diff options
Diffstat (limited to 'kernels/linux-libre-xen/0013-efistub-fix.patch')
-rw-r--r-- | kernels/linux-libre-xen/0013-efistub-fix.patch | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/kernels/linux-libre-xen/0013-efistub-fix.patch b/kernels/linux-libre-xen/0013-efistub-fix.patch new file mode 100644 index 000000000..a2da3b63a --- /dev/null +++ b/kernels/linux-libre-xen/0013-efistub-fix.patch @@ -0,0 +1,177 @@ +From c7fb93ec51d462ec3540a729ba446663c26a0505 Mon Sep 17 00:00:00 2001 +From: Michael Brown <mbrown@fensystems.co.uk> +Date: Thu, 10 Jul 2014 12:26:20 +0100 +Subject: x86/efi: Include a .bss section within the PE/COFF headers +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +The PE/COFF headers currently describe only the initialised-data +portions of the image, and result in no space being allocated for the +uninitialised-data portions. Consequently, the EFI boot stub will end +up overwriting unexpected areas of memory, with unpredictable results. + +Fix by including a .bss section in the PE/COFF headers (functionally +equivalent to the init_size field in the bzImage header). + +Signed-off-by: Michael Brown <mbrown@fensystems.co.uk> +Cc: Thomas Bächler <thomas@archlinux.org> +Cc: Josh Boyer <jwboyer@fedoraproject.org> +Cc: <stable@vger.kernel.org> +Signed-off-by: Matt Fleming <matt.fleming@intel.com> + +diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S +index 84c2234..7a6d43a 100644 +--- a/arch/x86/boot/header.S ++++ b/arch/x86/boot/header.S +@@ -91,10 +91,9 @@ bs_die: + + .section ".bsdata", "a" + bugger_off_msg: +- .ascii "Direct floppy boot is not supported. " +- .ascii "Use a boot loader program instead.\r\n" ++ .ascii "Use a boot loader.\r\n" + .ascii "\n" +- .ascii "Remove disk and press any key to reboot ...\r\n" ++ .ascii "Remove disk and press any key to reboot...\r\n" + .byte 0 + + #ifdef CONFIG_EFI_STUB +@@ -108,7 +107,7 @@ coff_header: + #else + .word 0x8664 # x86-64 + #endif +- .word 3 # nr_sections ++ .word 4 # nr_sections + .long 0 # TimeDateStamp + .long 0 # PointerToSymbolTable + .long 1 # NumberOfSymbols +@@ -250,6 +249,25 @@ section_table: + .word 0 # NumberOfLineNumbers + .long 0x60500020 # Characteristics (section flags) + ++ # ++ # The offset & size fields are filled in by build.c. ++ # ++ .ascii ".bss" ++ .byte 0 ++ .byte 0 ++ .byte 0 ++ .byte 0 ++ .long 0 ++ .long 0x0 ++ .long 0 # Size of initialized data ++ # on disk ++ .long 0x0 ++ .long 0 # PointerToRelocations ++ .long 0 # PointerToLineNumbers ++ .word 0 # NumberOfRelocations ++ .word 0 # NumberOfLineNumbers ++ .long 0xc8000080 # Characteristics (section flags) ++ + #endif /* CONFIG_EFI_STUB */ + + # Kernel attributes; used by setup. This is part 1 of the +diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c +index 1a2f212..a7661c4 100644 +--- a/arch/x86/boot/tools/build.c ++++ b/arch/x86/boot/tools/build.c +@@ -143,7 +143,7 @@ static void usage(void) + + #ifdef CONFIG_EFI_STUB + +-static void update_pecoff_section_header(char *section_name, u32 offset, u32 size) ++static void update_pecoff_section_header_fields(char *section_name, u32 vma, u32 size, u32 datasz, u32 offset) + { + unsigned int pe_header; + unsigned short num_sections; +@@ -164,10 +164,10 @@ static void update_pecoff_section_header(char *section_name, u32 offset, u32 siz + put_unaligned_le32(size, section + 0x8); + + /* section header vma field */ +- put_unaligned_le32(offset, section + 0xc); ++ put_unaligned_le32(vma, section + 0xc); + + /* section header 'size of initialised data' field */ +- put_unaligned_le32(size, section + 0x10); ++ put_unaligned_le32(datasz, section + 0x10); + + /* section header 'file offset' field */ + put_unaligned_le32(offset, section + 0x14); +@@ -179,6 +179,11 @@ static void update_pecoff_section_header(char *section_name, u32 offset, u32 siz + } + } + ++static void update_pecoff_section_header(char *section_name, u32 offset, u32 size) ++{ ++ update_pecoff_section_header_fields(section_name, offset, size, size, offset); ++} ++ + static void update_pecoff_setup_and_reloc(unsigned int size) + { + u32 setup_offset = 0x200; +@@ -203,9 +208,6 @@ static void update_pecoff_text(unsigned int text_start, unsigned int file_sz) + + pe_header = get_unaligned_le32(&buf[0x3c]); + +- /* Size of image */ +- put_unaligned_le32(file_sz, &buf[pe_header + 0x50]); +- + /* + * Size of code: Subtract the size of the first sector (512 bytes) + * which includes the header. +@@ -220,6 +222,22 @@ static void update_pecoff_text(unsigned int text_start, unsigned int file_sz) + update_pecoff_section_header(".text", text_start, text_sz); + } + ++static void update_pecoff_bss(unsigned int file_sz, unsigned int init_sz) ++{ ++ unsigned int pe_header; ++ unsigned int bss_sz = init_sz - file_sz; ++ ++ pe_header = get_unaligned_le32(&buf[0x3c]); ++ ++ /* Size of uninitialized data */ ++ put_unaligned_le32(bss_sz, &buf[pe_header + 0x24]); ++ ++ /* Size of image */ ++ put_unaligned_le32(init_sz, &buf[pe_header + 0x50]); ++ ++ update_pecoff_section_header_fields(".bss", file_sz, bss_sz, 0, 0); ++} ++ + static int reserve_pecoff_reloc_section(int c) + { + /* Reserve 0x20 bytes for .reloc section */ +@@ -259,6 +277,8 @@ static void efi_stub_entry_update(void) + static inline void update_pecoff_setup_and_reloc(unsigned int size) {} + static inline void update_pecoff_text(unsigned int text_start, + unsigned int file_sz) {} ++static inline void update_pecoff_bss(unsigned int file_sz, ++ unsigned int init_sz) {} + static inline void efi_stub_defaults(void) {} + static inline void efi_stub_entry_update(void) {} + +@@ -310,7 +330,7 @@ static void parse_zoffset(char *fname) + + int main(int argc, char ** argv) + { +- unsigned int i, sz, setup_sectors; ++ unsigned int i, sz, setup_sectors, init_sz; + int c; + u32 sys_size; + struct stat sb; +@@ -376,7 +396,9 @@ int main(int argc, char ** argv) + buf[0x1f1] = setup_sectors-1; + put_unaligned_le32(sys_size, &buf[0x1f4]); + +- update_pecoff_text(setup_sectors * 512, sz + i + ((sys_size * 16) - sz)); ++ update_pecoff_text(setup_sectors * 512, i + (sys_size * 16)); ++ init_sz = get_unaligned_le32(&buf[0x260]); ++ update_pecoff_bss(i + (sys_size * 16), init_sz); + + efi_stub_entry_update(); + +-- +cgit v0.10.1 + |