[PATCH] module: show disallowed symbol name for inherit_taint()

From: Lecopzer Chen
Date: Tue Apr 26 2022 - 00:21:55 EST


The error log for inherit_taint() doesn't really help to find the symbols
which violate GPL rules.

For example,
if a module has 50 disallowed symbols, the log only shows the content below
and is duplicated with 50 lines.
AAA: module using GPL-only symbols uses symbols from proprietary module BBB.
AAA: module using GPL-only symbols uses symbols from proprietary module BBB.
...

This patch add symbol name to tell the offending symbols explicitly.

To-be:
AAA: module using GPL-only symbols uses symbols SS1 from proprietary module BBB.
AAA: module using GPL-only symbols uses symbols SS2 from proprietary module BBB.
...

Signed-off-by: Lecopzer Chen <lecopzer.chen@xxxxxxxxxxxx>
---
kernel/module.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/kernel/module.c b/kernel/module.c
index 6cea788fd965..30973f0d2b7c 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1372,20 +1372,20 @@ static int verify_namespace_is_imported(const struct load_info *info,
return 0;
}

-static bool inherit_taint(struct module *mod, struct module *owner)
+static bool inherit_taint(struct module *mod, struct module *owner, const char *name)
{
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);
+ pr_err("%s: module using GPL-only symbols uses symbols %s from proprietary module %s.\n",
+ mod->name, 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);
+ pr_warn("%s: module uses symbols %s from proprietary module %s, inheriting taint.\n",
+ mod->name, name, owner->name);
set_bit(TAINT_PROPRIETARY_MODULE, &mod->taints);
}
return true;
@@ -1417,7 +1417,7 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod,
if (fsa.license == GPL_ONLY)
mod->using_gplonly_symbols = true;

- if (!inherit_taint(mod, fsa.owner)) {
+ if (!inherit_taint(mod, fsa.owner, name)) {
fsa.sym = NULL;
goto getname;
}
--
2.18.0