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 C255A522E for ; Sun, 9 Jul 2023 11:35:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 468F5C433C7; Sun, 9 Jul 2023 11:35:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1688902553; bh=fjnxqA4UUS6QAbFy+OFrg0tcWUdkF7DkC6nzAJIuEr0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=D6NDWKDEzdDuFu+0XSfssy0TIFMt4MjcU2fTKl/urSxQbhoOvn8jcns7DLGbz6COO 5hgzQsI95KRV68cDiFYgyddmnaeSgxBFu16Jh1hgmax2FObvN4h2Tqvb6GB+qK7I8C YIq0gd/LMqmLYzBvFtWZ5ApNj7dVsv9Uk4FF00GE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Joe Fradley , Sami Tolvanen , "Peter Zijlstra (Intel)" , Kees Cook , Nick Desaulniers , Masahiro Yamada , Sasha Levin Subject: [PATCH 6.3 417/431] kbuild: Disable GCOV for *.mod.o Date: Sun, 9 Jul 2023 13:16:05 +0200 Message-ID: <20230709111500.963546981@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230709111451.101012554@linuxfoundation.org> References: <20230709111451.101012554@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Sami Tolvanen [ Upstream commit 25a21fbb934a0d989e1858f83c2ddf4cfb2ebe30 ] With GCOV_PROFILE_ALL, Clang injects __llvm_gcov_* functions to each object file, including the *.mod.o. As we filter out CC_FLAGS_CFI for *.mod.o, the compiler won't generate type hashes for the injected functions, and therefore indirectly calling them during module loading trips indirect call checking. Enabling CFI for *.mod.o isn't sufficient to fix this issue after commit 0c3e806ec0f9 ("x86/cfi: Add boot time hash randomization"), as *.mod.o aren't processed by objtool, which means any hashes emitted there won't be randomized. Therefore, in addition to disabling CFI for *.mod.o, also disable GCOV, as the object files don't otherwise contain any executable code. Fixes: cf68fffb66d6 ("add support for Clang CFI") Reported-by: Joe Fradley Signed-off-by: Sami Tolvanen Acked-by: Peter Zijlstra (Intel) Reviewed-by: Kees Cook Reviewed-by: Nick Desaulniers Signed-off-by: Masahiro Yamada Signed-off-by: Sasha Levin --- scripts/Makefile.modfinal | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index 4703f652c0098..fc19f67039bda 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -23,7 +23,7 @@ modname = $(notdir $(@:.mod.o=)) part-of-module = y quiet_cmd_cc_o_c = CC [M] $@ - cmd_cc_o_c = $(CC) $(filter-out $(CC_FLAGS_CFI), $(c_flags)) -c -o $@ $< + cmd_cc_o_c = $(CC) $(filter-out $(CC_FLAGS_CFI) $(CFLAGS_GCOV), $(c_flags)) -c -o $@ $< %.mod.o: %.mod.c FORCE $(call if_changed_dep,cc_o_c) -- 2.39.2