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 CDC81C4332F for ; Mon, 14 Nov 2022 12:48:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237221AbiKNMsL (ORCPT ); Mon, 14 Nov 2022 07:48:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39584 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237256AbiKNMr6 (ORCPT ); Mon, 14 Nov 2022 07:47:58 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3F855EAA for ; Mon, 14 Nov 2022 04:47:57 -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 ams.source.kernel.org (Postfix) with ESMTPS id DBCA3B80EBC for ; Mon, 14 Nov 2022 12:47:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D14CAC433D7; Mon, 14 Nov 2022 12:47:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1668430074; bh=IGVuUwPgjY9AaZnR2/MWF4Zw2btBxNpZ4NYH1Jhzx/E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Xo/HFu0gKgZvG7AfVuvq+J7XVpAczCwyiickVU5kSiXT/i8XdEQLXDz7NYXZrE+Qq NDmxwyY9+EtlkkyGJ/woGSHRWr1PIKgWQqlYf8iTASiiKWKdeGwoSvJdH3VD9g/4J1 FebeBK+DD8assqDzz87N8b6UEjwJKox8CZtmGfyw= 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 5.10 21/95] capabilities: fix undefined behavior in bit shift for CAP_TO_MASK Date: Mon, 14 Nov 2022 13:45:15 +0100 Message-Id: <20221114124443.394687519@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221114124442.530286937@linuxfoundation.org> References: <20221114124442.530286937@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 2ddb4226cd23..43a44538ec8d 100644 --- a/include/uapi/linux/capability.h +++ b/include/uapi/linux/capability.h @@ -427,7 +427,7 @@ 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