diff --git a/configure.ac b/configure.ac index 7443489a..57f60f69 100644 --- a/configure.ac +++ b/configure.ac @@ -493,7 +493,28 @@ if test "x$enable_symbol_versions" = xauto; then esac fi AC_MSG_RESULT([$enable_symbol_versions]) -AM_CONDITIONAL([COND_SYMVERS], [test "x$enable_symbol_versions" = xyes]) + +# There are two variants for symbol versioning. +# See src/liblzma/validate_map.sh for details. +if test "x$enable_symbol_versions" = xyes; then + case $host_os in + linux*) + enable_symbol_versions=linux + AC_DEFINE([HAVE_SYMBOL_VERSIONS_LINUX], [1], + [Define to 1 to if GNU/Linux-specific details + are wanted for symbol versioning. This must + be used together with liblzma_linux.map.]) + ;; + *) + enable_symbol_versions=generic + ;; + esac +fi + +AM_CONDITIONAL([COND_SYMVERS_LINUX], + [test "x$enable_symbol_versions" = xlinux]) +AM_CONDITIONAL([COND_SYMVERS_GENERIC], + [test "x$enable_symbol_versions" = xgeneric]) ############## diff --git a/src/liblzma/Makefile.am b/src/liblzma/Makefile.am index 6323e26a..d73d5f0a 100644 --- a/src/liblzma/Makefile.am +++ b/src/liblzma/Makefile.am @@ -26,10 +26,14 @@ liblzma_la_CPPFLAGS = \ -DTUKLIB_SYMBOL_PREFIX=lzma_ liblzma_la_LDFLAGS = -no-undefined -version-info 8:99:3 -EXTRA_DIST += liblzma.map validate_map.sh -if COND_SYMVERS +EXTRA_DIST += liblzma_generic.map liblzma_linux.map validate_map.sh +if COND_SYMVERS_GENERIC liblzma_la_LDFLAGS += \ - -Wl,--version-script=$(top_srcdir)/src/liblzma/liblzma.map + -Wl,--version-script=$(top_srcdir)/src/liblzma/liblzma_generic.map +endif +if COND_SYMVERS_LINUX +liblzma_la_LDFLAGS += \ + -Wl,--version-script=$(top_srcdir)/src/liblzma/liblzma_linux.map endif liblzma_la_SOURCES += ../common/tuklib_physmem.c diff --git a/src/liblzma/common/block_buffer_encoder.c b/src/liblzma/common/block_buffer_encoder.c index 39e263aa..a47342ef 100644 --- a/src/liblzma/common/block_buffer_encoder.c +++ b/src/liblzma/common/block_buffer_encoder.c @@ -325,6 +325,24 @@ lzma_block_buffer_encode(lzma_block *block, const lzma_allocator *allocator, } +#ifdef HAVE_SYMBOL_VERSIONS_LINUX +// This is for compatibility with binaries linked against liblzma that +// has been patched with xz-5.2.2-compat-libs.patch from RHEL/CentOS 7. +LZMA_SYMVER_API("lzma_block_uncomp_encode@XZ_5.2.2", + lzma_ret, lzma_block_uncomp_encode_522)(lzma_block *block, + const uint8_t *in, size_t in_size, + uint8_t *out, size_t *out_pos, size_t out_size) + lzma_nothrow lzma_attr_warn_unused_result + __attribute__((__alias__("lzma_block_uncomp_encode_52"))); + +LZMA_SYMVER_API("lzma_block_uncomp_encode@@XZ_5.2", + lzma_ret, lzma_block_uncomp_encode_52)(lzma_block *block, + const uint8_t *in, size_t in_size, + uint8_t *out, size_t *out_pos, size_t out_size) + lzma_nothrow lzma_attr_warn_unused_result; + +#define lzma_block_uncomp_encode lzma_block_uncomp_encode_52 +#endif extern LZMA_API(lzma_ret) lzma_block_uncomp_encode(lzma_block *block, const uint8_t *in, size_t in_size, diff --git a/src/liblzma/common/common.c b/src/liblzma/common/common.c index 346fc7af..a708fdf1 100644 --- a/src/liblzma/common/common.c +++ b/src/liblzma/common/common.c @@ -374,6 +374,20 @@ lzma_end(lzma_stream *strm) } +#ifdef HAVE_SYMBOL_VERSIONS_LINUX +// This is for compatibility with binaries linked against liblzma that +// has been patched with xz-5.2.2-compat-libs.patch from RHEL/CentOS 7. +LZMA_SYMVER_API("lzma_get_progress@XZ_5.2.2", + void, lzma_get_progress_522)(lzma_stream *strm, + uint64_t *progress_in, uint64_t *progress_out) lzma_nothrow + __attribute__((__alias__("lzma_get_progress_52"))); + +LZMA_SYMVER_API("lzma_get_progress@@XZ_5.2", + void, lzma_get_progress_52)(lzma_stream *strm, + uint64_t *progress_in, uint64_t *progress_out) lzma_nothrow; + +#define lzma_get_progress lzma_get_progress_52 +#endif extern LZMA_API(void) lzma_get_progress(lzma_stream *strm, uint64_t *progress_in, uint64_t *progress_out) diff --git a/src/liblzma/common/common.h b/src/liblzma/common/common.h index 36366dbc..4783e45d 100644 --- a/src/liblzma/common/common.h +++ b/src/liblzma/common/common.h @@ -34,6 +34,34 @@ #include "lzma.h" +#ifdef HAVE_SYMBOL_VERSIONS_LINUX +// To keep link-time optimization (LTO, -flto) working with GCC, +// the __symver__ attribute must be used instead of __asm__(".symver ..."). +// Otherwise the symbol versions may be lost, resulting in broken liblzma +// that has wrong default versions in the exported symbol list! +// The attribute was added in GCC 10; LTO with older GCC is not supported. +// +// To keep -Wmissing-prototypes happy, use LZMA_SYMVER_API only with function +// declarations (including those with __alias__ attribute) and LZMA_API with +// the function definitions. This means a little bit of silly copy-and-paste +// between declarations and definitions though. +// +// As of GCC 12.2, the __symver__ attribute supports only @ and @@ but the +// very convenient @@@ isn't supported (it's supported by GNU assembler +// since 2000). When using @@ instead of @@@, the internal name must not be +// the same as the external name to avoid problems in some situations. This +// is why "#define foo_52 foo" is needed for the default symbol versions. +# if TUKLIB_GNUC_REQ(10, 0) +# define LZMA_SYMVER_API(extnamever, type, intname) \ + extern __attribute__((__symver__(extnamever))) \ + LZMA_API(type) intname +# else +# define LZMA_SYMVER_API(extnamever, type, intname) \ + __asm__(".symver " #intname "," extnamever); \ + extern LZMA_API(type) intname +# endif +#endif + // These allow helping the compiler in some often-executed branches, whose // result is almost always the same. #ifdef __GNUC__ diff --git a/src/liblzma/common/hardware_cputhreads.c b/src/liblzma/common/hardware_cputhreads.c index f468366a..5d246d2c 100644 --- a/src/liblzma/common/hardware_cputhreads.c +++ b/src/liblzma/common/hardware_cputhreads.c @@ -15,6 +15,18 @@ #include "tuklib_cpucores.h" +#ifdef HAVE_SYMBOL_VERSIONS_LINUX +// This is for compatibility with binaries linked against liblzma that +// has been patched with xz-5.2.2-compat-libs.patch from RHEL/CentOS 7. +LZMA_SYMVER_API("lzma_cputhreads@XZ_5.2.2", + uint32_t, lzma_cputhreads_522)(void) lzma_nothrow + __attribute__((__alias__("lzma_cputhreads_52"))); + +LZMA_SYMVER_API("lzma_cputhreads@@XZ_5.2", + uint32_t, lzma_cputhreads_52)(void) lzma_nothrow; + +#define lzma_cputhreads lzma_cputhreads_52 +#endif extern LZMA_API(uint32_t) lzma_cputhreads(void) { diff --git a/src/liblzma/common/stream_encoder_mt.c b/src/liblzma/common/stream_encoder_mt.c index 24addd40..fb56a96f 100644 --- a/src/liblzma/common/stream_encoder_mt.c +++ b/src/liblzma/common/stream_encoder_mt.c @@ -1096,6 +1096,31 @@ stream_encoder_mt_init(lzma_next_coder *next, const lzma_allocator *allocator, } +#ifdef HAVE_SYMBOL_VERSIONS_LINUX +// These are for compatibility with binaries linked against liblzma that +// has been patched with xz-5.2.2-compat-libs.patch from RHEL/CentOS 7. +// Actually that patch didn't create lzma_stream_encoder_mt@XZ_5.2.2 +// but it has been added here anyway since someone might misread the +// RHEL patch and think both @XZ_5.1.2alpha and @XZ_5.2.2 exist. +LZMA_SYMVER_API("lzma_stream_encoder_mt@XZ_5.1.2alpha", + lzma_ret, lzma_stream_encoder_mt_512a)( + lzma_stream *strm, const lzma_mt *options) + lzma_nothrow lzma_attr_warn_unused_result + __attribute__((__alias__("lzma_stream_encoder_mt_52"))); + +LZMA_SYMVER_API("lzma_stream_encoder_mt@XZ_5.2.2", + lzma_ret, lzma_stream_encoder_mt_522)( + lzma_stream *strm, const lzma_mt *options) + lzma_nothrow lzma_attr_warn_unused_result + __attribute__((__alias__("lzma_stream_encoder_mt_52"))); + +LZMA_SYMVER_API("lzma_stream_encoder_mt@@XZ_5.2", + lzma_ret, lzma_stream_encoder_mt_52)( + lzma_stream *strm, const lzma_mt *options) + lzma_nothrow lzma_attr_warn_unused_result; + +#define lzma_stream_encoder_mt lzma_stream_encoder_mt_52 +#endif extern LZMA_API(lzma_ret) lzma_stream_encoder_mt(lzma_stream *strm, const lzma_mt *options) { @@ -1111,6 +1136,23 @@ lzma_stream_encoder_mt(lzma_stream *strm, const lzma_mt *options) } +#ifdef HAVE_SYMBOL_VERSIONS_LINUX +LZMA_SYMVER_API("lzma_stream_encoder_mt_memusage@XZ_5.1.2alpha", + uint64_t, lzma_stream_encoder_mt_memusage_512a)( + const lzma_mt *options) lzma_nothrow lzma_attr_pure + __attribute__((__alias__("lzma_stream_encoder_mt_memusage_52"))); + +LZMA_SYMVER_API("lzma_stream_encoder_mt_memusage@XZ_5.2.2", + uint64_t, lzma_stream_encoder_mt_memusage_522)( + const lzma_mt *options) lzma_nothrow lzma_attr_pure + __attribute__((__alias__("lzma_stream_encoder_mt_memusage_52"))); + +LZMA_SYMVER_API("lzma_stream_encoder_mt_memusage@@XZ_5.2", + uint64_t, lzma_stream_encoder_mt_memusage_52)( + const lzma_mt *options) lzma_nothrow lzma_attr_pure; + +#define lzma_stream_encoder_mt_memusage lzma_stream_encoder_mt_memusage_52 +#endif // This function name is a monster but it's consistent with the older // monster names. :-( 31 chars is the max that C99 requires so in that // sense it's not too long. ;-) diff --git a/src/liblzma/liblzma.map b/src/liblzma/liblzma_generic.map similarity index 100% rename from src/liblzma/liblzma.map rename to src/liblzma/liblzma_generic.map index c37f293d..0251c4c2 100644 --- a/src/liblzma/liblzma.map +++ b/src/liblzma/liblzma_generic.map @@ -93,6 +93,9 @@ global: lzma_vli_decode; lzma_vli_encode; lzma_vli_size; + +local: + *; }; XZ_5.2 { @@ -110,7 +113,4 @@ global: lzma_microlzma_encoder; lzma_file_info_decoder; lzma_stream_decoder_mt; - -local: - *; } XZ_5.2; diff --git a/src/liblzma/liblzma_linux.map b/src/liblzma/liblzma_linux.map new file mode 100644 index 00000000..7a09e03c --- /dev/null +++ b/src/liblzma/liblzma_linux.map @@ -0,0 +1,131 @@ +XZ_5.0 { +global: + lzma_alone_decoder; + lzma_alone_encoder; + lzma_auto_decoder; + lzma_block_buffer_bound; + lzma_block_buffer_decode; + lzma_block_buffer_encode; + lzma_block_compressed_size; + lzma_block_decoder; + lzma_block_encoder; + lzma_block_header_decode; + lzma_block_header_encode; + lzma_block_header_size; + lzma_block_total_size; + lzma_block_unpadded_size; + lzma_check_is_supported; + lzma_check_size; + lzma_code; + lzma_crc32; + lzma_crc64; + lzma_easy_buffer_encode; + lzma_easy_decoder_memusage; + lzma_easy_encoder; + lzma_easy_encoder_memusage; + lzma_end; + lzma_filter_decoder_is_supported; + lzma_filter_encoder_is_supported; + lzma_filter_flags_decode; + lzma_filter_flags_encode; + lzma_filter_flags_size; + lzma_filters_copy; + lzma_filters_update; + lzma_get_check; + lzma_index_append; + lzma_index_block_count; + lzma_index_buffer_decode; + lzma_index_buffer_encode; + lzma_index_cat; + lzma_index_checks; + lzma_index_decoder; + lzma_index_dup; + lzma_index_encoder; + lzma_index_end; + lzma_index_file_size; + lzma_index_hash_append; + lzma_index_hash_decode; + lzma_index_hash_end; + lzma_index_hash_init; + lzma_index_hash_size; + lzma_index_init; + lzma_index_iter_init; + lzma_index_iter_locate; + lzma_index_iter_next; + lzma_index_iter_rewind; + lzma_index_memusage; + lzma_index_memused; + lzma_index_size; + lzma_index_stream_count; + lzma_index_stream_flags; + lzma_index_stream_padding; + lzma_index_stream_size; + lzma_index_total_size; + lzma_index_uncompressed_size; + lzma_lzma_preset; + lzma_memlimit_get; + lzma_memlimit_set; + lzma_memusage; + lzma_mf_is_supported; + lzma_mode_is_supported; + lzma_physmem; + lzma_properties_decode; + lzma_properties_encode; + lzma_properties_size; + lzma_raw_buffer_decode; + lzma_raw_buffer_encode; + lzma_raw_decoder; + lzma_raw_decoder_memusage; + lzma_raw_encoder; + lzma_raw_encoder_memusage; + lzma_stream_buffer_bound; + lzma_stream_buffer_decode; + lzma_stream_buffer_encode; + lzma_stream_decoder; + lzma_stream_encoder; + lzma_stream_flags_compare; + lzma_stream_footer_decode; + lzma_stream_footer_encode; + lzma_stream_header_decode; + lzma_stream_header_encode; + lzma_version_number; + lzma_version_string; + lzma_vli_decode; + lzma_vli_encode; + lzma_vli_size; + +local: + *; +}; + +XZ_5.2 { +global: + lzma_block_uncomp_encode; + lzma_cputhreads; + lzma_get_progress; + lzma_stream_encoder_mt; + lzma_stream_encoder_mt_memusage; +} XZ_5.0; + +XZ_5.1.2alpha { +global: + lzma_stream_encoder_mt; + lzma_stream_encoder_mt_memusage; +} XZ_5.0; + +XZ_5.2.2 { +global: + lzma_block_uncomp_encode; + lzma_cputhreads; + lzma_get_progress; + lzma_stream_encoder_mt; + lzma_stream_encoder_mt_memusage; +} XZ_5.1.2alpha; + +XZ_5.3.3alpha { +global: + lzma_microlzma_decoder; + lzma_microlzma_encoder; + lzma_file_info_decoder; + lzma_stream_decoder_mt; +} XZ_5.2; diff --git a/src/liblzma/validate_map.sh b/src/liblzma/validate_map.sh index 3aee4668..2bf6f8b9 100644 --- a/src/liblzma/validate_map.sh +++ b/src/liblzma/validate_map.sh @@ -2,7 +2,79 @@ ############################################################################### # -# Check liblzma.map for certain types of errors +# Check liblzma_*.map for certain types of errors. +# +# liblzma_generic.map is for FreeBSD and Solaris and possibly others +# except GNU/Linux. +# +# liblzma_linux.map is for GNU/Linux only. This and the matching extra code +# in the .c files make liblzma >= 5.2.7 compatible with binaries that were +# linked against ill-patched liblzma in RHEL/CentOS 7. By providing the +# compatibility in official XZ Utils release will hopefully prevent people +# from further copying the broken patch to other places when they want +# compatibility with binaries linked on RHEL/CentOS 7. The long version +# of the story: +# +# RHEL/CentOS 7 shipped with 5.1.2alpha, including the threaded +# encoder that is behind #ifdef LZMA_UNSTABLE in the API headers. +# In 5.1.2alpha these symbols are under XZ_5.1.2alpha in liblzma.map. +# API/ABI compatibility tracking isn't done between development +# releases so newer releases didn't have XZ_5.1.2alpha anymore. +# +# Later RHEL/CentOS 7 updated xz to 5.2.2 but they wanted to keep +# the exported symbols compatible with 5.1.2alpha. After checking +# the ABI changes it turned out that >= 5.2.0 ABI is backward +# compatible with the threaded encoder functions from 5.1.2alpha +# (but not vice versa as fixes and extensions to these functions +# were made between 5.1.2alpha and 5.2.0). +# +# In RHEL/CentOS 7, XZ Utils 5.2.2 was patched with +# xz-5.2.2-compat-libs.patch to modify liblzma.map: +# +# - XZ_5.1.2alpha was added with lzma_stream_encoder_mt and +# lzma_stream_encoder_mt_memusage. This matched XZ Utils 5.1.2alpha. +# +# - XZ_5.2 was replaced with XZ_5.2.2. It is clear that this was +# an error; the intention was to keep using XZ_5.2 (XZ_5.2.2 +# has never been used in XZ Utils). So XZ_5.2.2 lists all +# symbols that were listed under XZ_5.2 before the patch. +# lzma_stream_encoder_mt and _mt_memusage are included too so +# they are listed both here and under XZ_5.1.2alpha. +# +# The patch didn't add any __asm__(".symver ...") lines to the .c +# files. Thus the resulting liblzma.so exports the threaded encoder +# functions under XZ_5.1.2alpha only. Listing the two functions +# also under XZ_5.2.2 in liblzma.map has no effect without +# matching .symver lines. +# +# The lack of XZ_5.2 in RHEL/CentOS 7 means that binaries linked +# against unpatched XZ Utils 5.2.x won't run on RHEL/CentOS 7. +# This is unfortunate but this alone isn't too bad as the problem +# is contained within RHEL/CentOS 7 and doesn't affect users +# of other distributions. It could also be fixed internally in +# RHEL/CentOS 7. +# +# The second problem is more serious: In XZ Utils 5.2.2 the API +# headers don't have #ifdef LZMA_UNSTABLE for obvious reasons. +# This is true in RHEL/CentOS 7 version too. Thus now programs +# using new APIs can be compiled without an extra #define. However, +# the programs end up depending on symbol version XZ_5.1.2alpha +# (and possibly also XZ_5.2.2) instead of XZ_5.2 as they would +# with an unpatched XZ Utils 5.2.2. This means that such binaries +# won't run on other distributions shipping XZ Utils >= 5.2.0 as +# they don't provide XZ_5.1.2alpha or XZ_5.2.2; they only provide +# XZ_5.2 (and XZ_5.0). (This includes RHEL/CentOS 8 as the patch +# luckily isn't included there anymore with XZ Utils 5.2.4.) +# +# Binaries built by RHEL/CentOS 7 users get distributed and then +# people wonder why they don't run on some other distribution. +# Seems that people have found out about the patch and been copying +# it to some build scripts, seemingly curing the symptoms but +# actually spreading the illness further and outside RHEL/CentOS 7. +# Adding compatibility in an official XZ Utils release should work +# as a vaccine against this ill patch and stop it from spreading. +# The vaccine is kept GNU/Linux-only as other OSes should be immune +# (hopefully it hasn't spread via some build script to other OSes). # # Author: Lasse Collin # @@ -18,11 +90,11 @@ STATUS=0 cd "$(dirname "$0")" -# Get the list of symbols that aren't defined in liblzma.map. +# Get the list of symbols that aren't defined in liblzma_generic.map. SYMS=$(sed -n 's/^extern LZMA_API([^)]*) \([a-z0-9_]*\)(.*$/\1;/p' \ api/lzma/*.h \ | sort \ - | grep -Fve "$(sed '/[{}:*]/d;/^$/d;s/^ //' liblzma.map)") + | grep -Fve "$(sed '/[{}:*]/d;/^$/d;s/^ //' liblzma_generic.map)") # Check that there are no old alpha or beta versions listed. VER=$(cd ../.. && sh build-aux/version.sh) @@ -30,21 +102,41 @@ NAMES= case $VER in *alpha | *beta) NAMES=$(sed -n 's/^.*XZ_\([^ ]*\)\(alpha\|beta\) .*$/\1\2/p' \ - liblzma.map | grep -Fv "$VER") + liblzma_generic.map | grep -Fv "$VER") ;; esac # Check for duplicate lines. It can catch missing dependencies. -DUPS=$(sort liblzma.map | sed '/^$/d;/^global:$/d' | uniq -d) +DUPS=$(sort liblzma_generic.map | sed '/^$/d;/^global:$/d' | uniq -d) + +# Check that liblzma_linux.map is in sync with liblzma_generic.map. +# The RHEL/CentOS 7 compatibility symbols are in a fixed location +# so it makes it easy to remove them for comparison with liblzma_generic.map. +# +# NOTE: Putting XZ_5.2 before the compatibility symbols XZ_5.1.2alpha +# and XZ_5.2.2 in liblzma_linux.map is important: If liblzma_linux.map is +# incorrectly used without #define HAVE_SYMBOL_VERSIONS_LINUX, only the first +# occurrence of each function name will be used from liblzma_linux.map; +# the rest are ignored by the linker. Thus having XZ_5.2 before the +# compatibility symbols means that @@XZ_5.2 will be used for the symbols +# listed under XZ_5.2 {...} and the same function names later in +# the file under XZ_5.1.2alpha {...} and XZ_5.2.2 {...} will be +# ignored (@XZ_5.1.2alpha or @XZ_5.2.2 won't be added at all when +# the #define HAVE_SYMBOL_VERSIONS_LINUX isn't used). +IN_SYNC= +if ! sed '109,123d' liblzma_linux.map \ + | cmp -s - liblzma_generic.map; then + IN_SYNC=no +fi # Print error messages if needed. -if test -n "$SYMS$NAMES$DUPS"; then +if test -n "$SYMS$NAMES$DUPS$IN_SYNC"; then echo - echo 'validate_map.sh found problems from liblzma.map:' + echo 'validate_map.sh found problems from liblzma_*.map:' echo if test -n "$SYMS"; then - echo 'liblzma.map lacks the following symbols:' + echo 'liblzma_generic.map lacks the following symbols:' echo "$SYMS" echo fi @@ -61,6 +153,11 @@ if test -n "$SYMS$NAMES$DUPS"; then echo fi + if test -n "$IN_SYNC"; then + echo "liblzma_generic.map and liblzma_linux.map aren't in sync" + echo + fi + STATUS=1 fi