From 06a27de4468c879494db0e34d37b4ad2e5788af4 Mon Sep 17 00:00:00 2001 From: Nicholas Vinson Date: Mon, 10 Oct 2022 14:22:36 -0400 Subject: [PATCH] Revamp efi_well_known_* variable handling The current implementation attempts to use the linker to create aliases for efi_well_known_guids and efi_well_known_names. It also tries to use the linker to generate the variables efi_well_known_guids_end and efi_well_known_names_end. When building with clang, the generated linker result results in a broken libefivar.so that causes programs to segfault when linked against it. This change does away with linker script hacker and instead introduces pointers to store the locations of efi_well_known_guids_end and efi_well_known_names_end. Additionally, efi_well_known_guids and efi_well_known_names are now created as pointers that point to the beginning of their respective arrays. Signed-off-by: Nicholas Vinson Fixes: #234 --- src/Makefile | 7 ++-- src/include/rules.mk | 5 +-- src/include/workarounds.mk | 24 ------------- src/makeguids.c | 72 +++++++++++++------------------------- 4 files changed, 27 insertions(+), 81 deletions(-) delete mode 100644 src/include/workarounds.mk diff --git a/src/Makefile b/src/Makefile index 0e423c4..a655a56 100644 --- a/src/Makefile +++ b/src/Makefile @@ -4,7 +4,6 @@ include $(TOPDIR)/src/include/deprecated.mk include $(TOPDIR)/src/include/version.mk include $(TOPDIR)/src/include/rules.mk include $(TOPDIR)/src/include/defaults.mk -include $(TOPDIR)/src/include/workarounds.mk LIBTARGETS=libefivar.so libefiboot.so libefisec.so STATICLIBTARGETS=libefivar.a libefiboot.a libefisec.a @@ -30,7 +29,7 @@ EFISECDB_OBJECTS = $(patsubst %.S,%.o,$(patsubst %.c,%.o,$(EFISECDB_SOURCES))) GENERATED_SOURCES = include/efivar/efivar-guids.h guid-symbols.c MAKEGUIDS_SOURCES = makeguids.c util.c MAKEGUIDS_OBJECTS = $(patsubst %.S,%.o,$(patsubst %.c,%.o,$(MAKEGUIDS_SOURCES))) -MAKEGUIDS_OUTPUT = $(GENERATED_SOURCES) guids.lds +MAKEGUIDS_OUTPUT = $(GENERATED_SOURCES) ALL_SOURCES=$(LIBEFISEC_SOURCES) $(LIBEFIBOOT_SOURCES) $(LIBEFIVAR_SOURCES) \ $(MAKEGUIDS_SOURCES) $(GENERATED_SOURCES) $(EFIVAR_SOURCES) \ @@ -81,7 +80,7 @@ $(MAKEGUIDS_OUTPUT) : guids.txt if [ "$${missing}" != "no" ]; then \ exit 1 ; \ fi - ./makeguids $(LD_DASH_T) guids.txt guid-symbols.c include/efivar/efivar-guids.h guids.lds + ./makeguids guids.txt guid-symbols.c include/efivar/efivar-guids.h prep : makeguids $(GENERATED_SOURCES) @@ -93,7 +92,6 @@ libefivar.a : $(patsubst %.o,%.static.o,$(LIBEFIVAR_OBJECTS)) libefivar.so : $(LIBEFIVAR_OBJECTS) libefivar.so : | $(GENERATED_SOURCES) libefivar.map libefivar.so : LIBS=dl -libefivar.so : LDSCRIPTS=guids.lds libefivar.so : MAP=libefivar.map efivar : $(EFIVAR_OBJECTS) | libefivar.so @@ -134,7 +132,6 @@ deps : $(ALL_SOURCES) clean : @rm -rfv *~ *.o *.a *.E *.so *.so.* *.pc *.bin .*.d *.map \ makeguids guid-symbols.c include/efivar/efivar-guids.h \ - guids.lds \ $(TARGETS) $(STATICTARGETS) @# remove the deps files we used to create, as well. @rm -rfv .*.P .*.h.P *.S.P include/efivar/.*.h.P diff --git a/src/include/rules.mk b/src/include/rules.mk index f309f86..8d0b68a 100644 --- a/src/include/rules.mk +++ b/src/include/rules.mk @@ -3,7 +3,6 @@ default : all .PHONY: default all clean install test include $(TOPDIR)/src/include/version.mk -include $(TOPDIR)/src/include/workarounds.mk comma:= , empty:= @@ -36,9 +35,7 @@ family = $(foreach FAMILY_SUFFIX,$(FAMILY_SUFFIXES),$($(1)_$(FAMILY_SUFFIX))) $(CCLD) $(CCLDFLAGS) $(CPPFLAGS) -o $@ $(sort $^) $(LDLIBS) %.so : - $(CCLD) $(CCLDFLAGS) $(CPPFLAGS) $(SOFLAGS) \ - $(foreach LDS,$(LDSCRIPTS),$(LD_DASH_T) $(LDS)) \ - -o $@ $^ $(LDLIBS) + $(CCLD) $(CCLDFLAGS) $(CPPFLAGS) $(SOFLAGS) -o $@ $^ $(LDLIBS) ln -vfs $@ $@.1 %.abixml : %.so diff --git a/src/include/workarounds.mk b/src/include/workarounds.mk deleted file mode 100644 index 3118834..0000000 --- a/src/include/workarounds.mk +++ /dev/null @@ -1,24 +0,0 @@ -# SPDX-License-Identifier: SPDX-License-Identifier: LGPL-2.1-or-later -# -# workarounds.mk - workarounds for weird stuff behavior - -LD_FLAVOR := $(shell $(LD) --version | grep -E '^(LLD|GNU ld)'|sed 's/ .*//g') -LD_VERSION := $(shell $(LD) --version | grep -E '^(LLD|GNU ld)'|sed 's/.* //') -# I haven't tested 2.36 here; 2.35 is definitely broken and 2.37 seems to work -LD_DASH_T := $(shell \ - if [ "x${LD_FLAVOR}" = xLLD ] ; then \ - echo '-T' ; \ - elif [ "x${LD_FLAVOR}" = xGNU ] ; then \ - if echo "${LD_VERSION}" | grep -q -E '^2\.3[789]|^2\.[456789]|^[3456789]|^[[:digit:]][[:digit:]]' ; then \ - echo '-T' ; \ - else \ - echo "" ; \ - fi ; \ - else \ - echo "Your linker is not supported" ; \ - exit 1 ; \ - fi) - -export LD_DASH_T - -# vim:ft=make diff --git a/src/makeguids.c b/src/makeguids.c index e4ff411..b9e9312 100644 --- a/src/makeguids.c +++ b/src/makeguids.c @@ -107,51 +107,46 @@ write_guidnames(FILE *out, const char *listname, gn->symbol, gn->name, gn->description); } fprintf(out, "};\n"); + fprintf(out, "const struct efivar_guidname\n" + "\t__attribute__((__visibility__ (\"default\")))\n" + "\t* const %s = %s_;\n", listname, listname); + fprintf(out, "const struct efivar_guidname\n" + "\t__attribute__((__visibility__ (\"default\")))\n" + "\t* const %s_end = %s_\n\t+ %zd;\n", + listname, listname, n - 1); } int main(int argc, char *argv[]) { int rc; - int argstart = 0; - FILE *symout, *header, *ldsout; - int dash_t = 0; + FILE *symout, *header; - if (argc < 5) { + if (argc < 4) { errx(1, "Not enough arguments.\n"); - } else if (argc > 5 && !strcmp(argv[1],"-T")) { - argstart = 1; - dash_t = 1; - } else if (argc > 5) { + } else if (argc > 4) { errx(1, "Too many arguments.\n"); } - symout = fopen(argv[argstart + 2], "w"); + symout = fopen(argv[2], "w"); if (symout == NULL) - err(1, "could not open \"%s\"", argv[argstart + 2]); - rc = chmod(argv[argstart + 2], 0644); + err(1, "could not open \"%s\"", argv[2]); + rc = chmod(argv[2], 0644); if (rc < 0) - warn("chmod(%s, 0644)", argv[argstart + 2]); + warn("chmod(%s, 0644)", argv[2]); - header = fopen(argv[argstart + 3], "w"); + header = fopen(argv[3], "w"); if (header == NULL) - err(1, "could not open \"%s\"", argv[argstart + 3]); - rc = chmod(argv[argstart + 3], 0644); - if (rc < 0) - warn("chmod(%s, 0644)", argv[argstart + 3]); - - ldsout = fopen(argv[argstart + 4], "w"); - if (ldsout == NULL) - err(1, "could not open \"%s\"", argv[argstart + 4]); - rc = chmod(argv[argstart + 4], 0644); + err(1, "could not open \"%s\"", argv[3]); + rc = chmod(argv[3], 0644); if (rc < 0) - warn("chmod(%s, 0644)", argv[argstart + 4]); + warn("chmod(%s, 0644)", argv[3]); struct guidname_index *guidnames = NULL; - rc = read_guids_at(AT_FDCWD, argv[argstart + 1], &guidnames); + rc = read_guids_at(AT_FDCWD, argv[1], &guidnames); if (rc < 0) - err(1, "could not read \"%s\"", argv[argstart + 1]); + err(1, "could not read \"%s\"", argv[1]); struct efivar_guidname *outbuf; @@ -239,12 +234,11 @@ struct efivar_guidname {\n\ fprintf(header, "extern const struct efivar_guidname\n" "\t__attribute__((__visibility__ (\"default\")))\n" - "\tefi_well_known_guids[%d];\n", - i); + "\t* const efi_well_known_guids;\n"); fprintf(header, "extern const struct efivar_guidname\n" "\t__attribute__((__visibility__ (\"default\")))\n" - "\tefi_well_known_guids_end;\n"); + "\t* const efi_well_known_guids_end;\n"); fprintf(header, "extern const uint64_t\n" "\t__attribute__((__visibility__ (\"default\")))\n" @@ -252,12 +246,11 @@ struct efivar_guidname {\n\ fprintf(header, "extern const struct efivar_guidname\n" "\t__attribute__((__visibility__ (\"default\")))\n" - "\tefi_well_known_names[%d];\n", - i); + "\t* const efi_well_known_names;\n"); fprintf(header, "extern const struct efivar_guidname\n" "\t__attribute__((__visibility__ (\"default\")))\n" - "\tefi_well_known_names_end;\n"); + "\t* const efi_well_known_names_end;\n"); fprintf(header, "extern const uint64_t\n" "\t__attribute__((__visibility__ (\"default\")))\n" @@ -302,23 +295,6 @@ struct efivar_guidname {\n\ fclose(symout); - fprintf(ldsout, - "SECTIONS\n" - "{\n" - " .data :\n" - " {\n" - " efi_well_known_guids = efi_well_known_guids_;\n" - " efi_well_known_guids_end = efi_well_known_guids_ + %zd;\n" - " efi_well_known_names = efi_well_known_names_;\n" - " efi_well_known_names_end = efi_well_known_names_ + %zd;\n" - " }\n" - "}%s;\n", - (line - 1) * sizeof(struct efivar_guidname), - (line - 1) * sizeof(struct efivar_guidname), - dash_t ? " INSERT AFTER .data" : ""); - - fclose(ldsout); - free(guidnames->strtab); free(guidnames); -- 2.35.3