From fa5750521e0a4efbc1af05223da9c4bbd6c21c83 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 15 Sep 2023 17:16:30 +0000 Subject: x86/boot: Drop PE/COFF .reloc section Ancient buggy EFI loaders may have required a .reloc section to be present at some point in time, but this has not been true for a long time so the .reloc section can just be dropped. Signed-off-by: Ard Biesheuvel Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20230915171623.655440-16-ardb@google.com --- arch/x86/boot/header.S | 20 -------------------- arch/x86/boot/setup.ld | 4 ++-- arch/x86/boot/tools/build.c | 34 +++++----------------------------- 3 files changed, 7 insertions(+), 51 deletions(-) (limited to 'arch/x86/boot') diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S index 2b07bc596c39..9e9641e220a7 100644 --- a/arch/x86/boot/header.S +++ b/arch/x86/boot/header.S @@ -155,26 +155,6 @@ section_table: IMAGE_SCN_MEM_READ | \ IMAGE_SCN_MEM_EXECUTE # Characteristics - # - # The EFI application loader requires a relocation section - # because EFI applications must be relocatable. The .reloc - # offset & size fields are filled in by build.c. - # - .ascii ".reloc" - .byte 0 - .byte 0 - .long 0 - .long 0 - .long 0 # SizeOfRawData - .long 0 # PointerToRawData - .long 0 # PointerToRelocations - .long 0 # PointerToLineNumbers - .word 0 # NumberOfRelocations - .word 0 # NumberOfLineNumbers - .long IMAGE_SCN_CNT_INITIALIZED_DATA | \ - IMAGE_SCN_MEM_READ | \ - IMAGE_SCN_MEM_DISCARDABLE # Characteristics - #ifdef CONFIG_EFI_MIXED # # The offset & size fields are filled in by build.c. diff --git a/arch/x86/boot/setup.ld b/arch/x86/boot/setup.ld index 9bd5c1ada599..6d389499565c 100644 --- a/arch/x86/boot/setup.ld +++ b/arch/x86/boot/setup.ld @@ -40,8 +40,8 @@ SECTIONS setup_sig = .; LONG(0x5a5aaa55) - /* Reserve some extra space for the reloc and compat sections */ - setup_size = ALIGN(ABSOLUTE(.) + 64, 512); + /* Reserve some extra space for the compat section */ + setup_size = ALIGN(ABSOLUTE(.) + 32, 512); setup_sects = ABSOLUTE(setup_size / 512); } diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c index 9712f27e32c1..faccff9743a3 100644 --- a/arch/x86/boot/tools/build.c +++ b/arch/x86/boot/tools/build.c @@ -47,7 +47,6 @@ typedef unsigned int u32; /* This must be large enough to hold the entire setup */ u8 buf[SETUP_SECT_MAX*512]; -#define PECOFF_RELOC_RESERVE 0x20 #define PECOFF_COMPAT_RESERVE 0x20 static unsigned long efi32_pe_entry; @@ -180,24 +179,13 @@ static void update_pecoff_section_header(char *section_name, u32 offset, u32 siz update_pecoff_section_header_fields(section_name, offset, size, size, offset); } -static void update_pecoff_setup_and_reloc(unsigned int size) +static void update_pecoff_setup(unsigned int size) { u32 setup_offset = 0x200; - u32 reloc_offset = size - PECOFF_RELOC_RESERVE - PECOFF_COMPAT_RESERVE; -#ifdef CONFIG_EFI_MIXED - u32 compat_offset = reloc_offset + PECOFF_RELOC_RESERVE; -#endif - u32 setup_size = reloc_offset - setup_offset; + u32 compat_offset = size - PECOFF_COMPAT_RESERVE; + u32 setup_size = compat_offset - setup_offset; update_pecoff_section_header(".setup", setup_offset, setup_size); - update_pecoff_section_header(".reloc", reloc_offset, PECOFF_RELOC_RESERVE); - - /* - * Modify .reloc section contents with a single entry. The - * relocation is applied to offset 10 of the relocation section. - */ - put_unaligned_le32(reloc_offset + 10, &buf[reloc_offset]); - put_unaligned_le32(10, &buf[reloc_offset + 4]); #ifdef CONFIG_EFI_MIXED update_pecoff_section_header(".compat", compat_offset, PECOFF_COMPAT_RESERVE); @@ -214,21 +202,10 @@ static void update_pecoff_setup_and_reloc(unsigned int size) #endif } -static int reserve_pecoff_reloc_section(int c) -{ - /* Reserve 0x20 bytes for .reloc section */ - memset(buf+c, 0, PECOFF_RELOC_RESERVE); - return PECOFF_RELOC_RESERVE; -} - #else -static inline void update_pecoff_setup_and_reloc(unsigned int size) {} +static inline void update_pecoff_setup(unsigned int size) {} -static inline int reserve_pecoff_reloc_section(int c) -{ - return 0; -} #endif /* CONFIG_EFI_STUB */ static int reserve_pecoff_compat_section(int c) @@ -307,7 +284,6 @@ int main(int argc, char ** argv) fclose(file); c += reserve_pecoff_compat_section(c); - c += reserve_pecoff_reloc_section(c); /* Pad unused space with zeros */ setup_sectors = (c + 511) / 512; @@ -316,7 +292,7 @@ int main(int argc, char ** argv) i = setup_sectors*512; memset(buf+c, 0, i-c); - update_pecoff_setup_and_reloc(i); + update_pecoff_setup(i); /* Open and stat the kernel file */ fd = open(argv[2], O_RDONLY); -- cgit v1.2.3