Fix the linker scripts to generate three distinct PT_LOAD segments with correct permissions instead of combining .rodata with .data.
Before this fix, the linker auto-generated only two PT_LOAD segments: 1. Text segment (PF_R|PF_X) 2. Data segment (PF_R|PF_W) - containing .rodata, .data, .bss, etc. This caused .rodata to be mapped with write permissions when pbl_mmu_setup_from_elf() set up MMU permissions based on ELF segments, defeating the W^X protection that commit d9ccb0cf14 intended to provide. With explicit PHDRS directives, we now generate three segments: 1. text segment (PF_R|PF_X): .text and related code sections 2. rodata segment (PF_R): .rodata and unwind tables 3. data segment (PF_R|PF_W): .data, .bss, and related sections This ensures pbl_mmu_setup_from_elf() correctly maps .rodata as read-only (MAP_CACHED_RO) instead of read-write (MAP_CACHED). 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Sonnet 4.5 <[email protected]> Signed-off-by: Sascha Hauer <[email protected]> --- arch/arm/include/asm/barebox.lds.h | 2 +- arch/arm/lib32/barebox.lds.S | 34 ++++++++++++++++++++++------------ arch/arm/lib64/barebox.lds.S | 29 +++++++++++++++++++---------- arch/riscv/lib/barebox.lds.S | 1 + 4 files changed, 43 insertions(+), 23 deletions(-) diff --git a/arch/arm/include/asm/barebox.lds.h b/arch/arm/include/asm/barebox.lds.h index 72aabe155b5c9e8b9159c7da6c6f0fa1f7b93375..7d1811645762a2ce1f58b7d86bed188a93fdb711 100644 --- a/arch/arm/include/asm/barebox.lds.h +++ b/arch/arm/include/asm/barebox.lds.h @@ -16,7 +16,7 @@ #define BAREBOX_RELOCATION_TABLE \ .rel_dyn_start : { *(.__rel_dyn_start) } \ - .BAREBOX_RELOCATION_TYPE.dyn : { *(.BAREBOX_RELOCATION_TYPE*) } \ + .BAREBOX_RELOCATION_TYPE.dyn : { *(.BAREBOX_RELOCATION_TYPE*) } \ .rel_dyn_end : { *(.__rel_dyn_end) } \ .__dynsym_start : { *(.__dynsym_start) } \ .dynsym : { *(.dynsym) } \ diff --git a/arch/arm/lib32/barebox.lds.S b/arch/arm/lib32/barebox.lds.S index 17e0970ba4989e5213ed38ea5ff87bdf5bfa2740..e84118ee2f43b07bd82fcd9936398847d0a3b42f 100644 --- a/arch/arm/lib32/barebox.lds.S +++ b/arch/arm/lib32/barebox.lds.S @@ -7,14 +7,23 @@ OUTPUT_FORMAT(BAREBOX_OUTPUT_FORMAT) OUTPUT_ARCH(BAREBOX_OUTPUT_ARCH) ENTRY(start) + +PHDRS +{ + text PT_LOAD FLAGS(5); /* PF_R | PF_X */ + rodata PT_LOAD FLAGS(4); /* PF_R */ + data PT_LOAD FLAGS(6); /* PF_R | PF_W */ + dynamic PT_DYNAMIC FLAGS(6); /* PF_R | PF_W */ +} + SECTIONS { . = 0x0; - .image_start : { *(.__image_start) } + .image_start : { *(.__image_start) } :text . = ALIGN(4); - ._text : { *(._text) } + ._text : { *(._text) } :text .text : { _stext = .; @@ -31,7 +40,7 @@ SECTIONS KEEP(*(.text_inplace_exceptions*)) __inplace_exceptions_stop = .; *(.text*) - } + } :text BAREBOX_BARE_INIT_SIZE . = ALIGN(4096); @@ -39,7 +48,7 @@ SECTIONS .rodata : { *(.rodata*) RO_DATA_SECTION - } + } :rodata #ifdef CONFIG_ARM_UNWIND /* @@ -50,20 +59,21 @@ SECTIONS __start_unwind_idx = .; *(.ARM.exidx*) __stop_unwind_idx = .; - } + } :rodata .ARM.unwind_tab : { __start_unwind_tab = .; *(.ARM.extab*) __stop_unwind_tab = .; - } + } :rodata #endif . = ALIGN(4096); __end_rodata = .; _etext = .; _sdata = .; - . = ALIGN(4); - .data : { *(.data*) } + .data : { *(.data*) } :data + + .dynamic : { *(.dynamic) } :data :dynamic . = .; @@ -73,12 +83,12 @@ SECTIONS BAREBOX_EFI_RUNTIME - .image_end : { *(.__image_end) } + .image_end : { *(.__image_end) } :data . = ALIGN(4); - .__bss_start : { *(.__bss_start) } - .bss : { *(.bss*) } - .__bss_stop : { *(.__bss_stop) } + .__bss_start : { *(.__bss_start) } :data + .bss : { *(.bss*) } :data + .__bss_stop : { *(.__bss_stop) } :data #ifdef CONFIG_ARM_SECURE_MONITOR . = ALIGN(16); diff --git a/arch/arm/lib64/barebox.lds.S b/arch/arm/lib64/barebox.lds.S index 5ee5fbc3741e1f7644c00f9b37c0903c27704a3e..0278347e78c70318a03eddda77510e38d3e9f026 100644 --- a/arch/arm/lib64/barebox.lds.S +++ b/arch/arm/lib64/barebox.lds.S @@ -6,14 +6,23 @@ OUTPUT_FORMAT(BAREBOX_OUTPUT_FORMAT) OUTPUT_ARCH(BAREBOX_OUTPUT_ARCH) ENTRY(start) + +PHDRS +{ + text PT_LOAD FLAGS(5); /* PF_R | PF_X */ + rodata PT_LOAD FLAGS(4); /* PF_R */ + data PT_LOAD FLAGS(6); /* PF_R | PF_W */ + dynamic PT_DYNAMIC FLAGS(6); /* PF_R | PF_W */ +} + SECTIONS { . = 0x0; - .image_start : { *(.__image_start) } + .image_start : { *(.__image_start) } :text . = ALIGN(4); - ._text : { *(._text) } + ._text : { *(._text) } :text .text : { _stext = .; @@ -22,7 +31,7 @@ SECTIONS *(.text_bare_init*) __bare_init_end = .; *(.text*) - } + } :text BAREBOX_BARE_INIT_SIZE . = ALIGN(4096); @@ -30,7 +39,7 @@ SECTIONS .rodata : { *(.rodata*) RO_DATA_SECTION - } + } :rodata . = ALIGN(4096); @@ -38,20 +47,20 @@ SECTIONS _etext = .; _sdata = .; - .data : { *(.data*) } + .data : { *(.data*) } :data - BAREBOX_RELOCATION_TABLE + .dynamic : { *(.dynamic) } :data :dynamic _edata = .; BAREBOX_EFI_RUNTIME - .image_end : { *(.__image_end) } + .image_end : { *(.__image_end) } :data . = ALIGN(4); - .__bss_start : { *(.__bss_start) } - .bss : { *(.bss*) } - .__bss_stop : { *(.__bss_stop) } + .__bss_start : { *(.__bss_start) } :data + .bss : { *(.bss*) } :data + .__bss_stop : { *(.__bss_stop) } :data _end = .; _barebox_image_size = __bss_start; } diff --git a/arch/riscv/lib/barebox.lds.S b/arch/riscv/lib/barebox.lds.S index 03b3a967193cfee1c67b96632cf972a553e8bec4..38376befe9a82ead2152f8c7fc581eb5bb35fab4 100644 --- a/arch/riscv/lib/barebox.lds.S +++ b/arch/riscv/lib/barebox.lds.S @@ -16,6 +16,7 @@ OUTPUT_ARCH(BAREBOX_OUTPUT_ARCH) ENTRY(start) OUTPUT_FORMAT(BAREBOX_OUTPUT_FORMAT) + SECTIONS { . = 0x0; -- 2.47.3
