Since commit 13b25489b6f8 ("kbuild: change working directory to external
module directory with M="), module paths are always relative to the top
of the external module tree.
The module paths recorded in Module.symvers is no longer globally unique
when they are passed via KBUILD_EXTRA_SYMBOLS for building other external
modules, which may result in false positive "exported twice" errors.
Such errors should not occur because external modules should be able to
override in-tree modules.
To address this, record the dump file path in struct module and check it
when searching for a module.
Fixes: 13b25489b6f8 ("kbuild: change working directory to external module directory with M=")
Reported-by: Jon Hunter <jonathanh@xxxxxxxxxx>
Closes: https://lore.kernel.org/all/eb21a546-a19c-40df-b821-bbba80f19a3d@xxxxxxxxxx/
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
---
scripts/mod/modpost.c | 17 +++++++++--------
scripts/mod/modpost.h | 3 ++-
2 files changed, 11 insertions(+), 9 deletions(-)
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index fb787a5715f5..94ee49207a45 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -155,12 +155,13 @@ char *get_line(char **stringp)
/* A list of all modules we processed */
LIST_HEAD(modules);
-static struct module *find_module(const char *modname)
+static struct module *find_module(const char *filename, const char *modname)
{
struct module *mod;
list_for_each_entry(mod, &modules, list) {
- if (strcmp(mod->name, modname) == 0)
+ if (!strcmp(mod->dump_file, filename) &&
+ !strcmp(mod->name, modname))
return mod;
}
return NULL;
@@ -2030,10 +2031,10 @@ static void read_dump(const char *fname)
continue;
}
- mod = find_module(modname);
+ mod = find_module(fname, modname);
if (!mod) {
mod = new_module(modname, strlen(modname));
- mod->from_dump = true;
+ mod->dump_file = fname;
}
s = sym_add_exported(symname, mod, gpl_only, namespace);
sym_set_crc(s, crc);
@@ -2052,7 +2053,7 @@ static void write_dump(const char *fname)
struct symbol *sym;
list_for_each_entry(mod, &modules, list) {
- if (mod->from_dump)
+ if (mod->dump_file)
continue;
list_for_each_entry(sym, &mod->exported_symbols, list) {
if (trim_unused_exports && !sym->used)
@@ -2076,7 +2077,7 @@ static void write_namespace_deps_files(const char *fname)
list_for_each_entry(mod, &modules, list) {
- if (mod->from_dump || list_empty(&mod->missing_namespaces))
+ if (mod->dump_file || list_empty(&mod->missing_namespaces))
continue;
buf_printf(&ns_deps_buf, "%s.ko:", mod->name);
@@ -2194,7 +2195,7 @@ int main(int argc, char **argv)
read_symbols_from_files(files_source);
list_for_each_entry(mod, &modules, list) {
- if (mod->from_dump || mod->is_vmlinux)
+ if (mod->dump_file || mod->is_vmlinux)
continue;
check_modname_len(mod);
@@ -2205,7 +2206,7 @@ int main(int argc, char **argv)
handle_white_list_exports(unused_exports_white_list);
list_for_each_entry(mod, &modules, list) {
- if (mod->from_dump)
+ if (mod->dump_file)
continue;
if (mod->is_vmlinux)
diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
index 49848fcbe2a1..8b72c227ebf4 100644
--- a/scripts/mod/modpost.h
+++ b/scripts/mod/modpost.h
@@ -95,14 +95,15 @@ struct module_alias {
/**
* struct module - represent a module (vmlinux or *.ko)
*
+ * @dump_file: path to the .symvers file if loaded from a file
* @aliases: list head for module_aliases
*/
struct module {
struct list_head list;
struct list_head exported_symbols;
struct list_head unresolved_symbols;
+ const char *dump_file;
bool is_gpl_compatible;
- bool from_dump; /* true if module was loaded from *.symvers */
bool is_vmlinux;
bool seen;
bool has_init;
