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 579FC1272DD; Sun, 24 Mar 2024 22:52:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711320764; cv=none; b=jvRmzPtLl3AMdVgZuafOud89+ta/1eRk88K5hbzZSM7B7pLhR8Yte/2AYf1rZX7ZQGYwN9L8EFaJ6QUBUbrEMWdBHiRwdjmlIUWNuHSGSQJAImfoMR9PpBeBdedTQvqF/xZOKbVlr9DMabt+CKhAJow4zqyMJlu5n1VUwrUWDAg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711320764; c=relaxed/simple; bh=YNZbHaV8JW7SkCNxUeXarPC6P7Kv6wqn4pMipRrje38=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OcS0VOjpRrwu4GsHqwtiQehORo7P6CsDS89zcDG3sJHui1H90WO2xf633zgHed4RjRE0bhQG5waiqYLvfK08KQxNYZ6TLJ74BAMNybBf1Mwo75j8tMQg55NvHIj0HfeWes1/ESPLSXr24akx4U0T0z8uS+Rs1+FFZZExhmJC0NA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=OG3IODSy; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="OG3IODSy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7EDE2C43399; Sun, 24 Mar 2024 22:52:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711320763; bh=YNZbHaV8JW7SkCNxUeXarPC6P7Kv6wqn4pMipRrje38=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OG3IODSysIr0OO2eoVcUOfFdTvHYbT2s6aaDWWJm8CS/MXcRtj5GPdfDr/Z62PjUJ 3yKL9zIzY70080i2V7fu380UJWChmRNvTDgTVjYN27viRbEkgtXREJB9hnzseTr1JW 0ioXX9GalFu4tzM783n4p7Zyyn1HQRw5nUohJx0EGSxvTC1GhWfREQGdIi2mndJlsq Jt59IjlmSQ17roFHKHTxwy2C6F1JZHWpU3VQflODl/4zqxORfUYK0XnQxwM2cF1fHo 6hBZR5cKOUdm5570yA6GZSXl0NSvzlzzQVurBdTvcYo3kdBvGMM62gfcnxuKEyBPMr a+0LLjpgIrWmg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Josh Poimboeuf , kernel test robot , Kees Cook , Sasha Levin Subject: [PATCH 6.7 327/713] objtool: Fix UNWIND_HINT_{SAVE,RESTORE} across basic blocks Date: Sun, 24 Mar 2024 18:40:53 -0400 Message-ID: <20240324224720.1345309-328-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240324224720.1345309-1-sashal@kernel.org> References: <20240324224720.1345309-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Josh Poimboeuf [ Upstream commit 10b4c4bce3f5541f54bcc2039720b11d2bc96d79 ] If SAVE and RESTORE unwind hints are in different basic blocks, and objtool sees the RESTORE before the SAVE, it errors out with: vmlinux.o: warning: objtool: vmw_port_hb_in+0x242: objtool isn't smart enough to handle this CFI save/restore combo In such a case, defer following the RESTORE block until the straight-line path gets followed later. Fixes: 8faea26e6111 ("objtool: Re-add UNWIND_HINT_{SAVE_RESTORE}") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202402240702.zJFNmahW-lkp@intel.com/ Signed-off-by: Josh Poimboeuf Link: https://lore.kernel.org/r/20240227073527.avcm5naavbv3cj5s@treble Signed-off-by: Kees Cook Signed-off-by: Sasha Levin --- tools/objtool/check.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/tools/objtool/check.c b/tools/objtool/check.c index e94756e09ca9f..167603f839851 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -3620,6 +3620,18 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, } if (!save_insn->visited) { + /* + * If the restore hint insn is at the + * beginning of a basic block and was + * branched to from elsewhere, and the + * save insn hasn't been visited yet, + * defer following this branch for now. + * It will be seen later via the + * straight-line path. + */ + if (!prev_insn) + return 0; + WARN_INSN(insn, "objtool isn't smart enough to handle this CFI save/restore combo"); return 1; } -- 2.43.0