diff options
Diffstat (limited to 'kernel/module.c')
| -rw-r--r-- | kernel/module.c | 114 |
1 files changed, 100 insertions, 14 deletions
diff --git a/kernel/module.c b/kernel/module.c index 9ee93421269c..ff2d7359a418 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -7,6 +7,7 @@ #include <linux/export.h> #include <linux/extable.h> #include <linux/moduleloader.h> +#include <linux/module_signature.h> #include <linux/trace_events.h> #include <linux/init.h> #include <linux/kallsyms.h> @@ -544,12 +545,20 @@ static const char *kernel_symbol_name(const struct kernel_symbol *sym) #endif } -static int cmp_name(const void *va, const void *vb) +static const char *kernel_symbol_namespace(const struct kernel_symbol *sym) { - const char *a; - const struct kernel_symbol *b; - a = va; b = vb; - return strcmp(a, kernel_symbol_name(b)); +#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS + if (!sym->namespace_offset) + return NULL; + return offset_to_ptr(&sym->namespace_offset); +#else + return sym->namespace; +#endif +} + +static int cmp_name(const void *name, const void *sym) +{ + return strcmp(name, kernel_symbol_name(sym)); } static bool find_exported_symbol_in_section(const struct symsearch *syms, @@ -1379,6 +1388,41 @@ static inline int same_magic(const char *amagic, const char *bmagic, } #endif /* CONFIG_MODVERSIONS */ +static char *get_modinfo(const struct load_info *info, const char *tag); +static char *get_next_modinfo(const struct load_info *info, const char *tag, + char *prev); + +static int verify_namespace_is_imported(const struct load_info *info, + const struct kernel_symbol *sym, + struct module *mod) +{ + const char *namespace; + char *imported_namespace; + + namespace = kernel_symbol_namespace(sym); + if (namespace) { + imported_namespace = get_modinfo(info, "import_ns"); + while (imported_namespace) { + if (strcmp(namespace, imported_namespace) == 0) + return 0; + imported_namespace = get_next_modinfo( + info, "import_ns", imported_namespace); + } +#ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS + pr_warn( +#else + pr_err( +#endif + "%s: module uses symbol (%s) from namespace %s, but does not import it.\n", + mod->name, kernel_symbol_name(sym), namespace); +#ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS + return -EINVAL; +#endif + } + return 0; +} + + /* Resolve a symbol for this module. I.e. if we find one, record usage. */ static const struct kernel_symbol *resolve_symbol(struct module *mod, const struct load_info *info, @@ -1407,6 +1451,12 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod, goto getname; } + err = verify_namespace_is_imported(info, sym, mod); + if (err) { + sym = ERR_PTR(err); + goto getname; + } + err = ref_module(mod, owner); if (err) { sym = ERR_PTR(err); @@ -2481,7 +2531,8 @@ static char *next_string(char *string, unsigned long *secsize) return string; } -static char *get_modinfo(struct load_info *info, const char *tag) +static char *get_next_modinfo(const struct load_info *info, const char *tag, + char *prev) { char *p; unsigned int taglen = strlen(tag); @@ -2492,13 +2543,25 @@ static char *get_modinfo(struct load_info *info, const char *tag) * get_modinfo() calls made before rewrite_section_headers() * must use sh_offset, as sh_addr isn't set! */ - for (p = (char *)info->hdr + infosec->sh_offset; p; p = next_string(p, &size)) { + char *modinfo = (char *)info->hdr + infosec->sh_offset; + + if (prev) { + size -= prev - modinfo; + modinfo = next_string(prev, &size); + } + + for (p = modinfo; p; p = next_string(p, &size)) { if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=') return p + taglen + 1; } return NULL; } +static char *get_modinfo(const struct load_info *info, const char *tag) +{ + return get_next_modinfo(info, tag, NULL); +} + static void setup_modinfo(struct module *mod, struct load_info *info) { struct module_attribute *attr; @@ -2776,8 +2839,9 @@ static inline void kmemleak_load_module(const struct module *mod, #ifdef CONFIG_MODULE_SIG static int module_sig_check(struct load_info *info, int flags) { - int err = -ENOKEY; + int err = -ENODATA; const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1; + const char *reason; const void *mod = info->hdr; /* @@ -2792,16 +2856,38 @@ static int module_sig_check(struct load_info *info, int flags) err = mod_verify_sig(mod, info); } - if (!err) { + switch (err) { + case 0: info->sig_ok = true; return 0; - } - /* Not having a signature is only an error if we're strict. */ - if (err == -ENOKEY && !is_module_sig_enforced()) - err = 0; + /* We don't permit modules to be loaded into trusted kernels + * without a valid signature on them, but if we're not + * enforcing, certain errors are non-fatal. + */ + case -ENODATA: + reason = "Loading of unsigned module"; + goto decide; + case -ENOPKG: + reason = "Loading of module with unsupported crypto"; + goto decide; + case -ENOKEY: + reason = "Loading of module with unavailable key"; + decide: + if (is_module_sig_enforced()) { + pr_notice("%s is rejected\n", reason); + return -EKEYREJECTED; + } - return err; + return security_locked_down(LOCKDOWN_MODULE_SIGNATURE); + + /* All other errors are fatal, including nomem, unparseable + * signatures and signature check failures - even if signatures + * aren't required. + */ + default: + return err; + } } #else /* !CONFIG_MODULE_SIG */ static int module_sig_check(struct load_info *info, int flags) |