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

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

[Lecopzer Chen]

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

For example,
if a module has 300 symbol and includes 50 disallowed symbols,
the log only shows the content below and we have no idea what symbol is.
    AAA: module using GPL-only symbols uses symbols from proprietary module BBB.

It's hard for user who doesn't really know how the symbol was parsing.

This patch add symbol name to tell the offending symbols explicitly.
    AAA: module using GPL-only symbols uses symbols SSS from proprietary module BBB.

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

diff --git a/kernel/module/main.c b/kernel/module/main.c
index 05a42d8fcd7a..a90084c44c55 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -1049,20 +1049,20 @@ 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;
@@ -1094,7 +1094,7 @@ 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

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

[Luis Chamberlain]

On Wed, Apr 27, 2022 at 03:36:06PM +0800, Lecopzer Chen wrote:
> The error log for inherit_taint() doesn't really help to find the
> symbol which violates GPL rules.
> 
> For example,
> if a module has 300 symbol and includes 50 disallowed symbols,
> the log only shows the content below and we have no idea what symbol is.
>     AAA: module using GPL-only symbols uses symbols from proprietary module BBB.
> 
> It's hard for user who doesn't really know how the symbol was parsing.
> 
> This patch add symbol name to tell the offending symbols explicitly.
>     AAA: module using GPL-only symbols uses symbols SSS from proprietary module BBB.
> 
> Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com>

Thanks, pushed onto modules-testing. If there are no issues I'll
eventually push this onto modules-next.

  Luis