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 | 14 +++++++------- arch/arm/lib/pbl.lds.S | 2 +- arch/arm/lib32/barebox.lds.S | 35 +++++++++++++++++++++++------------ arch/arm/lib64/barebox.lds.S | 31 +++++++++++++++++++++---------- 4 files changed, 52 insertions(+), 30 deletions(-) diff --git a/arch/arm/include/asm/barebox.lds.h b/arch/arm/include/asm/barebox.lds.h index 72aabe155b5c9e8b9159c7da6c6f0fa1f7b93375..a3ccea91196ccce71c54483c5e1ad5caeb3c1d32 100644 --- a/arch/arm/include/asm/barebox.lds.h +++ b/arch/arm/include/asm/barebox.lds.h @@ -14,13 +14,13 @@ #define BAREBOX_RELOCATION_TYPE rela #endif -#define BAREBOX_RELOCATION_TABLE \ - .rel_dyn_start : { *(.__rel_dyn_start) } \ - .BAREBOX_RELOCATION_TYPE.dyn : { *(.BAREBOX_RELOCATION_TYPE*) } \ - .rel_dyn_end : { *(.__rel_dyn_end) } \ - .__dynsym_start : { *(.__dynsym_start) } \ - .dynsym : { *(.dynsym) } \ - .__dynsym_end : { *(.__dynsym_end) } +#define BAREBOX_RELOCATION_TABLE(PHDR) \ + .rel_dyn_start : { *(.__rel_dyn_start) } PHDR \ + .BAREBOX_RELOCATION_TYPE.dyn : { *(.BAREBOX_RELOCATION_TYPE*) } PHDR \ + .rel_dyn_end : { *(.__rel_dyn_end) } PHDR \ + .__dynsym_start : { *(.__dynsym_start) } PHDR \ + .dynsym : { *(.dynsym) } PHDR \ + .__dynsym_end : { *(.__dynsym_end) } PHDR #include <asm-generic/barebox.lds.h> diff --git a/arch/arm/lib/pbl.lds.S b/arch/arm/lib/pbl.lds.S index 53b21084cff2e3d916cd37485281f2f78166c37d..98e25a543525e2bc16b8d10ec24c2ba6b8cbec90 100644 --- a/arch/arm/lib/pbl.lds.S +++ b/arch/arm/lib/pbl.lds.S @@ -95,7 +95,7 @@ SECTIONS } __shasum_end = .; - BAREBOX_RELOCATION_TABLE + BAREBOX_RELOCATION_TABLE() pbl_code_size = .; diff --git a/arch/arm/lib32/barebox.lds.S b/arch/arm/lib32/barebox.lds.S index 9b2b65e2f17d62d5134fc367621cce733dcea06a..c91c101d6aa5c2a0fcbf79a151a4234d924b3881 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 /* @@ -50,12 +59,12 @@ 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 = .; @@ -65,19 +74,21 @@ SECTIONS . = ALIGN(4); .data : { *(.data*) CONSTRUCTORS - } + } :data + + .dynamic : { *(.dynamic) } :data :dynamic . = .; - BAREBOX_RELOCATION_TABLE + BAREBOX_RELOCATION_TABLE(:data) _edata = .; - .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 e2f1164c47f7e5d300028d112a6e90e2fa368c65..603e0ab77490d3221fbfd3341250e6dcae840d91 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); @@ -38,18 +47,20 @@ SECTIONS _etext = .; _sdata = .; - .data : { *(.data*) } + .data : { *(.data*) } :data + + .dynamic : { *(.dynamic) } :data :dynamic - BAREBOX_RELOCATION_TABLE + BAREBOX_RELOCATION_TABLE(:data) _edata = .; - .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; } -- 2.47.3
