3 files changed, 209 insertions, 22 deletions

diff --git a/scripts/mod/mk_elfconfig.c b/scripts/mod/mk_elfconfig.c
index 3c92c83733f4..725d61c0fb43 100644
--- a/scripts/mod/mk_elfconfig.c
+++ b/scripts/mod/mk_elfconfig.c
@@ -28,7 +28,7 @@ main(int argc, char **argv)
                 printf("#define KERNEL_ELFCLASS ELFCLASS64\n");
                 break;
         default:
-                abort();
+                exit(1);
         }
         switch (ei[EI_DATA]) {
         case ELFDATA2LSB:
@@ -38,7 +38,7 @@ main(int argc, char **argv)
                 printf("#define KERNEL_ELFDATA ELFDATA2MSB\n");
                 break;
         default:
-                abort();
+                exit(1);
         }
 
         if (sizeof(unsigned long) == 4) {
@@ -53,7 +53,7 @@ main(int argc, char **argv)
         else if (memcmp(endian_test.c, "\x02\x01", 2) == 0)
                 printf("#define HOST_ELFDATA ELFDATA2LSB\n");
         else
-                abort();
+                exit(1);
 
         if ((strcmp(argv[1], "v850") == 0) || (strcmp(argv[1], "h8300") == 0))
                 printf("#define MODULE_SYMBOL_PREFIX \"_\"\n");
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;
 
diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
index 861d866fcd83..d398c61e55ef 100644
--- a/scripts/mod/modpost.h
+++ b/scripts/mod/modpost.h
@@ -100,6 +100,7 @@ buf_write(struct buffer *buf, const char *s, int len);
 struct module {
         struct module *next;
         const char *name;
+        int gpl_compatible;
         struct symbol *unres;
         int seen;
         int skip;
@@ -115,6 +116,11 @@ struct elf_info {
         Elf_Shdr     *sechdrs;
         Elf_Sym      *symtab_start;
         Elf_Sym      *symtab_stop;
+        Elf_Section  export_sec;
+        Elf_Section  export_unused_sec;
+        Elf_Section  export_gpl_sec;
+        Elf_Section  export_unused_gpl_sec;
+        Elf_Section  export_gpl_future_sec;
         const char   *strtab;
         char         *modinfo;
         unsigned int modinfo_len;