kbuild: fix segv in modpost

Parsing an old Modules.symvers file casued modpost to SEGV.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 0dd16177642de15ba6593c83ed5d12553d425f2e..65411665e13c45697fccb76885eea9fd8bc9f721 100644 (file)
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -205,6 +205,8 @@ static const char *export_str(enum export ex)
 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;
@@ -1271,7 +1273,7 @@ static void write_if_changed(struct buffer *b, const char *fname)
 }
 
 /* parse Module.symvers file. line format:
- * 0x12345678<tab>symbol<tab>module[<tab>export]
+ * 0x12345678<tab>symbol<tab>module[[<tab>export]<tab>something]
  **/
 static void read_dump(const char *fname, unsigned int kernel)
 {
@@ -1284,7 +1286,7 @@ static void read_dump(const char *fname, unsigned int kernel)
                return;
 
        while ((line = get_next_line(&pos, file, size))) {
-               char *symname, *modname, *d, *export;
+               char *symname, *modname, *d, *export, *end;
                unsigned int crc;
                struct module *mod;
                struct symbol *s;
@@ -1297,7 +1299,8 @@ static void read_dump(const char *fname, unsigned int kernel)
                *modname++ = '\0';
                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;