1 files changed, 63 insertions, 21 deletions

diff --git a/kernel/module.c b/kernel/module.c
index aa183c9ac0a2..1c5cff34d9f2 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -422,7 +422,7 @@ static bool each_symbol_in_section(const struct symsearch *arr,
 }
 
 /* Returns true as soon as fn returns true, otherwise false. */
-bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
+static bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
 				    struct module *owner,
 				    void *data),
 			 void *data)
@@ -484,7 +484,6 @@ bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
 	}
 	return false;
 }
-EXPORT_SYMBOL_GPL(each_symbol_section);
 
 struct find_symbol_arg {
 	/* Input */
@@ -496,6 +495,7 @@ struct find_symbol_arg {
 	struct module *owner;
 	const s32 *crc;
 	const struct kernel_symbol *sym;
+	enum mod_license license;
 };
 
 static bool check_exported_symbol(const struct symsearch *syms,
@@ -505,9 +505,9 @@ static bool check_exported_symbol(const struct symsearch *syms,
 	struct find_symbol_arg *fsa = data;
 
 	if (!fsa->gplok) {
-		if (syms->licence == GPL_ONLY)
+		if (syms->license == GPL_ONLY)
 			return false;
-		if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
+		if (syms->license == WILL_BE_GPL_ONLY && fsa->warn) {
 			pr_warn("Symbol %s is being used by a non-GPL module, "
 				"which will not be allowed in the future\n",
 				fsa->name);
@@ -529,6 +529,7 @@ static bool check_exported_symbol(const struct symsearch *syms,
 	fsa->owner = owner;
 	fsa->crc = symversion(syms->crcs, symnum);
 	fsa->sym = &syms->start[symnum];
+	fsa->license = syms->license;
 	return true;
 }
 
@@ -585,9 +586,10 @@ static bool find_exported_symbol_in_section(const struct symsearch *syms,
 
 /* Find an exported symbol and return it, along with, (optional) crc and
  * (optional) module which owns it.  Needs preempt disabled or module_mutex. */
-const struct kernel_symbol *find_symbol(const char *name,
+static const struct kernel_symbol *find_symbol(const char *name,
 					struct module **owner,
 					const s32 **crc,
+					enum mod_license *license,
 					bool gplok,
 					bool warn)
 {
@@ -602,13 +604,14 @@ const struct kernel_symbol *find_symbol(const char *name,
 			*owner = fsa.owner;
 		if (crc)
 			*crc = fsa.crc;
+		if (license)
+			*license = fsa.license;
 		return fsa.sym;
 	}
 
 	pr_debug("Failed to find symbol %s\n", name);
 	return NULL;
 }
-EXPORT_SYMBOL_GPL(find_symbol);
 
 /*
  * Search for module by name: must hold module_mutex (or preempt disabled
@@ -869,7 +872,7 @@ static int add_module_usage(struct module *a, struct module *b)
 }
 
 /* Module a uses b: caller needs module_mutex() */
-int ref_module(struct module *a, struct module *b)
+static int ref_module(struct module *a, struct module *b)
 {
 	int err;
 
@@ -888,7 +891,6 @@ int ref_module(struct module *a, struct module *b)
 	}
 	return 0;
 }
-EXPORT_SYMBOL_GPL(ref_module);
 
 /* Clear the unload stuff of the module. */
 static void module_unload_free(struct module *mod)
@@ -1077,7 +1079,7 @@ void __symbol_put(const char *symbol)
 	struct module *owner;
 
 	preempt_disable();
-	if (!find_symbol(symbol, &owner, NULL, true, false))
+	if (!find_symbol(symbol, &owner, NULL, NULL, true, false))
 		BUG();
 	module_put(owner);
 	preempt_enable();
@@ -1169,11 +1171,10 @@ static inline void module_unload_free(struct module *mod)
 {
 }
 
-int ref_module(struct module *a, struct module *b)
+static int ref_module(struct module *a, struct module *b)
 {
 	return strong_try_module_get(b);
 }
-EXPORT_SYMBOL_GPL(ref_module);
 
 static inline int module_unload_init(struct module *mod)
 {
@@ -1356,7 +1357,7 @@ static inline int check_modstruct_version(const struct load_info *info,
 	 * locking is necessary -- use preempt_disable() to placate lockdep.
 	 */
 	preempt_disable();
-	if (!find_symbol("module_layout", NULL, &crc, true, false)) {
+	if (!find_symbol("module_layout", NULL, &crc, NULL, true, false)) {
 		preempt_enable();
 		BUG();
 	}
@@ -1430,6 +1431,24 @@ static int verify_namespace_is_imported(const struct load_info *info,
 	return 0;
 }
 
+static bool inherit_taint(struct module *mod, struct module *owner)
+{
+	if (!owner || !test_bit(TAINT_PROPRIETARY_MODULE, &owner->taints))
+		return true;
+
+	if (mod->using_gplonly_symbols) {
+		pr_err("%s: module using GPL-only symbols uses symbols from proprietary module %s.\n",
+			mod->name, owner->name);
+		return false;
+	}
+
+	if (!test_bit(TAINT_PROPRIETARY_MODULE, &mod->taints)) {
+		pr_warn("%s: module uses symbols from proprietary module %s, inheriting taint.\n",
+			mod->name, owner->name);
+		set_bit(TAINT_PROPRIETARY_MODULE, &mod->taints);
+	}
+	return true;
+}
 
 /* Resolve a symbol for this module.  I.e. if we find one, record usage. */
 static const struct kernel_symbol *resolve_symbol(struct module *mod,
@@ -1440,6 +1459,7 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod,
 	struct module *owner;
 	const struct kernel_symbol *sym;
 	const s32 *crc;
+	enum mod_license license;
 	int err;
 
 	/*
@@ -1449,11 +1469,19 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod,
 	 */
 	sched_annotate_sleep();
 	mutex_lock(&module_mutex);
-	sym = find_symbol(name, &owner, &crc,
+	sym = find_symbol(name, &owner, &crc, &license,
 			  !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
 	if (!sym)
 		goto unlock;
 
+	if (license == GPL_ONLY)
+		mod->using_gplonly_symbols = true;
+
+	if (!inherit_taint(mod, owner)) {
+		sym = NULL;
+		goto getname;
+	}
+
 	if (!check_version(info, name, mod, crc)) {
 		sym = ERR_PTR(-EINVAL);
 		goto getname;
@@ -1520,18 +1548,34 @@ struct module_sect_attrs {
 	struct module_sect_attr attrs[];
 };
 
+#define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4))
 static ssize_t module_sect_read(struct file *file, struct kobject *kobj,
 				struct bin_attribute *battr,
 				char *buf, loff_t pos, size_t count)
 {
 	struct module_sect_attr *sattr =
 		container_of(battr, struct module_sect_attr, battr);
+	char bounce[MODULE_SECT_READ_SIZE + 1];
+	size_t wrote;
 
 	if (pos != 0)
 		return -EINVAL;
 
-	return sprintf(buf, "0x%px\n",
-		       kallsyms_show_value(file->f_cred) ? (void *)sattr->address : NULL);
+	/*
+	 * Since we're a binary read handler, we must account for the
+	 * trailing NUL byte that sprintf will write: if "buf" is
+	 * too small to hold the NUL, or the NUL is exactly the last
+	 * byte, the read will look like it got truncated by one byte.
+	 * Since there is no way to ask sprintf nicely to not write
+	 * the NUL, we have to use a bounce buffer.
+	 */
+	wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n",
+			 kallsyms_show_value(file->f_cred)
+				? (void *)sattr->address : NULL);
+	count = min(count, wrote);
+	memcpy(buf, bounce, count);
+
+	return count;
 }
 
 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
@@ -1580,7 +1624,7 @@ static void add_sect_attrs(struct module *mod, const struct load_info *info)
 			goto out;
 		sect_attrs->nsections++;
 		sattr->battr.read = module_sect_read;
-		sattr->battr.size = 3 /* "0x", "\n" */ + (BITS_PER_LONG / 4);
+		sattr->battr.size = MODULE_SECT_READ_SIZE;
 		sattr->battr.attr.mode = 0400;
 		*(gattr++) = &(sattr++)->battr;
 	}
@@ -2220,7 +2264,7 @@ void *__symbol_get(const char *symbol)
 	const struct kernel_symbol *sym;
 
 	preempt_disable();
-	sym = find_symbol(symbol, &owner, NULL, true, true);
+	sym = find_symbol(symbol, &owner, NULL, NULL, true, true);
 	if (sym && strong_try_module_get(owner))
 		sym = NULL;
 	preempt_enable();
@@ -2256,7 +2300,7 @@ static int verify_exported_symbols(struct module *mod)
 	for (i = 0; i < ARRAY_SIZE(arr); i++) {
 		for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
 			if (find_symbol(kernel_symbol_name(s), &owner, NULL,
-					true, false)) {
+					NULL, true, false)) {
 				pr_err("%s: exports duplicate symbol %s"
 				       " (owned by %s)\n",
 				       mod->name, kernel_symbol_name(s),
@@ -3237,7 +3281,7 @@ static int find_module_sections(struct module *mod, struct load_info *info)
 	if (section_addr(info, "__obsparm"))
 		pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
 
-	info->debug = section_objs(info, "__verbose",
+	info->debug = section_objs(info, "__dyndbg",
 				   sizeof(*info->debug), &info->num_debug);
 
 	return 0;
@@ -4473,7 +4517,6 @@ struct module *__module_address(unsigned long addr)
 	}
 	return mod;
 }
-EXPORT_SYMBOL_GPL(__module_address);
 
 /*
  * is_module_text_address - is this address inside module code?
@@ -4512,7 +4555,6 @@ struct module *__module_text_address(unsigned long addr)
 	}
 	return mod;
 }
-EXPORT_SYMBOL_GPL(__module_text_address);
 
 /* Don't grab lock, we're oopsing. */
 void print_modules(void)