diff options
Diffstat (limited to 'libre/syslinux/syslinux-6.02-fix-efi-ovmf.patch')
| -rw-r--r-- | libre/syslinux/syslinux-6.02-fix-efi-ovmf.patch | 621 |
1 files changed, 621 insertions, 0 deletions
diff --git a/libre/syslinux/syslinux-6.02-fix-efi-ovmf.patch b/libre/syslinux/syslinux-6.02-fix-efi-ovmf.patch new file mode 100644 index 000000000..f33f4c1de --- /dev/null +++ b/libre/syslinux/syslinux-6.02-fix-efi-ovmf.patch @@ -0,0 +1,621 @@ +The value of the field rva_and_sizes_nr is used by OVMF to check the +consistency of the PE file with respect to the field optional_hdr_sz. It +now have the right value. + +Signed-off-by: Celelibi <celelibi at gmail.com> +--- + efi/wrapper.c | 6 +++--- + efi/wrapper.h | 28 ++++++++++++++++------------ + 2 files changed, 19 insertions(+), 15 deletions(-) + +diff --git a/efi/wrapper.c b/efi/wrapper.c +index 04c895f..ec77271 100644 +--- a/efi/wrapper.c ++++ b/efi/wrapper.c +@@ -102,7 +102,7 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + e_hdr.image_sz = total_sz; + e_hdr.headers_sz = 512; + e_hdr.subsystem = IMAGE_SUBSYSTEM_EFI_APPLICATION; +- e_hdr.rva_and_sizes_nr = 1; ++ e_hdr.rva_and_sizes_nr = sizeof(e_hdr.data_directory) / sizeof(__uint64_t); + fwrite(&e_hdr, sizeof(e_hdr), 1, f); + } + else if (class == ELFCLASS64) { +@@ -130,7 +130,7 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + e_hdr_pe32p.image_sz = total_sz; + e_hdr_pe32p.headers_sz = 512; + e_hdr_pe32p.subsystem = IMAGE_SUBSYSTEM_EFI_APPLICATION; +- e_hdr_pe32p.rva_and_sizes_nr = 1; ++ e_hdr_pe32p.rva_and_sizes_nr = sizeof(e_hdr_pe32p.data_directory) / sizeof(__uint64_t); + fwrite(&e_hdr_pe32p, sizeof(e_hdr_pe32p), 1, f); + } + +@@ -237,7 +237,7 @@ int main(int argc, char **argv) + fprintf(stderr, "Unsupported architecture\n"); + exit(EXIT_FAILURE); + } +- ++ + if (id[EI_MAG0] != ELFMAG0 || + id[EI_MAG1] != ELFMAG1 || + id[EI_MAG2] != ELFMAG2 || +diff --git a/efi/wrapper.h b/efi/wrapper.h +index 4f76991..0e6b38e 100644 +--- a/efi/wrapper.h ++++ b/efi/wrapper.h +@@ -102,12 +102,14 @@ struct extra_hdr { + __uint32_t heap_commit_sz; + __uint32_t loader_flags; + __uint32_t rva_and_sizes_nr; +- __uint64_t export_table; +- __uint64_t import_table; +- __uint64_t resource_table; +- __uint64_t exception_table; +- __uint64_t certification_table; +- __uint64_t base_relocation_table; ++ struct { ++ __uint64_t export_table; ++ __uint64_t import_table; ++ __uint64_t resource_table; ++ __uint64_t exception_table; ++ __uint64_t certification_table; ++ __uint64_t base_relocation_table; ++ } data_directory; + } __packed; + + /* Extra header for PE32+ format +@@ -136,12 +138,14 @@ struct extra_hdr_pe32p { + __uint64_t heap_commit_sz; + __uint32_t loader_flags; + __uint32_t rva_and_sizes_nr; +- __uint64_t export_table; +- __uint64_t import_table; +- __uint64_t resource_table; +- __uint64_t exception_table; +- __uint64_t certification_table; +- __uint64_t base_relocation_table; ++ struct { ++ __uint64_t export_table; ++ __uint64_t import_table; ++ __uint64_t resource_table; ++ __uint64_t exception_table; ++ __uint64_t certification_table; ++ __uint64_t base_relocation_table; ++ } data_directory; + } __packed; + + struct section { +In the generated PE file, the section header for the .text section used +to address more than the whole file. Starting at offset 0 (before the +end of the headers) is illegal and is rejected by OVMF. Giving a size +greater than the actual file size is also illegal and rejected. + +Moreover, the actual data inside the PE file have to be aligned to at +least 512 bytes. Hence, .text need to be aligned as well. + +Signed-off-by: Celelibi <celelibi at gmail.com> +--- + efi/wrapper.c | 44 +++++++++++++++++++++++++------------------- + 1 file changed, 25 insertions(+), 19 deletions(-) + +diff --git a/efi/wrapper.c b/efi/wrapper.c +index ec77271..bd2c175 100644 +--- a/efi/wrapper.c ++++ b/efi/wrapper.c +@@ -54,11 +54,15 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + struct coff_hdr c_hdr; + struct header hdr; + struct coff_reloc c_rel; +- __uint32_t total_sz = so_size; ++ __uint32_t total_sz = data_size; + __uint32_t dummy = 0; + __uint32_t hdr_sz; + __uint32_t reloc_start, reloc_end; + ++ hdr_sz = 512; ++ total_sz += hdr_sz; ++ entry += hdr_sz; ++ + memset(&hdr, 0, sizeof(hdr)); + hdr.msdos_signature = MSDOS_SIGNATURE; + +@@ -77,11 +81,6 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + c_hdr.nr_sections = 2; + c_hdr.nr_syms = 1; + if (class == ELFCLASS32) { +- hdr_sz = sizeof(o_hdr) + sizeof(t_sec) + sizeof(e_hdr) + +- sizeof(r_sec) + sizeof(c_hdr) + sizeof(hdr) + sizeof(c_rel) +- + sizeof(dummy); +- total_sz += hdr_sz; +- entry += hdr_sz; + c_hdr.arch = IMAGE_FILE_MACHINE_I386; + c_hdr.characteristics = IMAGE_FILE_32BIT_MACHINE | + IMAGE_FILE_DEBUG_STRIPPED | IMAGE_FILE_EXECUTABLE_IMAGE | +@@ -92,25 +91,20 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + o_hdr.format = PE32_FORMAT; + o_hdr.major_linker_version = 0x02; + o_hdr.minor_linker_version = 0x14; +- o_hdr.code_sz = total_sz; ++ o_hdr.code_sz = data_size; + o_hdr.entry_point = entry; + o_hdr.initialized_data_sz = data_size; + fwrite(&o_hdr, sizeof(o_hdr), 1, f); + memset(&e_hdr, 0, sizeof(e_hdr)); + e_hdr.section_align = 4096; + e_hdr.file_align = 512; +- e_hdr.image_sz = total_sz; +- e_hdr.headers_sz = 512; ++ e_hdr.image_sz = hdr_sz + so_size; ++ e_hdr.headers_sz = hdr_sz; + e_hdr.subsystem = IMAGE_SUBSYSTEM_EFI_APPLICATION; + e_hdr.rva_and_sizes_nr = sizeof(e_hdr.data_directory) / sizeof(__uint64_t); + fwrite(&e_hdr, sizeof(e_hdr), 1, f); + } + else if (class == ELFCLASS64) { +- hdr_sz = sizeof(o_hdr_pe32p) + sizeof(t_sec) + sizeof(e_hdr_pe32p) + +- sizeof(r_sec) + sizeof(c_hdr) + sizeof(hdr) + sizeof(c_rel) +- + sizeof(dummy); +- total_sz += hdr_sz; +- entry += hdr_sz; + c_hdr.arch = IMAGE_FILE_MACHINE_X86_64; + c_hdr.characteristics = IMAGE_FILE_DEBUG_STRIPPED | IMAGE_FILE_EXECUTABLE_IMAGE | + IMAGE_FILE_LINE_NUMBERS_STRIPPED; +@@ -120,15 +114,15 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + o_hdr_pe32p.format = PE32P_FORMAT; + o_hdr_pe32p.major_linker_version = 0x02; + o_hdr_pe32p.minor_linker_version = 0x14; +- o_hdr_pe32p.code_sz = total_sz; ++ o_hdr_pe32p.code_sz = data_size; + o_hdr_pe32p.entry_point = entry; + o_hdr.initialized_data_sz = data_size; + fwrite(&o_hdr_pe32p, sizeof(o_hdr_pe32p), 1, f); + memset(&e_hdr_pe32p, 0, sizeof(e_hdr)); + e_hdr_pe32p.section_align = 4096; + e_hdr_pe32p.file_align = 512; +- e_hdr_pe32p.image_sz = total_sz; +- e_hdr_pe32p.headers_sz = 512; ++ e_hdr_pe32p.image_sz = hdr_sz + so_size; ++ e_hdr_pe32p.headers_sz = hdr_sz; + e_hdr_pe32p.subsystem = IMAGE_SUBSYSTEM_EFI_APPLICATION; + e_hdr_pe32p.rva_and_sizes_nr = sizeof(e_hdr_pe32p.data_directory) / sizeof(__uint64_t); + fwrite(&e_hdr_pe32p, sizeof(e_hdr_pe32p), 1, f); +@@ -136,8 +130,10 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + + memset(&t_sec, 0, sizeof(t_sec)); + strcpy((char *)t_sec.name, ".text"); +- t_sec.virtual_sz = total_sz; +- t_sec.raw_data_sz = total_sz; ++ t_sec.virtual_sz = data_size; ++ t_sec.virtual_address = hdr_sz; ++ t_sec.raw_data_sz = t_sec.virtual_sz; ++ t_sec.raw_data = t_sec.virtual_address; + t_sec.characteristics = IMAGE_SCN_CNT_CODE | + IMAGE_SCN_ALIGN_16BYTES | IMAGE_SCN_MEM_EXECUTE | + IMAGE_SCN_MEM_READ; +@@ -163,6 +159,16 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + fwrite(&c_rel, sizeof(c_rel), 1, f); + fwrite(&dummy, sizeof(dummy), 1, f); + ++ /* ++ * Add some padding to align the ELF as needed ++ */ ++ if (ftell(f) > t_sec.virtual_address) { ++ // A fseek that rewind would be a bug hard to track ++ fprintf(stderr, "PE+ headers are too large.\n"); ++ exit(EXIT_FAILURE); ++ } ++ ++ fseek(f, t_sec.virtual_address, SEEK_SET); + } + + static void usage(char *progname) +There is no need to have a relocation section that nothing points at. +The image is still seen as relocatable as long as the Characteristics of +the FileHeader do not say otherwise. + +Moreover, the field base_relocation_table wasn't initialized properly +leading to unpredictable bugs. + +Signed-off-by: Celelibi <celelibi at gmail.com> +--- + +I'm not 100% positive about the uselessness of the relocation section. However: +1) it works on my real hardware; +2) OVMF doesn't check the section headers at all; +3) all the docs I could find say that the section names are arbitrary; +4) the only way to make the relocation actually happen is by setting the +base_relocation_table field of the extra headers to point to this section; +5) The right way to indicate the image is not relocatable would be by setting +the characteristics IMAGE_FILE_RELOCS_STRIPPED in the coff header. + +Moreover, the relocation entry cannot be inserted before the end of the headers +(512 bytes), this mean we would have to push everything a few bytes further. +And I think it's better if it can be avoided. :) + + efi/wrapper.c | 28 +++------------------------- + 1 file changed, 3 insertions(+), 25 deletions(-) + +diff --git a/efi/wrapper.c b/efi/wrapper.c +index bd2c175..9652368 100644 +--- a/efi/wrapper.c ++++ b/efi/wrapper.c +@@ -48,14 +48,12 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + { + struct optional_hdr o_hdr; + struct optional_hdr_pe32p o_hdr_pe32p; +- struct section t_sec, r_sec; ++ struct section t_sec; + struct extra_hdr e_hdr; + struct extra_hdr_pe32p e_hdr_pe32p; + struct coff_hdr c_hdr; + struct header hdr; +- struct coff_reloc c_rel; + __uint32_t total_sz = data_size; +- __uint32_t dummy = 0; + __uint32_t hdr_sz; + __uint32_t reloc_start, reloc_end; + +@@ -78,7 +76,7 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + fwrite(&hdr, sizeof(hdr), 1, f); + + memset(&c_hdr, 0, sizeof(c_hdr)); +- c_hdr.nr_sections = 2; ++ c_hdr.nr_sections = 1; + c_hdr.nr_syms = 1; + if (class == ELFCLASS32) { + c_hdr.arch = IMAGE_FILE_MACHINE_I386; +@@ -118,7 +116,7 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + o_hdr_pe32p.entry_point = entry; + o_hdr.initialized_data_sz = data_size; + fwrite(&o_hdr_pe32p, sizeof(o_hdr_pe32p), 1, f); +- memset(&e_hdr_pe32p, 0, sizeof(e_hdr)); ++ memset(&e_hdr_pe32p, 0, sizeof(e_hdr_pe32p)); + e_hdr_pe32p.section_align = 4096; + e_hdr_pe32p.file_align = 512; + e_hdr_pe32p.image_sz = hdr_sz + so_size; +@@ -140,26 +138,6 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + fwrite(&t_sec, sizeof(t_sec), 1, f); + + /* +- * Write our dummy relocation and reloc section. +- */ +- memset(&r_sec, 0, sizeof(r_sec)); +- strcpy((char *)r_sec.name, ".reloc"); +- r_sec.virtual_sz = sizeof(c_rel); +- r_sec.virtual_address = ftell(f) + sizeof(r_sec); +- r_sec.raw_data_sz = r_sec.virtual_sz; +- r_sec.raw_data = r_sec.virtual_address; +- r_sec.characteristics = IMAGE_SCN_CNT_INITIALIZED_DATA | +- IMAGE_SCN_ALIGN_1BYTES | IMAGE_SCN_MEM_DISCARDABLE | +- IMAGE_SCN_MEM_READ; +- fwrite(&r_sec, sizeof(r_sec), 1, f); +- +- memset(&c_rel, 0, sizeof(c_rel)); +- c_rel.virtual_address = ftell(f) + sizeof(c_rel); +- c_rel.symtab_index = 10; +- fwrite(&c_rel, sizeof(c_rel), 1, f); +- fwrite(&dummy, sizeof(dummy), 1, f); +- +- /* + * Add some padding to align the ELF as needed + */ + if (ftell(f) > t_sec.virtual_address) { +PE headers code_sz and image_sz indicate more or less, the size of the +file and the size of the in-memory image. They are now given the right +value. + +In the ELF format, only the program headers are reliable to determine +the actually needed part of the file and the in-memory size. + +The .bss section should always be marked as NOLOAD for ld since its +content shouldn't be included into the binary file. + +Signed-off-by: Celelibi <celelibi at gmail.com> +--- + +Again, I'm not 100% positive about the semantics of NOLOAD in a linker script. +However I found this make things work better. +Actually the file core/fs/fs.o have a .bss16 section that is not empty. If I +understood correctly, only .bss can be empty in a .o. Thus ld generates the +zeros that belong to that section in the .o. Then, when merging the section +.bss16 into the .bss of syslinux.so, ld is forced to generate ALL the zeros +that belong to the .bss section. Marking this section as NOLOAD make ld to +ignore its content but still produce a PT_LOAD program header with the right +memory size, as needed for the bss. + + efi/i386/syslinux.ld | 4 +- + efi/wrapper.c | 138 +++++++++++++++---------------------------------- + efi/x86_64/syslinux.ld | 4 +- + 3 files changed, 45 insertions(+), 101 deletions(-) + +diff --git a/efi/i386/syslinux.ld b/efi/i386/syslinux.ld +index 523a9b9..bab3fc7 100644 +--- a/efi/i386/syslinux.ld ++++ b/efi/i386/syslinux.ld +@@ -136,7 +136,7 @@ SECTIONS + *(.strtab) + } + +- .bss : { ++ .bss (NOLOAD) : { + /* the EFI loader doesn't seem to like a .bss section, + so we stick it all into .data: */ + __bss_start = .; +@@ -153,7 +153,7 @@ SECTIONS + __bss_dwords = (__bss_len + 3) >> 2; + + . = ALIGN(128); +- ++ + /* Very large objects which don't need to be zeroed */ + + .hugebss : { +diff --git a/efi/wrapper.c b/efi/wrapper.c +index 9652368..a5247ae 100644 +--- a/efi/wrapper.c ++++ b/efi/wrapper.c +@@ -35,7 +35,7 @@ typedef Elf64_Addr Elf_Addr; + #endif + + /* +- * 'so_size' is the file size of the ELF shared object. ++ * 'so_memsz' is the size of the ELF shared object once loaded. + * 'data_size' is the size of initialised data in the shared object. + * 'class' dictates how the header is written + * For 32bit machines (class == ELFCLASS32), the optional +@@ -44,7 +44,7 @@ typedef Elf64_Addr Elf_Addr; + * header includes PE32+header fields + */ + static void write_header(FILE *f, __uint32_t entry, size_t data_size, +- __uint32_t so_size, __uint8_t class) ++ __uint32_t so_memsz, __uint8_t class) + { + struct optional_hdr o_hdr; + struct optional_hdr_pe32p o_hdr_pe32p; +@@ -96,7 +96,7 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + memset(&e_hdr, 0, sizeof(e_hdr)); + e_hdr.section_align = 4096; + e_hdr.file_align = 512; +- e_hdr.image_sz = hdr_sz + so_size; ++ e_hdr.image_sz = hdr_sz + so_memsz; + e_hdr.headers_sz = hdr_sz; + e_hdr.subsystem = IMAGE_SUBSYSTEM_EFI_APPLICATION; + e_hdr.rva_and_sizes_nr = sizeof(e_hdr.data_directory) / sizeof(__uint64_t); +@@ -119,7 +119,7 @@ static void write_header(FILE *f, __uint32_t entry, size_t data_size, + memset(&e_hdr_pe32p, 0, sizeof(e_hdr_pe32p)); + e_hdr_pe32p.section_align = 4096; + e_hdr_pe32p.file_align = 512; +- e_hdr_pe32p.image_sz = hdr_sz + so_size; ++ e_hdr_pe32p.image_sz = hdr_sz + so_memsz; + e_hdr_pe32p.headers_sz = hdr_sz; + e_hdr_pe32p.subsystem = IMAGE_SUBSYSTEM_EFI_APPLICATION; + e_hdr_pe32p.rva_and_sizes_nr = sizeof(e_hdr_pe32p.data_directory) / sizeof(__uint64_t); +@@ -157,17 +157,16 @@ static void usage(char *progname) + + int main(int argc, char **argv) + { +- struct stat st; + Elf32_Ehdr e32_hdr; + Elf64_Ehdr e64_hdr; + __uint32_t entry; + __uint8_t class; +- __uint64_t shoff; +- __uint16_t shnum, shentsize, shstrndx; ++ __uint64_t phoff = 0; ++ __uint16_t phnum = 0, phentsize = 0; + unsigned char *id; + FILE *f_in, *f_out; + void *buf; +- size_t datasz, rv; ++ size_t datasz, memsz, rv; + + if (argc < 3) { + usage(argv[0]); +@@ -180,11 +179,6 @@ int main(int argc, char **argv) + exit(EXIT_FAILURE); + } + +- if (stat(argv[1], &st) != 0) { +- perror("stat"); +- exit(EXIT_FAILURE); +- } +- + f_out = fopen(argv[2], "w"); + if (!f_out) { + perror("fopen"); +@@ -194,15 +188,14 @@ int main(int argc, char **argv) + /* + * Parse the ELF header and find the entry point. + */ +- fread((void *)&e32_hdr, sizeof(e32_hdr), 1, f_in); ++ fread((void *)&e32_hdr, sizeof(e32_hdr), 1, f_in); + if (e32_hdr.e_ident[EI_CLASS] == ELFCLASS32) { + id = e32_hdr.e_ident; + class = ELFCLASS32; + entry = e32_hdr.e_entry; +- shoff = e32_hdr.e_shoff; +- shnum = e32_hdr.e_shnum; +- shstrndx = e32_hdr.e_shstrndx; +- shentsize = e32_hdr.e_shentsize; ++ phoff = e32_hdr.e_phoff; ++ phnum = e32_hdr.e_phnum; ++ phentsize = e32_hdr.e_phentsize; + } + else if (e32_hdr.e_ident[EI_CLASS] == ELFCLASS64) { + /* read the header again for x86_64 +@@ -213,10 +206,9 @@ int main(int argc, char **argv) + fread((void *)&e64_hdr, sizeof(e64_hdr), 1, f_in); + id = e64_hdr.e_ident; + entry = e64_hdr.e_entry; +- shoff = e64_hdr.e_shoff; +- shnum = e64_hdr.e_shnum; +- shstrndx = e64_hdr.e_shstrndx; +- shentsize = e64_hdr.e_shentsize; ++ phoff = e64_hdr.e_phoff; ++ phnum = e64_hdr.e_phnum; ++ phentsize = e64_hdr.e_phentsize; + } else { + fprintf(stderr, "Unsupported architecture\n"); + exit(EXIT_FAILURE); +@@ -230,98 +222,47 @@ int main(int argc, char **argv) + exit(EXIT_FAILURE); + } + +- if (!shoff || !shnum || (shstrndx == SHN_UNDEF)) { +- fprintf(stderr, "Cannot find section table\n"); ++ if (!phoff || !phnum) { ++ fprintf(stderr, "Cannot find segment table\n"); + exit(EXIT_FAILURE); + } + + /* +- * Find the beginning of the .bss section. Everything preceding +- * it is copied verbatim to the output file. ++ * Find the LOAD program header. Everything in this segment ++ * is copied verbatim to the output file. ++ * Although there may be several LOAD program headers, only ++ * one is currently copied. + */ + if (e32_hdr.e_ident[EI_CLASS] == ELFCLASS32) { +- const char *shstrtab, *name; +- Elf32_Shdr shdr; ++ Elf32_Phdr phdr; + int i; +- void *strtab; +- +- fseek(f_in, shoff, SEEK_SET); +- +- /* First find the strtab section */ +- fseek(f_in, shstrndx * shentsize, SEEK_CUR); +- fread(&shdr, sizeof(shdr), 1, f_in); + +- strtab = malloc(shdr.sh_size); +- if (!strtab) { +- fprintf(stderr, "Failed to malloc strtab\n"); +- exit(EXIT_FAILURE); +- } +- +- fseek(f_in, shdr.sh_offset, SEEK_SET); +- fread(strtab, shdr.sh_size, 1, f_in); +- +- /* Now search for the .bss section */ +- fseek(f_in, shoff, SEEK_SET); +- for (i = 0; i < shnum; i++) { +- rv = fread(&shdr, sizeof(shdr), 1, f_in); +- if (!rv) { +- fprintf(stderr, "Failed to read section table\n"); +- exit(EXIT_FAILURE); +- } ++ /* Find the first LOAD program header */ ++ for (i = 0; i < phnum; i++) { ++ fseek(f_in, phoff + i * phentsize, SEEK_SET); ++ fread(&phdr, sizeof(phdr), 1, f_in); + +- name = strtab + shdr.sh_name; +- if (!strcmp(name, ".bss")) ++ if (phdr.p_type == PT_LOAD) + break; + } + +- if (i == shnum) { +- fprintf(stderr, "Failed to find .bss section\n"); +- exit(EXIT_FAILURE); +- } +- +- datasz = shdr.sh_offset; +- } +- else if (e32_hdr.e_ident[EI_CLASS] == ELFCLASS64) { +- const char *shstrtab, *name; +- Elf64_Shdr shdr; ++ datasz = phdr.p_filesz; ++ memsz = phdr.p_memsz; ++ } else if (e32_hdr.e_ident[EI_CLASS] == ELFCLASS64) { ++ Elf64_Phdr phdr; + int i; +- void *strtab; +- +- fseek(f_in, shoff, SEEK_SET); + +- /* First find the strtab section */ +- fseek(f_in, shstrndx * shentsize, SEEK_CUR); +- fread(&shdr, sizeof(shdr), 1, f_in); +- +- strtab = malloc(shdr.sh_size); +- if (!strtab) { +- fprintf(stderr, "Failed to malloc strtab\n"); +- exit(EXIT_FAILURE); +- } ++ /* Find the first LOAD program header */ ++ for (i = 0; i < phnum; i++) { ++ fseek(f_in, phoff + i * phentsize, SEEK_SET); ++ fread(&phdr, sizeof(phdr), 1, f_in); + +- fseek(f_in, shdr.sh_offset, SEEK_SET); +- fread(strtab, shdr.sh_size, 1, f_in); +- +- /* Now search for the .bss section */ +- fseek(f_in, shoff, SEEK_SET); +- for (i = 0; i < shnum; i++) { +- rv = fread(&shdr, sizeof(shdr), 1, f_in); +- if (!rv) { +- fprintf(stderr, "Failed to read section table\n"); +- exit(EXIT_FAILURE); +- } +- +- name = strtab + shdr.sh_name; +- if (!strcmp(name, ".bss")) ++ if (phdr.p_type == PT_LOAD) + break; + } + +- if (i == shnum) { +- fprintf(stderr, "Failed to find .bss section\n"); +- exit(EXIT_FAILURE); +- } +- +- datasz = shdr.sh_offset; ++ datasz = phdr.p_filesz; ++ memsz = phdr.p_memsz; + } + + buf = malloc(datasz); +@@ -330,7 +271,7 @@ int main(int argc, char **argv) + exit(EXIT_FAILURE); + } + +- write_header(f_out, entry, datasz, st.st_size, class); ++ write_header(f_out, entry, datasz, memsz, class); + + /* Write out the entire ELF shared object */ + rewind(f_in); +@@ -341,5 +282,8 @@ int main(int argc, char **argv) + } + + fwrite(buf, datasz, rv, f_out); ++ free(buf); ++ fclose(f_out); ++ fclose(f_in); + return 0; + } +diff --git a/efi/x86_64/syslinux.ld b/efi/x86_64/syslinux.ld +index 95160bd..450641c 100644 +--- a/efi/x86_64/syslinux.ld ++++ b/efi/x86_64/syslinux.ld +@@ -136,7 +136,7 @@ SECTIONS + *(.strtab) + } + +- .bss : { ++ .bss (NOLOAD) : { + /* the EFI loader doesn't seem to like a .bss section, + so we stick it all into .data: */ + __bss_start = .; +@@ -153,7 +153,7 @@ SECTIONS + __bss_dwords = (__bss_len + 3) >> 2; + + . = ALIGN(128); +- ++ + /* Very large objects which don't need to be zeroed */ + + .hugebss : { |