From f4393046ef647504d94b459817193c8f0684531a Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Sun, 5 Apr 2009 23:25:09 +0000 Subject: [PATCH] modprobe/insmod for 2.4: support compressed modules. by Guenter (lists AT gknw.net) function old new delta bb_init_module_24 4551 4570 +19 obj_load 786 794 +8 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 2/0 up/down: 27/0) Total: 27 bytes --- modutils/modutils-24.c | 57 ++++++++++++++++++++++++------------------ 1 file changed, 33 insertions(+), 24 deletions(-) diff --git a/modutils/modutils-24.c b/modutils/modutils-24.c index 89bc30fe5..24bc6b446 100644 --- a/modutils/modutils-24.c +++ b/modutils/modutils-24.c @@ -625,7 +625,11 @@ static unsigned long obj_load_size(struct obj_file *f); static int obj_relocate(struct obj_file *f, ElfW(Addr) base); -static struct obj_file *obj_load(int fd, int loadprogbits); +#if !LOADBITS +#define obj_load(image, image_size, loadprogbits) \ + obj_load(image, image_size) +#endif +static struct obj_file *obj_load(char *image, size_t image_size, int loadprogbits); static int obj_create_image(struct obj_file *f, char *image); @@ -3191,7 +3195,7 @@ static int obj_create_image(struct obj_file *f, char *image) /*======================================================================*/ -static struct obj_file *obj_load(int fd, int loadprogbits UNUSED_PARAM) +static struct obj_file *obj_load(char *image, size_t image_size, int loadprogbits) { #if BB_LITTLE_ENDIAN # define ELFMAG_U32 ((uint32_t)(ELFMAG0 + 0x100 * (ELFMAG1 + (0x100 * (ELFMAG2 + 0x100 * ELFMAG3))))) @@ -3210,8 +3214,9 @@ static struct obj_file *obj_load(int fd, int loadprogbits UNUSED_PARAM) f->symbol_hash = obj_elf_hash; f->load_order_search_start = &f->load_order; - xlseek(fd, 0, SEEK_SET); - xread(fd, &f->header, sizeof(f->header)); + if (image_size < sizeof(f->header)) + bb_error_msg_and_die("error while loading ELF header"); + memcpy(&f->header, image, sizeof(f->header)); if (*(uint32_t*)(&f->header.e_ident) != ELFMAG_U32) { bb_error_msg_and_die("not an ELF file"); @@ -3242,8 +3247,9 @@ static struct obj_file *obj_load(int fd, int loadprogbits UNUSED_PARAM) f->sections = xzalloc(sizeof(f->sections[0]) * (shnum + 4)); section_headers = alloca(sizeof(ElfW(Shdr)) * shnum); - xlseek(fd, f->header.e_shoff, SEEK_SET); - xread(fd, section_headers, sizeof(ElfW(Shdr)) * shnum); + if (image_size < f->header.e_shoff + sizeof(ElfW(Shdr)) * shnum) + bb_error_msg_and_die("error while loading section headers"); + memcpy(section_headers, image + f->header.e_shoff, sizeof(ElfW(Shdr)) * shnum); /* Read the section data. */ @@ -3275,8 +3281,9 @@ static struct obj_file *obj_load(int fd, int loadprogbits UNUSED_PARAM) sec->contents = NULL; if (sec->header.sh_size > 0) { sec->contents = xmalloc(sec->header.sh_size); - xlseek(fd, sec->header.sh_offset, SEEK_SET); - xread(fd, sec->contents, sec->header.sh_size); + if (image_size < (sec->header.sh_offset + sec->header.sh_size)) + bb_error_msg_and_die("error while loading section data"); + memcpy(sec->contents, image + sec->header.sh_offset, sec->header.sh_size); } break; #if SHT_RELM == SHT_REL @@ -3392,7 +3399,7 @@ static struct obj_file *obj_load(int fd, int loadprogbits UNUSED_PARAM) * kernel for the module */ -static int obj_load_progbits(int fd, struct obj_file *f, char *imagebase) +static int obj_load_progbits(char *image, size_t image_size, struct obj_file *f, char *imagebase) { ElfW(Addr) base = f->baseaddr; struct obj_section* sec; @@ -3404,12 +3411,11 @@ static int obj_load_progbits(int fd, struct obj_file *f, char *imagebase) if (sec->header.sh_size == 0) continue; sec->contents = imagebase + (sec->header.sh_addr - base); - xlseek(fd, sec->header.sh_offset, SEEK_SET); - errno = 0; /* read may be short without errno being set */ - if (full_read(fd, sec->contents, sec->header.sh_size) != sec->header.sh_size) { - bb_perror_msg("error reading ELF section data"); - return 0; + if (image_size < (sec->header.sh_offset + sec->header.sh_size)) { + bb_error_msg("error reading ELF section data"); + return 0; /* need to delete half-loaded module! */ } + memcpy(sec->contents, image + sec->header.sh_offset, sec->header.sh_size); } return 1; } @@ -3771,23 +3777,26 @@ int FAST_FUNC bb_init_module_24(const char *m_filename, const char *options) struct utsname uts; int exit_status = EXIT_FAILURE; int m_has_modinfo; - char *m_name, *p; + char *m_name; #if ENABLE_FEATURE_INSMOD_VERSION_CHECKING char m_strversion[STRVERSIONLEN]; int m_version, m_crcs; #endif - int fd; + char *image; + size_t image_size = 64 * 1024 * 1024; uname(&uts); - fd = open_or_warn(m_filename, O_RDONLY); - if (fd < 0) + + /* Load module into memory and unzip if compressed */ + image = xmalloc_open_zipped_read_close(m_filename, &image_size); + if (!image) return EXIT_FAILURE; m_name = xstrdup(bb_basename(m_filename)); - p = strrchr(m_name, '.'); - if (p) *p = '\0'; + /* "module.o[.gz]" -> "module" */ + *strchrnul(m_name, '.') = '\0'; - f = obj_load(fd, LOADBITS); + f = obj_load(image, image_size, LOADBITS); m_has_modinfo = (get_modinfo_value(f, "kernel_version") != NULL); @@ -3816,7 +3825,7 @@ int FAST_FUNC bb_init_module_24(const char *m_filename, const char *options) #endif if (query_module(NULL, 0, NULL, 0, NULL)) - bb_error_msg_and_die("not configured to support old kernels"); + bb_error_msg_and_die("old (unsupported) kernel"); new_get_kernel_symbols(); k_crcs = new_is_kernel_checksummed(); @@ -3869,7 +3878,7 @@ int FAST_FUNC bb_init_module_24(const char *m_filename, const char *options) * the PROGBITS section was not loaded by the obj_load * now we can load them directly into the kernel memory */ - if (!obj_load_progbits(fd, f, (char*)m_addr)) { + if (!obj_load_progbits(image, image_size, f, (char*)m_addr)) { delete_module(m_name, 0); goto out; } @@ -3891,7 +3900,7 @@ int FAST_FUNC bb_init_module_24(const char *m_filename, const char *options) exit_status = EXIT_SUCCESS; out: - close(fd); + free(image); free(m_name); return exit_status;