From e00498258c215b46bd24f12ab3a2ed1bcb4772fe Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Sun, 16 Sep 2007 11:15:46 +0200 Subject: [PATCH] kbuild: make modpost detect unterminated device id lists Cause modpost to fail if any device id lists are incorrectly terminated, after reporting the offender. Improved reporting by akpm Signed-off-by: Kees Cook Cc: Greg KH Cc: Alexey Dobriyan Cc: Jeff Garzik Cc: Ben Collins Cc: Michael Wu Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Sam Ravnborg --- scripts/mod/file2alias.c | 40 +++++++++++++++++++++++++++++++++------- 1 file changed, 33 insertions(+), 7 deletions(-) diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c index 36e3754db5..7abee0f2d2 100644 --- a/scripts/mod/file2alias.c +++ b/scripts/mod/file2alias.c @@ -55,10 +55,14 @@ do { \ * Check that sizeof(device_id type) are consistent with size of section * in .o file. If in-consistent then userspace and kernel does not agree * on actual size which is a bug. + * Also verify that the final entry in the table is all zeros. **/ -static void device_id_size_check(const char *modname, const char *device_id, - unsigned long size, unsigned long id_size) +static void device_id_check(const char *modname, const char *device_id, + unsigned long size, unsigned long id_size, + void *symval) { + int i; + if (size % id_size || size < id_size) { fatal("%s: sizeof(struct %s_device_id)=%lu is not a modulo " "of the size of section __mod_%s_device_table=%lu.\n" @@ -66,6 +70,20 @@ static void device_id_size_check(const char *modname, const char *device_id, "in mod_devicetable.h\n", modname, device_id, id_size, device_id, size, device_id); } + /* Verify last one is a terminator */ + for (i = 0; i < id_size; i++ ) { + if (*(uint8_t*)(symval+size-id_size+i)) { + fprintf(stderr,"%s: struct %s_device_id is %lu bytes. " + "The last of %lu is:\n", + modname, device_id, id_size, size / id_size); + for (i = 0; i < id_size; i++ ) + fprintf(stderr,"0x%02x ", + *(uint8_t*)(symval+size-id_size+i) ); + fprintf(stderr,"\n"); + fatal("%s: struct %s_device_id is not terminated " + "with a NULL entry!\n", modname, device_id); + } + } } /* USB is special because the bcdDevice can be matched against a numeric range */ @@ -168,7 +186,7 @@ static void do_usb_table(void *symval, unsigned long size, unsigned int i; const unsigned long id_size = sizeof(struct usb_device_id); - device_id_size_check(mod->name, "usb", size, id_size); + device_id_check(mod->name, "usb", size, id_size, symval); /* Leave last one: it's the terminator. */ size -= id_size; @@ -535,7 +553,7 @@ static void do_table(void *symval, unsigned long size, char alias[500]; int (*do_entry)(const char *, void *entry, char *alias) = function; - device_id_size_check(mod->name, device_id, size, id_size); + device_id_check(mod->name, device_id, size, id_size, symval); /* Leave last one: it's the terminator. */ size -= id_size; @@ -557,14 +575,21 @@ void handle_moddevtable(struct module *mod, struct elf_info *info, Elf_Sym *sym, const char *symname) { void *symval; + char *zeros = NULL; /* We're looking for a section relative symbol */ if (!sym->st_shndx || sym->st_shndx >= info->hdr->e_shnum) return; - symval = (void *)info->hdr - + info->sechdrs[sym->st_shndx].sh_offset - + sym->st_value; + /* Handle all-NULL symbols allocated into .bss */ + if (info->sechdrs[sym->st_shndx].sh_type & SHT_NOBITS) { + zeros = calloc(1, sym->st_size); + symval = zeros; + } else { + symval = (void *)info->hdr + + info->sechdrs[sym->st_shndx].sh_offset + + sym->st_value; + } if (sym_is(symname, "__mod_pci_device_table")) do_table(symval, sym->st_size, @@ -637,6 +662,7 @@ void handle_moddevtable(struct module *mod, struct elf_info *info, do_table(symval, sym->st_size, sizeof(struct ssb_device_id), "ssb", do_ssb_entry, mod); + free(zeros); } /* Now add out buffered information to the generated C source */ -- 2.39.5