From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 69C3DC142 for ; Mon, 4 Sep 2023 18:36:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E0E11C433C8; Mon, 4 Sep 2023 18:36:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1693852610; bh=8ptofNUWLkErs0orxWI2bRH4Cndt2V+p2Sg5QVUh+Tw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rkCvTmRwenblOttXM/A+l9qnAxP0liRuhOb5iFACmb1EWFYNtziSKfP63z3BCHE6v h6C16bb03eOHkTP9tzBe36Ri4hBQM98lFzFts3D3+myM0E+eFnx7pz02ywuTwSC4kE 5UhVIHFOYQouGtbDL0PwVaQnARim9BfXLSpz/XlY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Christoph Hellwig , Luis Chamberlain Subject: [PATCH 5.15 08/28] modules: only allow symbol_get of EXPORT_SYMBOL_GPL modules Date: Mon, 4 Sep 2023 19:30:39 +0100 Message-ID: <20230904182945.570534362@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230904182945.178705038@linuxfoundation.org> References: <20230904182945.178705038@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Christoph Hellwig commit 9011e49d54dcc7653ebb8a1e05b5badb5ecfa9f9 upstream. It has recently come to my attention that nvidia is circumventing the protection added in 262e6ae7081d ("modules: inherit TAINT_PROPRIETARY_MODULE") by importing exports from their proprietary modules into an allegedly GPL licensed module and then rexporting them. Given that symbol_get was only ever intended for tightly cooperating modules using very internal symbols it is logical to restrict it to being used on EXPORT_SYMBOL_GPL and prevent nvidia from costly DMCA Circumvention of Access Controls law suites. All symbols except for four used through symbol_get were already exported as EXPORT_SYMBOL_GPL, and the remaining four ones were switched over in the preparation patches. Fixes: 262e6ae7081d ("modules: inherit TAINT_PROPRIETARY_MODULE") Signed-off-by: Christoph Hellwig Reviewed-by: Greg Kroah-Hartman Signed-off-by: Luis Chamberlain Signed-off-by: Greg Kroah-Hartman --- kernel/module.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) --- a/kernel/module.c +++ b/kernel/module.c @@ -2220,12 +2220,20 @@ void *__symbol_get(const char *symbol) }; preempt_disable(); - if (!find_symbol(&fsa) || strong_try_module_get(fsa.owner)) { - preempt_enable(); - return NULL; + if (!find_symbol(&fsa)) + goto fail; + if (fsa.license != GPL_ONLY) { + pr_warn("failing symbol_get of non-GPLONLY symbol %s.\n", + symbol); + goto fail; } + if (strong_try_module_get(fsa.owner)) + goto fail; preempt_enable(); return (void *)kernel_symbol_value(fsa.sym); +fail: + preempt_enable(); + return NULL; } EXPORT_SYMBOL_GPL(__symbol_get);