diff options
Diffstat (limited to 'kernel/module.c')
| -rw-r--r-- | kernel/module.c | 149 |
1 files changed, 122 insertions, 27 deletions
diff --git a/kernel/module.c b/kernel/module.c index 4edbd9c11aca..6085f5ef88ea 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -58,6 +58,8 @@ #include <linux/jump_label.h> #include <linux/pfn.h> #include <linux/bsearch.h> +#include <linux/fips.h> +#include "module-internal.h" #define CREATE_TRACE_POINTS #include <trace/events/module.h> @@ -102,6 +104,43 @@ static LIST_HEAD(modules); struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */ #endif /* CONFIG_KGDB_KDB */ +#ifdef CONFIG_MODULE_SIG +#ifdef CONFIG_MODULE_SIG_FORCE +static bool sig_enforce = true; +#else +static bool sig_enforce = false; + +static int param_set_bool_enable_only(const char *val, + const struct kernel_param *kp) +{ + int err; + bool test; + struct kernel_param dummy_kp = *kp; + + dummy_kp.arg = &test; + + err = param_set_bool(val, &dummy_kp); + if (err) + return err; + + /* Don't let them unset it once it's set! */ + if (!test && sig_enforce) + return -EROFS; + + if (test) + sig_enforce = true; + return 0; +} + +static const struct kernel_param_ops param_ops_bool_enable_only = { + .set = param_set_bool_enable_only, + .get = param_get_bool, +}; +#define param_check_bool_enable_only param_check_bool + +module_param(sig_enforce, bool_enable_only, 0644); +#endif /* !CONFIG_MODULE_SIG_FORCE */ +#endif /* CONFIG_MODULE_SIG */ /* Block module loading/unloading? */ int modules_disabled = 0; @@ -136,6 +175,7 @@ struct load_info { unsigned long symoffs, stroffs; struct _ddebug *debug; unsigned int num_debug; + bool sig_ok; struct { unsigned int sym, str, mod, vers, info, pcpu; } index; @@ -1949,26 +1989,6 @@ static int simplify_symbols(struct module *mod, const struct load_info *info) return ret; } -int __weak apply_relocate(Elf_Shdr *sechdrs, - const char *strtab, - unsigned int symindex, - unsigned int relsec, - struct module *me) -{ - pr_err("module %s: REL relocation unsupported\n", me->name); - return -ENOEXEC; -} - -int __weak apply_relocate_add(Elf_Shdr *sechdrs, - const char *strtab, - unsigned int symindex, - unsigned int relsec, - struct module *me) -{ - pr_err("module %s: RELA relocation unsupported\n", me->name); - return -ENOEXEC; -} - static int apply_relocations(struct module *mod, const struct load_info *info) { unsigned int i; @@ -2399,7 +2419,44 @@ static inline void kmemleak_load_module(const struct module *mod, } #endif -/* Sets info->hdr and info->len. */ +#ifdef CONFIG_MODULE_SIG +static int module_sig_check(struct load_info *info, + const void *mod, unsigned long *_len) +{ + int err = -ENOKEY; + unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1; + unsigned long len = *_len; + + if (len > markerlen && + memcmp(mod + len - markerlen, MODULE_SIG_STRING, markerlen) == 0) { + /* We truncate the module to discard the signature */ + *_len -= markerlen; + err = mod_verify_sig(mod, _len); + } + + if (!err) { + info->sig_ok = true; + return 0; + } + + /* Not having a signature is only an error if we're strict. */ + if (err < 0 && fips_enabled) + panic("Module verification failed with error %d in FIPS mode\n", + err); + if (err == -ENOKEY && !sig_enforce) + err = 0; + + return err; +} +#else /* !CONFIG_MODULE_SIG */ +static int module_sig_check(struct load_info *info, + void *mod, unsigned long *len) +{ + return 0; +} +#endif /* !CONFIG_MODULE_SIG */ + +/* Sets info->hdr, info->len and info->sig_ok. */ static int copy_and_check(struct load_info *info, const void __user *umod, unsigned long len, const char __user *uargs) @@ -2419,6 +2476,10 @@ static int copy_and_check(struct load_info *info, goto free_hdr; } + err = module_sig_check(info, hdr, &len); + if (err) + goto free_hdr; + /* Sanity checks against insmoding binaries or wrong arch, weird elf version */ if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0 @@ -2730,6 +2791,10 @@ static int check_module_license_and_versions(struct module *mod) if (strcmp(mod->name, "driverloader") == 0) add_taint_module(mod, TAINT_PROPRIETARY_MODULE); + /* lve claims to be GPL but upstream won't provide source */ + if (strcmp(mod->name, "lve") == 0) + add_taint_module(mod, TAINT_PROPRIETARY_MODULE); + #ifdef CONFIG_MODVERSIONS if ((mod->num_syms && !mod->crcs) || (mod->num_gpl_syms && !mod->gpl_crcs) @@ -2861,6 +2926,20 @@ static int post_relocation(struct module *mod, const struct load_info *info) return module_finalize(info->hdr, info->sechdrs, mod); } +/* Is this module of this name done loading? No locks held. */ +static bool finished_loading(const char *name) +{ + struct module *mod; + bool ret; + + mutex_lock(&module_mutex); + mod = find_module(name); + ret = !mod || mod->state != MODULE_STATE_COMING; + mutex_unlock(&module_mutex); + + return ret; +} + /* Allocate and load the module: note that size of section 0 is always zero, and we rely on this for optional sections. */ static struct module *load_module(void __user *umod, @@ -2868,7 +2947,7 @@ static struct module *load_module(void __user *umod, const char __user *uargs) { struct load_info info = { NULL, }; - struct module *mod; + struct module *mod, *old; long err; pr_debug("load_module: umod=%p, len=%lu, uargs=%p\n", @@ -2886,6 +2965,12 @@ static struct module *load_module(void __user *umod, goto free_copy; } +#ifdef CONFIG_MODULE_SIG + mod->sig_ok = info.sig_ok; + if (!mod->sig_ok) + add_taint_module(mod, TAINT_FORCED_MODULE); +#endif + /* Now module is in final location, initialize linked lists, etc. */ err = module_unload_init(mod); if (err) @@ -2934,8 +3019,18 @@ static struct module *load_module(void __user *umod, * function to insert in a way safe to concurrent readers. * The mutex protects against concurrent writers. */ +again: mutex_lock(&module_mutex); - if (find_module(mod->name)) { + if ((old = find_module(mod->name)) != NULL) { + if (old->state == MODULE_STATE_COMING) { + /* Wait in case it fails to load. */ + mutex_unlock(&module_mutex); + err = wait_event_interruptible(module_wq, + finished_loading(mod->name)); + if (err) + goto free_arch_cleanup; + goto again; + } err = -EEXIST; goto unlock; } @@ -2975,7 +3070,7 @@ static struct module *load_module(void __user *umod, /* Unlink carefully: kallsyms could be walking list. */ list_del_rcu(&mod->list); module_bug_cleanup(mod); - + wake_up_all(&module_wq); ddebug: dynamic_debug_remove(info.debug); unlock: @@ -3050,7 +3145,7 @@ SYSCALL_DEFINE3(init_module, void __user *, umod, blocking_notifier_call_chain(&module_notify_list, MODULE_STATE_GOING, mod); free_module(mod); - wake_up(&module_wq); + wake_up_all(&module_wq); return ret; } if (ret > 0) { @@ -3062,9 +3157,8 @@ SYSCALL_DEFINE3(init_module, void __user *, umod, dump_stack(); } - /* Now it's a first class citizen! Wake up anyone waiting for it. */ + /* Now it's a first class citizen! */ mod->state = MODULE_STATE_LIVE; - wake_up(&module_wq); blocking_notifier_call_chain(&module_notify_list, MODULE_STATE_LIVE, mod); @@ -3087,6 +3181,7 @@ SYSCALL_DEFINE3(init_module, void __user *, umod, mod->init_ro_size = 0; mod->init_text_size = 0; mutex_unlock(&module_mutex); + wake_up_all(&module_wq); return 0; } |