From 4940bb10515316791f1940a59bfeaeebee35ec87 Mon Sep 17 00:00:00 2001 From: "kenneth.liu" Date: Sat, 22 Feb 2025 13:20:11 +0800 Subject: [PATCH] components: libc: fix pointer-to-integer cast warnings and address truncation [Problem Description] 1. When enabling RT_USING_MODULE=y, compilation warnings occur: dlelf.c:386:27: warning: cast from pointer to integer of different size dlelf.c:398:25: warning: cast from pointer to integer of different size dlelf.c:408:24: warning: cast from pointer to integer of different size 2. On RV64 architectures (e.g. Sophgo SG2042 with RISC-V Sv39 and 40-bit physical addressing), dlsym may fail when accessing addresses beyond 32-bit range. [Root Cause] In dlmodule_load_relocated_object() and dlmodule_symbol_find(), pointer is cast to rt_uint32_t which truncates: | rt_ubase_t rodata_addr = (rt_uint32_t)ptr; This causes: - Warnings on 64-bit systems (pointer width > 32-bit) - Actual address truncation on RV64 when physical address exceeds 32-bit [Solution] Replace rt_uint32_t with architecture-adaptive rt_ubase_t: | rt_ubase_t rodata_addr = (rt_ubase_t)ptr; The rt_ubase_t is defined in include/rttypes.h as: | #ifdef ARCH_CPU_64BIT | typedef rt_uint64_t rt_ubase_t; | #else | typedef rt_uint32_t rt_ubase_t; | #endif This ensures correct width casting for both 32/64-bit architectures. Signed-off-by: Liu Gui --- components/libc/posix/libdl/dlelf.c | 10 +++++----- components/libc/posix/libdl/dlmodule.c | 6 +++--- components/libc/posix/libdl/dlmodule.h | 2 +- 3 files changed, 9 insertions(+), 9 deletions(-) diff --git a/components/libc/posix/libdl/dlelf.c b/components/libc/posix/libdl/dlelf.c index 9e8f1c6b2d..4fc89e5aaa 100644 --- a/components/libc/posix/libdl/dlelf.c +++ b/components/libc/posix/libdl/dlelf.c @@ -383,9 +383,9 @@ rt_err_t dlmodule_load_relocated_object(struct rt_dlmodule* module, void *module rt_memcpy(ptr, (rt_uint8_t *)elf_module + shdr[index].sh_offset, shdr[index].sh_size); - rodata_addr = (rt_uint32_t)ptr; + rodata_addr = (rt_ubase_t)ptr; LOG_D("load rodata 0x%x, size %d, rodata 0x%x", ptr, - shdr[index].sh_size, *(rt_uint32_t *)data_addr); + shdr[index].sh_size, *(rt_ubase_t *)rodata_addr); ptr += shdr[index].sh_size; } @@ -395,9 +395,9 @@ rt_err_t dlmodule_load_relocated_object(struct rt_dlmodule* module, void *module rt_memcpy(ptr, (rt_uint8_t *)elf_module + shdr[index].sh_offset, shdr[index].sh_size); - data_addr = (rt_uint32_t)ptr; + data_addr = (rt_ubase_t)ptr; LOG_D("load data 0x%x, size %d, data 0x%x", ptr, - shdr[index].sh_size, *(rt_uint32_t *)data_addr); + shdr[index].sh_size, *(rt_ubase_t *)data_addr); ptr += shdr[index].sh_size; } @@ -405,7 +405,7 @@ rt_err_t dlmodule_load_relocated_object(struct rt_dlmodule* module, void *module if (IS_NOPROG(shdr[index]) && IS_AW(shdr[index])) { rt_memset(ptr, 0, shdr[index].sh_size); - bss_addr = (rt_uint32_t)ptr; + bss_addr = (rt_ubase_t)ptr; LOG_D("load bss 0x%x, size %d", ptr, shdr[index].sh_size); } } diff --git a/components/libc/posix/libdl/dlmodule.c b/components/libc/posix/libdl/dlmodule.c index 17aca0b2da..eee45d0843 100644 --- a/components/libc/posix/libdl/dlmodule.c +++ b/components/libc/posix/libdl/dlmodule.c @@ -837,10 +837,10 @@ void dlmodule_exit(int ret_code) * @brief search for a symbol by its name in the kernel symbol table. * * @param sym_str the symbol name string. - * @return rt_uint32_t On success, it returns the address of the symbol. + * @return rt_ubase_t On success, it returns the address of the symbol. * Otherwise, it returns 0 (indicating the symbol was not found). */ -rt_uint32_t dlmodule_symbol_find(const char *sym_str) +rt_ubase_t dlmodule_symbol_find(const char *sym_str) { /* find in kernel symbol table */ struct rt_module_symtab *index; @@ -848,7 +848,7 @@ rt_uint32_t dlmodule_symbol_find(const char *sym_str) for (index = _rt_module_symtab_begin; index != _rt_module_symtab_end; index ++) { if (rt_strcmp(index->name, sym_str) == 0) - return (rt_uint32_t)index->addr; + return (rt_ubase_t)index->addr; } return 0; diff --git a/components/libc/posix/libdl/dlmodule.h b/components/libc/posix/libdl/dlmodule.h index 62a0cdd5d3..75ca325800 100644 --- a/components/libc/posix/libdl/dlmodule.h +++ b/components/libc/posix/libdl/dlmodule.h @@ -82,6 +82,6 @@ void dlmodule_exit(int ret_code); struct rt_dlmodule *dlmodule_find(const char *name); -rt_uint32_t dlmodule_symbol_find(const char *sym_str); +rt_ubase_t dlmodule_symbol_find(const char *sym_str); #endif