doesn't
support the __symver__ attribute even though the platform is ELF
and symbol versioning is supported if using the traditional
__asm__(".symver ...") method. Avoiding the traditional method is
good because it breaks LTO (-flto) builds with GCC.
See also: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101766
For now the only extra symbols in liblzma_linux.map are the
compatibility symbols with the patch that spread from RHEL/CentOS 7.
These require the use of __symver__ attribute or __asm__(".symver ...")
in the C code. Compatibility with the patch from CentOS 7 doesn't
seem valuable on MicroBlaze so use liblzma_generic.map on MicroBlaze
instead. It doesn't require anything special in the C code and thus
no LTO issues either.
An alternative would be to detect support for __symver__
attribute in configure.ac and CMakeLists.txt and fall back
to __asm__(".symver ...") but then LTO would be silently broken
on MicroBlaze. It sounds likely that MicroBlaze is a special
case so let's treat it as a such because that is simpler. If
a similar issue exists on some other platform too then hopefully
someone will report it and this can be reconsidered.
(This doesn't do the same fix in CMakeLists.txt. Perhaps it should
but perhaps CMake build of liblzma doesn't matter much on MicroBlaze.
The problem breaks the build so it's easy to notice and can be fixed
later.)
Thanks to Vincent Fazio for reporting the problem and proposing
a patch (in the end that solution wasn't used):
https://github.com/tukaani-project/xz/pull/32
Jia Tan [Thu, 19 Jan 2023 12:35:09 +0000 (20:35 +0800)]
tuklib_physmem: Silence warning from -Wcast-function-type on MinGW-w64.
tuklib_physmem depends on GetProcAddress() for both MSVC and MinGW-w64
to retrieve a function address. The proper way to do this is to cast the
return value to the type of function pointer retrieved. Unfortunately,
this causes a cast-function-type warning, so the best solution is to
simply ignore the warning.
Jia Tan [Mon, 16 Jan 2023 12:55:10 +0000 (20:55 +0800)]
xz: Do not set compression settings with raw format in list mode.
Calling coder_set_compression_settings() in list mode with verbose mode
on caused the filter chain and memory requirements to print. This was
unnecessary since the command results in an error and not consistent
with other formats like lzma and alone.
Lasse Collin [Thu, 12 Jan 2023 01:19:59 +0000 (03:19 +0200)]
liblzma: Silence warnings from clang -Wconditional-uninitialized.
This is similar to 2ce4f36f179a81d0c6e182a409f363df759d1ad0.
The actual initialization of the variables is done inside
mythread_sync() macro. Clang doesn't seem to see that
the initialization code inside the macro is always executed.
Jia Tan [Wed, 11 Jan 2023 14:46:48 +0000 (22:46 +0800)]
xz: Fix warning -Wformat-nonliteral on clang in message.c.
clang and gcc differ in how they handle -Wformat-nonliteral. gcc will
allow a non-literal format string as long as the function takes its
format arguments as a va_list.
Lasse Collin [Thu, 8 Dec 2022 17:18:16 +0000 (19:18 +0200)]
xz: Don't modify argv[].
The code that parses --memlimit options and --block-list modified
the argv[] when parsing the option string from optarg. This was
visible in "ps auxf" and such and could be confusing. I didn't
understand it back in the day when I wrote that code. Now a copy
is allocated when modifiable strings are needed.
Lasse Collin [Thu, 8 Dec 2022 15:30:09 +0000 (17:30 +0200)]
liblzma: Check for unexpected NULL pointers in block_header_decode().
The API docs gave an impression that such checks are done
but they actually weren't done. In practice it made little
difference since the calling code has a bug if these are NULL.
Thanks to Jia Tan for the original patch that checked for
block->filters == NULL.
Lasse Collin [Thu, 1 Dec 2022 18:04:17 +0000 (20:04 +0200)]
liblzma: Use __has_attribute(__symver__) to fix Clang detection.
If someone sets up Clang to define __GNUC__ to 10 or greater
then symvers broke. __has_attribute is supported by such GCC
and Clang versions that don't support __symver__ so this should
be much better and simpler way to detect if __symver__ is
actually supported.
Lasse Collin [Thu, 24 Nov 2022 12:52:44 +0000 (14:52 +0200)]
Build: Don't put GNU/Linux-specific symbol versions into static liblzma.
It not only makes no sense to put symbol versions into a static library
but it can also cause breakage.
By default Libtool #defines PIC if building a shared library and
doesn't define it for static libraries. This is documented in the
Libtool manual. It can be overriden using --with-pic or --without-pic.
configure.ac detects if --with-pic or --without-pic is used and then
gives an error if neither --disable-shared nor --disable-static was
used at the same time. Thus, in normal situations it works to build
both shared and static library at the same time on GNU/Linux,
only --with-pic or --without-pic requires that only one type of
library is built.
Thanks to John Paul Adrian Glaubitz from Debian for reporting
the problem that occurred on ia64:
https://www.mail-archive.com/xz-devel@tukaani.org/msg00610.html
Lasse Collin [Wed, 23 Nov 2022 23:26:37 +0000 (01:26 +0200)]
liblzma: Fix another invalid free() after memory allocation failure.
This time it can happen when lzma_stream_encoder_mt() is used
to reinitialize an existing multi-threaded Stream encoder
and one of 1-4 tiny allocations in lzma_filters_copy() fail.
It's very similar to the previous bug 10430fbf3820dafd4eafd38ec8be161a6978ed2b, happening with
an array of lzma_filter structures whose old options are freed
but the replacement never arrives due to a memory allocation
failure in lzma_filters_copy().
Jia Tan [Thu, 5 May 2022 12:53:42 +0000 (20:53 +0800)]
liblzma: Add support for LZMA_SYNC_FLUSH in the Block encoder.
The documentation mentions that lzma_block_encoder() supports
LZMA_SYNC_FLUSH but it was never added to supported_actions[]
in the internal structure. Because of this, LZMA_SYNC_FLUSH could
not be used with the Block encoder unless it was the next coder
after something like stream_encoder() or stream_encoder_mt().
Lasse Collin [Wed, 23 Nov 2022 19:26:21 +0000 (21:26 +0200)]
liblzma: Fix invalid free() after memory allocation failure.
The bug was in the single-threaded .xz Stream encoder
in the code that is used for both re-initialization and for
lzma_filters_update(). To trigger it, an application had
to either re-initialize an existing encoder instance with
lzma_stream_encoder() or use lzma_filters_update(), and
then one of the 1-4 tiny allocations in lzma_filters_copy()
(called from stream_encoder_update()) must fail. An error
was correctly reported but the encoder state was corrupted.
Lasse Collin [Tue, 22 Nov 2022 09:20:17 +0000 (11:20 +0200)]
liblzma: Fix infinite loop in LZMA encoder init with dict_size >= 2 GiB.
The encoder doesn't support dictionary sizes larger than 1536 MiB.
This is validated, for example, when calculating the memory usage
via lzma_raw_encoder_memusage(). It is also enforced by the LZ
part of the encoder initialization. However, LZMA encoder with
LZMA_MODE_NORMAL did an unsafe calculation with dict_size before
such validation and that results in an infinite loop if dict_size
was 2 << 30 or greater.
Lasse Collin [Fri, 11 Nov 2022 12:35:58 +0000 (14:35 +0200)]
liblzma: Fix incorrect #ifdef for x86 SSE2 support.
__SSE2__ is the correct macro for SSE2 support with GCC, Clang,
and ICC. __SSE2_MATH__ means doing floating point math with SSE2
instead of 387. Often the latter macro is defined if the first
one is but it was still a bug.
Lasse Collin [Fri, 11 Nov 2022 10:23:58 +0000 (12:23 +0200)]
Scripts: Ignore warnings from xz.
In practice this means making the scripts work when
the input files have an unsupported check type which
isn't a problem in practice unless support for
some check types has been disabled at build time.
Lasse Collin [Wed, 9 Nov 2022 12:10:52 +0000 (14:10 +0200)]
xz: Add comments about stdin and src_st.st_size.
"xz -v < regular_file > out.xz" doesn't display the percentage
and estimated remaining time because it doesn't even try to
check the input file size when input is read from stdin.
This could be improved but for now there's just a comment
to remind about it.
Lasse Collin [Wed, 9 Nov 2022 10:48:22 +0000 (12:48 +0200)]
xz: Fix displaying of file sizes in progress indicator in passthru mode.
It worked for one input file since the counters are zero when
xz starts but they weren't reset when starting a new file in
passthru mode. For example, if files A, B, and C are one byte each,
then "xz -dcvf A B C" would show file sizes as 1, 2, and 3 bytes
instead of 1, 1, and 1 byte.
Lasse Collin [Mon, 31 Oct 2022 11:31:58 +0000 (13:31 +0200)]
Windows: Fix mythread_once() macro with Vista threads.
Don't call InitOnceComplete() if initialization was already done.
So far mythread_once() has been needed only when building
with --enable-small. windows/build.bash does this together
with --disable-threads so the Vista-specific mythread_once()
is never needed by those builds. VS project files or
CMake-builds don't support HAVE_SMALL builds at all.
The code, that is tries to catch some input file issues early,
didn't anticipate LZMA_STREAM_END which is possible in that
code only when --single-stream is used.
Lasse Collin [Tue, 25 Oct 2022 16:07:17 +0000 (19:07 +0300)]
xz: Fix decompressor behavior if input uses an unsupported check type.
Now files with unsupported check will make xz display
a warning, set the exit status to 2 (unless --no-warn is used),
and then decompress the file normally. This is how it was
supposed to work since the beginning but this was broken by
the commit 231c3c7098f1099a56abb8afece76fc9b8699f05, that is,
a little before 5.0.0 was released. The buggy behavior displayed
a message, set exit status 1 (error), and xz didn't attempt to
to decompress the file.
This doesn't matter today except for special builds that disable
CRC64 or SHA-256 at build time (but such builds should be used
in special situations only). The bug matters if new check type
is added in the future and an old xz version is used to decompress
such a file; however, it's likely that such files would use a new
filter too and an old xz wouldn't be able to decompress the file
anyway.
The first hunk in the commit is the actual fix. The second hunk
is a cleanup since LZMA_TELL_ANY_CHECK isn't used in xz.
There is a test file for unsupported check type but it wasn't
used by test_files.sh, perhaps due to different behavior between
xz and the simpler xzdec.
Lasse Collin [Tue, 25 Oct 2022 15:23:54 +0000 (18:23 +0300)]
xz: If input file cannot be removed, treat it as a warning, not error.
Treating it as a warning (message + exit status 2) matches gzip
and it seems more logical as at that point the output file has
already been successfully closed. When it's a warning it is
possible to suppress it with --no-warn.
Lasse Collin [Thu, 20 Oct 2022 17:22:50 +0000 (20:22 +0300)]
tuklib_cpucores: Use HW_NCPUONLINE on OpenBSD.
On OpenBSD the number of cores online is often less
than what HW_NCPU would return because OpenBSD disables
simultaneous multi-threading (SMT) by default.
Lasse Collin [Thu, 10 Nov 2022 10:34:43 +0000 (12:34 +0200)]
Translations: Rename poa4/fr_FR.po to po4a/fr.po.
That's how it is preferred at the Translation Project.
On my system /usr/share/man/fr_FR doesn't contain any
other man pages than XZ Utils while /usr/share/man/fr
has quite a few, so this will fix that too.
Thanks to Benno Schulenberg from the Translation Project.
Jia Tan [Wed, 21 Sep 2022 08:15:50 +0000 (16:15 +0800)]
liblzma: Add dest and src NULL checks to lzma_index_cat.
The documentation states LZMA_PROG_ERROR can be returned from
lzma_index_cat. Previously, lzma_index_cat could not return
LZMA_PROG_ERROR. Now, the validation is similar to
lzma_index_append, which does a NULL check on the index
parameter.
Jia Tan [Wed, 21 Sep 2022 11:28:53 +0000 (19:28 +0800)]
liblzma: Fix copying of check type statistics in lzma_index_cat().
The check type of the last Stream in dest was never copied to
dest->checks (the code tried to copy it but it was done too late).
This meant that the value returned by lzma_index_checks() would
only include the check type of the last Stream when multiple
lzma_indexes had been concatenated.
In xz --list this meant that the summary would only list the
check type of the last Stream, so in this sense this was only
a visual bug. However, it's possible that some applications
use this information for purposes other than merely showing
it to the users in an informational message. I'm not aware of
such applications though and it's quite possible that such
applications don't exist.
Regular streamed decompression in xz or any other application
doesn't use lzma_index_cat() and so this bug cannot affect them.
Lasse Collin [Wed, 28 Sep 2022 08:05:15 +0000 (11:05 +0300)]
liblzma: Stream decoder: Fix restarting after LZMA_MEMLIMIT_ERROR.
If lzma_code() returns LZMA_MEMLIMIT_ERROR it is now possible
to use lzma_memlimit_set() to increase the limit and continue
decoding. This was supposed to work from the beginning but
there was a bug. With other decoders (.lzma or threaded .xz)
this already worked correctly.
Lasse Collin [Fri, 9 Sep 2022 10:51:57 +0000 (13:51 +0300)]
liblzma: lzma_filters_copy: Keep dest[] unmodified if an error occurs.
lzma_stream_encoder() and lzma_stream_encoder_mt() always assumed
this. Before this patch, failing lzma_filters_copy() could result
in free(invalid_pointer) or invalid memory reads in stream_encoder.c
or stream_encoder_mt.c.
To trigger this, allocating memory for a filter options structure
has to fail. These are tiny allocations so in practice they very
rarely fail.
Certain badness in the filter chain array could also make
lzma_filters_copy() fail but both stream_encoder.c and
stream_encoder_mt.c validate the filter chain before
trying to copy it, so the crash cannot occur this way.
test_files.sh now runs xz -l for bad-3-index-uncomp-overflow.xz
because only then the previously-buggy code path gets tested.
Normal decompression doesn't use lzma_index_append() at all.
Instead, lzma_index_hash functions are used and those already
did the overflow check.
The documentation in src/liblzma/api/lzma/index.h suggests that
both the unpadded (compressed) size and the uncompressed size
are checked for overflow, but only the unpadded size was checked.
The uncompressed check is done first since that is more likely to
occur than the unpadded or index field size overflows.