This is a note to let you know that I've just added the patch titled
modules: inherit TAINT_PROPRIETARY_MODULE
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
modules-inherit-taint_proprietary_module.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 262e6ae7081df304fc625cf368d5c2cbba2bb991 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@xxxxxx>
Date: Tue, 28 Jul 2020 23:33:33 +0200
Subject: modules: inherit TAINT_PROPRIETARY_MODULE
From: Christoph Hellwig <hch@xxxxxx>
commit 262e6ae7081df304fc625cf368d5c2cbba2bb991 upstream.
If a TAINT_PROPRIETARY_MODULE exports symbol, inherit the taint flag
for all modules importing these symbols, and don't allow loading
symbols from TAINT_PROPRIETARY_MODULE modules if the module previously
imported gplonly symbols. Add a anti-circumvention devices so people
don't accidentally get themselves into trouble this way.
Comment from Greg:
"Ah, the proven-to-be-illegal "GPL Condom" defense :)"
[jeyu: pr_info -> pr_err and pr_warn as per discussion]
Link: http://lore.kernel.org/r/20200730162957.GA22469@xxxxxx
Acked-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Jessica Yu <jeyu@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
include/linux/module.h | 1 +
kernel/module.c | 26 ++++++++++++++++++++++++++
2 files changed, 27 insertions(+)
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -376,6 +376,7 @@ struct module {
unsigned int num_gpl_syms;
const struct kernel_symbol *gpl_syms;
const s32 *gpl_crcs;
+ bool using_gplonly_symbols;
#ifdef CONFIG_UNUSED_SYMBOLS
/* unused exported symbols. */
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1429,6 +1429,24 @@ static int verify_namespace_is_imported(
return 0;
}
+static bool inherit_taint(struct module *mod, struct module *owner)
+{
+ 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);
+ 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);
+ set_bit(TAINT_PROPRIETARY_MODULE, &mod->taints);
+ }
+ return true;
+}
/* Resolve a symbol for this module. I.e. if we find one, record usage. */
static const struct kernel_symbol *resolve_symbol(struct module *mod,
@@ -1454,6 +1472,14 @@ static const struct kernel_symbol *resol
if (!sym)
goto unlock;
+ if (license == GPL_ONLY)
+ mod->using_gplonly_symbols = true;
+
+ if (!inherit_taint(mod, owner)) {
+ sym = NULL;
+ goto getname;
+ }
+
if (!check_version(info, name, mod, crc)) {
sym = ERR_PTR(-EINVAL);
goto getname;
Patches currently in stable-queue which might be from hch@xxxxxx are
queue-5.4/modules-unexport-__module_address.patch
queue-5.4/modules-mark-find_symbol-static.patch
queue-5.4/modules-return-licensing-information-from-find_symbol.patch
queue-5.4/modules-inherit-taint_proprietary_module.patch
queue-5.4/modules-mark-ref_module-static.patch
queue-5.4/modules-rename-the-licence-field-in-struct-symsearch-to-license.patch
queue-5.4/modules-unexport-__module_text_address.patch
queue-5.4/modules-mark-each_symbol_section-static.patch
