diff options
| -rw-r--r-- | init/Kconfig | 9 | ||||
| -rw-r--r-- | kernel/module.c | 44 |
2 files changed, 38 insertions, 15 deletions
diff --git a/init/Kconfig b/init/Kconfig index 6a44defac3e..f0e62e5ce0d 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -825,6 +825,15 @@ menuconfig MODULES If unsure, say Y. +config MODULE_FORCE_LOAD + bool "Forced module loading" + depends on MODULES + default n + help + This option allows loading of modules even if that would set the + 'F' (forced) taint, due to lack of version info. Which is + usually a really bad idea. + config MODULE_UNLOAD bool "Module unloading" depends on MODULES diff --git a/kernel/module.c b/kernel/module.c index 8674a390a2e..8e4528c9909 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -890,6 +890,19 @@ static struct module_attribute *modinfo_attrs[] = { static const char vermagic[] = VERMAGIC_STRING; +static int try_to_force_load(struct module *mod, const char *symname) +{ +#ifdef CONFIG_MODULE_FORCE_LOAD + if (!(tainted & TAINT_FORCED_MODULE)) + printk("%s: no version for \"%s\" found: kernel tainted.\n", + mod->name, symname); + add_taint_module(mod, TAINT_FORCED_MODULE); + return 0; +#else + return -ENOEXEC; +#endif +} + #ifdef CONFIG_MODVERSIONS static int check_version(Elf_Shdr *sechdrs, unsigned int versindex, @@ -914,18 +927,18 @@ static int check_version(Elf_Shdr *sechdrs, if (versions[i].crc == *crc) return 1; - printk("%s: disagrees about version of symbol %s\n", - mod->name, symname); DEBUGP("Found checksum %lX vs module %lX\n", *crc, versions[i].crc); - return 0; + goto bad_version; } - /* Not in module's version table. OK, but that taints the kernel. */ - if (!(tainted & TAINT_FORCED_MODULE)) - printk("%s: no version for \"%s\" found: kernel tainted.\n", - mod->name, symname); - add_taint_module(mod, TAINT_FORCED_MODULE); - return 1; + + if (!try_to_force_load(mod, symname)) + return 1; + +bad_version: + printk("%s: disagrees about version of symbol %s\n", + mod->name, symname); + return 0; } static inline int check_modstruct_version(Elf_Shdr *sechdrs, @@ -1853,9 +1866,9 @@ static struct module *load_module(void __user *umod, modmagic = get_modinfo(sechdrs, infoindex, "vermagic"); /* This is allowed: modprobe --force will invalidate it. */ if (!modmagic) { - add_taint_module(mod, TAINT_FORCED_MODULE); - printk(KERN_WARNING "%s: no version magic, tainting kernel.\n", - mod->name); + err = try_to_force_load(mod, "magic"); + if (err) + goto free_hdr; } else if (!same_magic(modmagic, vermagic)) { printk(KERN_ERR "%s: version magic '%s' should be '%s'\n", mod->name, modmagic, vermagic); @@ -2006,9 +2019,10 @@ static struct module *load_module(void __user *umod, (mod->num_gpl_future_syms && !gplfuturecrcindex) || (mod->num_unused_syms && !unusedcrcindex) || (mod->num_unused_gpl_syms && !unusedgplcrcindex)) { - printk(KERN_WARNING "%s: No versions for exported symbols." - " Tainting kernel.\n", mod->name); - add_taint_module(mod, TAINT_FORCED_MODULE); + printk(KERN_WARNING "%s: No versions for exported symbols.\n", mod->name); + err = try_to_force_load(mod, "nocrc"); + if (err) + goto cleanup; } #endif markersindex = find_sec(hdr, sechdrs, secstrings, "__markers"); |