1 files changed, 200 insertions, 19 deletions

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index d0f86ed43f7a..dfde0e87a765 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -13,6 +13,7 @@
 
 #include <ctype.h>
 #include "modpost.h"
+#include "../../include/linux/license.h"
 
 /* Are we using CONFIG_MODVERSIONS? */
 int modversions = 0;
@@ -22,6 +23,11 @@ int have_vmlinux = 0;
 static int all_versions = 0;
 /* If we are modposting external module set to 1 */
 static int external_module = 0;
+/* How a symbol is exported */
+enum export {
+	export_plain,      export_unused,     export_gpl,
+	export_unused_gpl, export_gpl_future, export_unknown
+};
 
 void fatal(const char *fmt, ...)
 {
@@ -97,6 +103,7 @@ static struct module *new_module(char *modname)
 
 	/* add to list */
 	mod->name = p;
+	mod->gpl_compatible = -1;
 	mod->next = modules;
 	modules = mod;
 
@@ -118,6 +125,7 @@ struct symbol {
 	unsigned int kernel:1;     /* 1 if symbol is from kernel
 				    *  (only for external modules) **/
 	unsigned int preloaded:1;  /* 1 if symbol from Module.symvers */
+	enum export  export;       /* Type of export */
 	char name[0];
 };
 
@@ -153,7 +161,8 @@ static struct symbol *alloc_symbol(const char *name, unsigned int weak,
 }
 
 /* For the hash of exported symbols */
-static struct symbol *new_symbol(const char *name, struct module *module)
+static struct symbol *new_symbol(const char *name, struct module *module,
+				 enum export export)
 {
 	unsigned int hash;
 	struct symbol *new;
@@ -161,6 +170,7 @@ static struct symbol *new_symbol(const char *name, struct module *module)
 	hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
 	new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
 	new->module = module;
+	new->export = export;
 	return new;
 }
 
@@ -179,16 +189,63 @@ static struct symbol *find_symbol(const char *name)
 	return NULL;
 }
 
+static struct {
+	const char *str;
+	enum export export;
+} export_list[] = {
+	{ .str = "EXPORT_SYMBOL",            .export = export_plain },
+	{ .str = "EXPORT_UNUSED_SYMBOL",     .export = export_unused },
+	{ .str = "EXPORT_SYMBOL_GPL",        .export = export_gpl },
+	{ .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
+	{ .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
+	{ .str = "(unknown)",                .export = export_unknown },
+};
+
+
+static const char *export_str(enum export ex)
+{
+	return export_list[ex].str;
+}
+
+static enum export export_no(const char * s)
+{
+	int i;
+	if (!s)
+		return export_unknown;
+	for (i = 0; export_list[i].export != export_unknown; i++) {
+		if (strcmp(export_list[i].str, s) == 0)
+			return export_list[i].export;
+	}
+	return export_unknown;
+}
+
+static enum export export_from_sec(struct elf_info *elf, Elf_Section sec)
+{
+	if (sec == elf->export_sec)
+		return export_plain;
+	else if (sec == elf->export_unused_sec)
+		return export_unused;
+	else if (sec == elf->export_gpl_sec)
+		return export_gpl;
+	else if (sec == elf->export_unused_gpl_sec)
+		return export_unused_gpl;
+	else if (sec == elf->export_gpl_future_sec)
+		return export_gpl_future;
+	else
+		return export_unknown;
+}
+
 /**
  * Add an exported symbol - it may have already been added without a
  * CRC, in this case just update the CRC
  **/
-static struct symbol *sym_add_exported(const char *name, struct module *mod)
+static struct symbol *sym_add_exported(const char *name, struct module *mod,
+				       enum export export)
 {
 	struct symbol *s = find_symbol(name);
 
 	if (!s) {
-		s = new_symbol(name, mod);
+		s = new_symbol(name, mod, export);
 	} else {
 		if (!s->preloaded) {
 			warn("%s: '%s' exported twice. Previous export "
@@ -200,16 +257,17 @@ static struct symbol *sym_add_exported(const char *name, struct module *mod)
 	s->preloaded = 0;
 	s->vmlinux   = is_vmlinux(mod->name);
 	s->kernel    = 0;
+	s->export    = export;
 	return s;
 }
 
 static void sym_update_crc(const char *name, struct module *mod,
-			   unsigned int crc)
+			   unsigned int crc, enum export export)
 {
 	struct symbol *s = find_symbol(name);
 
 	if (!s)
-		s = new_symbol(name, mod);
+		s = new_symbol(name, mod, export);
 	s->crc = crc;
 	s->crc_valid = 1;
 }
@@ -283,7 +341,7 @@ static void parse_elf(struct elf_info *info, const char *filename)
 	hdr = grab_file(filename, &info->size);
 	if (!hdr) {
 		perror(filename);
-		abort();
+		exit(1);
 	}
 	info->hdr = hdr;
 	if (info->size < sizeof(*hdr))
@@ -309,13 +367,25 @@ static void parse_elf(struct elf_info *info, const char *filename)
 	for (i = 1; i < hdr->e_shnum; i++) {
 		const char *secstrings
 			= (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+		const char *secname;
 
 		if (sechdrs[i].sh_offset > info->size)
 			goto truncated;
-		if (strcmp(secstrings+sechdrs[i].sh_name, ".modinfo") == 0) {
+		secname = secstrings + sechdrs[i].sh_name;
+		if (strcmp(secname, ".modinfo") == 0) {
 			info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
 			info->modinfo_len = sechdrs[i].sh_size;
-		}
+		} else if (strcmp(secname, "__ksymtab") == 0)
+			info->export_sec = i;
+		else if (strcmp(secname, "__ksymtab_unused") == 0)
+			info->export_unused_sec = i;
+		else if (strcmp(secname, "__ksymtab_gpl") == 0)
+			info->export_gpl_sec = i;
+		else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
+			info->export_unused_gpl_sec = i;
+		else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
+			info->export_gpl_future_sec = i;
+
 		if (sechdrs[i].sh_type != SHT_SYMTAB)
 			continue;
 
@@ -353,6 +423,7 @@ static void handle_modversions(struct module *mod, struct elf_info *info,
 			       Elf_Sym *sym, const char *symname)
 {
 	unsigned int crc;
+	enum export export = export_from_sec(info, sym->st_shndx);
 
 	switch (sym->st_shndx) {
 	case SHN_COMMON:
@@ -362,7 +433,8 @@ static void handle_modversions(struct module *mod, struct elf_info *info,
 		/* CRC'd symbol */
 		if (memcmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
 			crc = (unsigned int) sym->st_value;
-			sym_update_crc(symname + strlen(CRC_PFX), mod, crc);
+			sym_update_crc(symname + strlen(CRC_PFX), mod, crc,
+					export);
 		}
 		break;
 	case SHN_UNDEF:
@@ -406,7 +478,8 @@ static void handle_modversions(struct module *mod, struct elf_info *info,
 	default:
 		/* All exported symbols */
 		if (memcmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
-			sym_add_exported(symname + strlen(KSYMTAB_PFX), mod);
+			sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
+					export);
 		}
 		if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
 			mod->has_init = 1;
@@ -437,13 +510,18 @@ static char *next_string(char *string, unsigned long *secsize)
 	return string;
 }
 
-static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
-			 const char *tag)
+static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len,
+			      const char *tag, char *info)
 {
 	char *p;
 	unsigned int taglen = strlen(tag);
 	unsigned long size = modinfo_len;
 
+	if (info) {
+		size -= info - (char *)modinfo;
+		modinfo = next_string(info, &size);
+	}
+
 	for (p = modinfo; p; p = next_string(p, &size)) {
 		if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
 			return p + taglen + 1;
@@ -451,6 +529,13 @@ static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
 	return NULL;
 }
 
+static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
+			 const char *tag)
+
+{
+	return get_next_modinfo(modinfo, modinfo_len, tag, NULL);
+}
+
 /**
  * Test if string s ends in string sub
  * return 0 if match
@@ -821,6 +906,10 @@ static int init_section_ref_ok(const char *name)
 		".pci_fixup_final",
 		".pdr",
 		"__param",
+		"__ex_table",
+		".fixup",
+		".smp_locks",
+		".plt",  /* seen on ARCH=um build on x86_64. Harmless */
 		NULL
 	};
 	/* Start of section names */
@@ -846,6 +935,8 @@ static int init_section_ref_ok(const char *name)
 	for (s = namelist3; *s; s++)
 		if (strstr(name, *s) != NULL)
 			return 1;
+	if (strrcmp(name, ".init") == 0)
+		return 1;
 	return 0;
 }
 
@@ -892,6 +983,10 @@ static int exit_section_ref_ok(const char *name)
 		".exitcall.exit",
 		".eh_frame",
 		".stab",
+		"__ex_table",
+		".fixup",
+		".smp_locks",
+		".plt",  /* seen on ARCH=um build on x86_64. Harmless */
 		NULL
 	};
 	/* Start of section names */
@@ -921,6 +1016,7 @@ static void read_symbols(char *modname)
 {
 	const char *symname;
 	char *version;
+	char *license;
 	struct module *mod;
 	struct elf_info info = { };
 	Elf_Sym *sym;
@@ -936,6 +1032,18 @@ static void read_symbols(char *modname)
 		mod->skip = 1;
 	}
 
+	license = get_modinfo(info.modinfo, info.modinfo_len, "license");
+	while (license) {
+		if (license_is_gpl_compatible(license))
+			mod->gpl_compatible = 1;
+		else {
+			mod->gpl_compatible = 0;
+			break;
+		}
+		license = get_next_modinfo(info.modinfo, info.modinfo_len,
+					   "license", license);
+	}
+
 	for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
 		symname = info.strtab + sym->st_name;
 
@@ -992,6 +1100,67 @@ void buf_write(struct buffer *buf, const char *s, int len)
 	buf->pos += len;
 }
 
+static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
+{
+	const char *e = is_vmlinux(m) ?"":".ko";
+
+	switch (exp) {
+	case export_gpl:
+		fatal("modpost: GPL-incompatible module %s%s "
+		      "uses GPL-only symbol '%s'\n", m, e, s);
+		break;
+	case export_unused_gpl:
+		fatal("modpost: GPL-incompatible module %s%s "
+		      "uses GPL-only symbol marked UNUSED '%s'\n", m, e, s);
+		break;
+	case export_gpl_future:
+		warn("modpost: GPL-incompatible module %s%s "
+		      "uses future GPL-only symbol '%s'\n", m, e, s);
+		break;
+	case export_plain:
+	case export_unused:
+	case export_unknown:
+		/* ignore */
+		break;
+	}
+}
+
+static void check_for_unused(enum export exp, const char* m, const char* s)
+{
+	const char *e = is_vmlinux(m) ?"":".ko";
+
+	switch (exp) {
+	case export_unused:
+	case export_unused_gpl:
+		warn("modpost: module %s%s "
+		      "uses symbol '%s' marked UNUSED\n", m, e, s);
+		break;
+	default:
+		/* ignore */
+		break;
+	}
+}
+
+static void check_exports(struct module *mod)
+{
+	struct symbol *s, *exp;
+
+	for (s = mod->unres; s; s = s->next) {
+		const char *basename;
+		exp = find_symbol(s->name);
+		if (!exp || exp->module == mod)
+			continue;
+		basename = strrchr(mod->name, '/');
+		if (basename)
+			basename++;
+		else
+			basename = mod->name;
+		if (!mod->gpl_compatible)
+			check_for_gpl_usage(exp->export, basename, exp->name);
+		check_for_unused(exp->export, basename, exp->name);
+        }
+}
+
 /**
  * Header for the generated file
  **/
@@ -1142,6 +1311,9 @@ static void write_if_changed(struct buffer *b, const char *fname)
 	fclose(file);
 }
 
+/* parse Module.symvers file. line format:
+ * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
+ **/
 static void read_dump(const char *fname, unsigned int kernel)
 {
 	unsigned long size, pos = 0;
@@ -1153,7 +1325,7 @@ static void read_dump(const char *fname, unsigned int kernel)
 		return;
 
 	while ((line = get_next_line(&pos, file, size))) {
-		char *symname, *modname, *d;
+		char *symname, *modname, *d, *export, *end;
 		unsigned int crc;
 		struct module *mod;
 		struct symbol *s;
@@ -1164,8 +1336,10 @@ static void read_dump(const char *fname, unsigned int kernel)
 		if (!(modname = strchr(symname, '\t')))
 			goto fail;
 		*modname++ = '\0';
-		if (strchr(modname, '\t'))
-			goto fail;
+		if ((export = strchr(modname, '\t')) != NULL)
+			*export++ = '\0';
+		if (export && ((end = strchr(export, '\t')) != NULL))
+			*end = '\0';
 		crc = strtoul(line, &d, 16);
 		if (*symname == '\0' || *modname == '\0' || *d != '\0')
 			goto fail;
@@ -1177,10 +1351,10 @@ static void read_dump(const char *fname, unsigned int kernel)
 			mod = new_module(NOFAIL(strdup(modname)));
 			mod->skip = 1;
 		}
-		s = sym_add_exported(symname, mod);
+		s = sym_add_exported(symname, mod, export_no(export));
 		s->kernel    = kernel;
 		s->preloaded = 1;
-		sym_update_crc(symname, mod, crc);
+		sym_update_crc(symname, mod, crc, export_no(export));
 	}
 	return;
 fail:
@@ -1210,9 +1384,10 @@ static void write_dump(const char *fname)
 		symbol = symbolhash[n];
 		while (symbol) {
 			if (dump_sym(symbol))
-				buf_printf(&buf, "0x%08x\t%s\t%s\n",
+				buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",
 					symbol->crc, symbol->name,
-					symbol->module->name);
+					symbol->module->name,
+					export_str(symbol->export));
 			symbol = symbol->next;
 		}
 	}
@@ -1263,6 +1438,12 @@ int main(int argc, char **argv)
 	for (mod = modules; mod; mod = mod->next) {
 		if (mod->skip)
 			continue;
+		check_exports(mod);
+	}
+
+	for (mod = modules; mod; mod = mod->next) {
+		if (mod->skip)
+			continue;
 
 		buf.pos = 0;