From 62570f1434160d356311e1c217537e24a4ac85cd Mon Sep 17 00:00:00 2001 From: Bin Meng Date: Tue, 16 Jan 2024 23:50:49 +0800 Subject: [PATCH] hw/elf_ops: Ignore loadable segments with zero size MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Some ELF files really do have segments of zero size, e.g.: Program Headers: Type Offset VirtAddr PhysAddr FileSiz MemSiz Flags Align RISCV_ATTRIBUT 0x00000000000025b8 0x0000000000000000 0x0000000000000000 0x000000000000003e 0x0000000000000000 R 0x1 LOAD 0x0000000000001000 0x0000000080200000 0x0000000080200000 0x00000000000001d1 0x00000000000001d1 R E 0x1000 LOAD 0x00000000000011d1 0x00000000802001d1 0x00000000802001d1 0x0000000000000e37 0x0000000000000e37 RW 0x1000 LOAD 0x0000000000000120 0x0000000000000000 0x0000000000000000 0x0000000000000000 0x0000000000000000 0x1000 The current logic does not check for this condition, resulting in the incorrect assignment of 'lowaddr' as zero. There is already a piece of codes inside the segment traversal loop that checks for zero-sized loadable segments for not creating empty ROM blobs. Let's move this check to the beginning of the loop to cover both scenarios. Signed-off-by: Bin Meng Reviewed-by: Richard Henderson Message-ID: <20240116155049.390301-1-bmeng@tinylab.org> Signed-off-by: Philippe Mathieu-Daudé --- include/hw/elf_ops.h | 75 +++++++++++++++++++++++++++------------------------- 1 file changed, 39 insertions(+), 36 deletions(-) diff --git a/include/hw/elf_ops.h b/include/hw/elf_ops.h index 9c35d1b9da..3e966ddd5a 100644 --- a/include/hw/elf_ops.h +++ b/include/hw/elf_ops.h @@ -427,6 +427,16 @@ static ssize_t glue(load_elf, SZ)(const char *name, int fd, file_size = ph->p_filesz; /* Size of the allocated data */ data_offset = ph->p_offset; /* Offset where the data is located */ + /* + * Some ELF files really do have segments of zero size; + * just ignore them rather than trying to set the wrong addr, + * or create empty ROM blobs, because the zero-length blob can + * falsely trigger the overlapping-ROM-blobs check. + */ + if (mem_size == 0) { + continue; + } + if (file_size > 0) { if (g_mapped_file_get_length(mapped_file) < file_size + data_offset) { @@ -530,45 +540,38 @@ static ssize_t glue(load_elf, SZ)(const char *name, int fd, *pentry = ehdr.e_entry - ph->p_vaddr + ph->p_paddr; } - /* Some ELF files really do have segments of zero size; - * just ignore them rather than trying to create empty - * ROM blobs, because the zero-length blob can falsely - * trigger the overlapping-ROM-blobs check. - */ - if (mem_size != 0) { - if (load_rom) { - g_autofree char *label = - g_strdup_printf("%s ELF program header segment %d", - name, i); - - /* - * rom_add_elf_program() takes its own reference to - * 'mapped_file'. - */ - rom_add_elf_program(label, mapped_file, data, file_size, - mem_size, addr, as); - } else { - MemTxResult res; - - res = address_space_write(as ? as : &address_space_memory, - addr, MEMTXATTRS_UNSPECIFIED, - data, file_size); + if (load_rom) { + g_autofree char *label = + g_strdup_printf("%s ELF program header segment %d", + name, i); + + /* + * rom_add_elf_program() takes its own reference to + * 'mapped_file'. + */ + rom_add_elf_program(label, mapped_file, data, file_size, + mem_size, addr, as); + } else { + MemTxResult res; + + res = address_space_write(as ? as : &address_space_memory, + addr, MEMTXATTRS_UNSPECIFIED, + data, file_size); + if (res != MEMTX_OK) { + goto fail; + } + /* + * We need to zero'ify the space that is not copied + * from file + */ + if (file_size < mem_size) { + res = address_space_set(as ? as : &address_space_memory, + addr + file_size, 0, + mem_size - file_size, + MEMTXATTRS_UNSPECIFIED); if (res != MEMTX_OK) { goto fail; } - /* - * We need to zero'ify the space that is not copied - * from file - */ - if (file_size < mem_size) { - res = address_space_set(as ? as : &address_space_memory, - addr + file_size, 0, - mem_size - file_size, - MEMTXATTRS_UNSPECIFIED); - if (res != MEMTX_OK) { - goto fail; - } - } } } -- 2.11.4.GIT