From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31F1EC4332F for ; Wed, 23 Nov 2022 09:10:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237175AbiKWJKp (ORCPT ); Wed, 23 Nov 2022 04:10:45 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51202 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237198AbiKWJKh (ORCPT ); Wed, 23 Nov 2022 04:10:37 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 475F6106113 for ; Wed, 23 Nov 2022 01:10:30 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D1C0C61B14 for ; Wed, 23 Nov 2022 09:10:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B0D3EC433D6; Wed, 23 Nov 2022 09:10:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1669194629; bh=WH18cPsKWwF+LC7xjVD+TnfDBYhZyD/dORe/weZmqmA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WxSrqJ57W/cmjhrCeSUrJDu4SwPYZO2ZbgG34nEXF+RxlAZybvfVE77Jj1FWaYa56 mb0kpVmt3UGn9MAhCXyRnY4o4ado5EJ2JNO74YPH6jnr/qJhUkoj6IrxjaIrmZtwg8 i5s/PhMZdg23VZB0tNwASy9TQGM1P8Z1Wh6yyOGE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Gaosheng Cui , "Andrew G. Morgan" , Serge Hallyn , Paul Moore , Sasha Levin Subject: [PATCH 5.4 017/156] capabilities: fix undefined behavior in bit shift for CAP_TO_MASK Date: Wed, 23 Nov 2022 09:49:34 +0100 Message-Id: <20221123084558.517935230@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221123084557.816085212@linuxfoundation.org> References: <20221123084557.816085212@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Gaosheng Cui [ Upstream commit 46653972e3ea64f79e7f8ae3aa41a4d3fdb70a13 ] Shifting signed 32-bit value by 31 bits is undefined, so changing significant bit to unsigned. The UBSAN warning calltrace like below: UBSAN: shift-out-of-bounds in security/commoncap.c:1252:2 left shift of 1 by 31 places cannot be represented in type 'int' Call Trace: dump_stack_lvl+0x7d/0xa5 dump_stack+0x15/0x1b ubsan_epilogue+0xe/0x4e __ubsan_handle_shift_out_of_bounds+0x1e7/0x20c cap_task_prctl+0x561/0x6f0 security_task_prctl+0x5a/0xb0 __x64_sys_prctl+0x61/0x8f0 do_syscall_64+0x58/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: e338d263a76a ("Add 64-bit capability support to the kernel") Signed-off-by: Gaosheng Cui Acked-by: Andrew G. Morgan Reviewed-by: Serge Hallyn Signed-off-by: Paul Moore Signed-off-by: Sasha Levin --- include/uapi/linux/capability.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/uapi/linux/capability.h b/include/uapi/linux/capability.h index 240fdb9a60f6..6e0d68e841cd 100644 --- a/include/uapi/linux/capability.h +++ b/include/uapi/linux/capability.h @@ -376,7 +376,7 @@ struct vfs_ns_cap_data { */ #define CAP_TO_INDEX(x) ((x) >> 5) /* 1 << 5 == bits in __u32 */ -#define CAP_TO_MASK(x) (1 << ((x) & 31)) /* mask for indexed __u32 */ +#define CAP_TO_MASK(x) (1U << ((x) & 31)) /* mask for indexed __u32 */ #endif /* _UAPI_LINUX_CAPABILITY_H */ -- 2.35.1