From nobody Tue Dec 16 16:41:11 2025 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 9F21EC7618E for ; Mon, 24 Apr 2023 04:51:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230474AbjDXEvy (ORCPT ); Mon, 24 Apr 2023 00:51:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57726 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230450AbjDXEvu (ORCPT ); Mon, 24 Apr 2023 00:51:50 -0400 Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 35D442D48; Sun, 23 Apr 2023 21:51:46 -0700 (PDT) X-UUID: 886b32d10673477db2b5947a0d3fb511-20230424 X-CID-CACHE: Type:Local,Time:202304241246+08,HitQuantity:1 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.22,REQID:b652d489-1d09-4d14-a81f-45cbe1d5f83f,IP:5,U RL:0,TC:0,Content:-25,EDM:0,RT:0,SF:-15,FILE:0,BULK:0,RULE:Release_Ham,ACT ION:release,TS:-35 X-CID-INFO: VERSION:1.1.22,REQID:b652d489-1d09-4d14-a81f-45cbe1d5f83f,IP:5,URL :0,TC:0,Content:-25,EDM:0,RT:0,SF:-15,FILE:0,BULK:0,RULE:Release_Ham,ACTIO N:release,TS:-35 X-CID-META: VersionHash:120426c,CLOUDID:c96be9eb-db6f-41fe-8b83-13fe7ed1ef52,B ulkID:nil,BulkQuantity:0,Recheck:0,SF:24|17|19|44|38|102,TC:nil,Content:0, EDM:-3,IP:-2,URL:0,File:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0 X-CID-BVR: 0 X-CID-BAS: 0,_,0,_ X-UUID: 886b32d10673477db2b5947a0d3fb511-20230424 X-User: gehao@kylinos.cn Received: from localhost.localdomain [(116.128.244.169)] by mailgw (envelope-from ) (Generic MTA) with ESMTP id 2085282739; Mon, 24 Apr 2023 12:51:39 +0800 From: Hao Ge To: viro@zeniv.linux.org.uk, brauner@kernel.org Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, gehao618@163.com, Hao Ge Subject: [PATCH V2] fs: fix undefined behavior in bit shift for SB_NOUSER Date: Mon, 24 Apr 2023 12:51:22 +0800 Message-Id: <20230424045122.370511-1-gehao@kylinos.cn> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230424030005.363457-1-gehao@kylinos.cn> References: <20230424030005.363457-1-gehao@kylinos.cn> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 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 fs/nsfs.c:306:32 left shift of 1 by 31 places cannot be represented in type 'int' CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.3.0-rc4+ #2 Call trace: dump_backtrace+0x134/0x1e0 show_stack+0x2c/0x3c dump_stack_lvl+0xb0/0xd4 dump_stack+0x14/0x1c ubsan_epilogue+0xc/0x3c __ubsan_handle_shift_out_of_bounds+0xb0/0x14c nsfs_init+0x4c/0xb0 start_kernel+0x38c/0x738 __primary_switched+0xbc/0xc4 Fixes: e462ec50cb5f ("VFS: Differentiate mount flags (MS_*) from internal s= uperblock flags") Signed-off-by: Hao Ge --- v2: add Fixes for changelog --- include/linux/fs.h | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/include/linux/fs.h b/include/linux/fs.h index c85916e9f7db..86ab23a05b61 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1069,19 +1069,19 @@ extern int send_sigurg(struct fown_struct *fown); #define SB_NOATIME 1024 /* Do not update access times. */ #define SB_NODIRATIME 2048 /* Do not update directory access times */ #define SB_SILENT 32768 -#define SB_POSIXACL (1<<16) /* VFS does not apply the umask */ -#define SB_INLINECRYPT (1<<17) /* Use blk-crypto for encrypted files */ -#define SB_KERNMOUNT (1<<22) /* this is a kern_mount call */ -#define SB_I_VERSION (1<<23) /* Update inode I_version field */ -#define SB_LAZYTIME (1<<25) /* Update the on-disk [acm]times lazily */ +#define SB_POSIXACL (1U<<16) /* VFS does not apply the umask */ +#define SB_INLINECRYPT (1U<<17) /* Use blk-crypto for encrypted files */ +#define SB_KERNMOUNT (1U<<22) /* this is a kern_mount call */ +#define SB_I_VERSION (1U<<23) /* Update inode I_version field */ +#define SB_LAZYTIME (1U<<25) /* Update the on-disk [acm]times lazily */ =20 /* These sb flags are internal to the kernel */ -#define SB_SUBMOUNT (1<<26) -#define SB_FORCE (1<<27) -#define SB_NOSEC (1<<28) -#define SB_BORN (1<<29) -#define SB_ACTIVE (1<<30) -#define SB_NOUSER (1<<31) +#define SB_SUBMOUNT (1U<<26) +#define SB_FORCE (1U<<27) +#define SB_NOSEC (1U<<28) +#define SB_BORN (1U<<29) +#define SB_ACTIVE (1U<<30) +#define SB_NOUSER (1U<<31) =20 /* These flags relate to encoding and casefolding */ #define SB_ENC_STRICT_MODE_FL (1 << 0) --=20 2.25.1 No virus found Checked by Hillstone Network AntiVirus