From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-184.mta0.migadu.com (out-184.mta0.migadu.com [91.218.175.184]) (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 729452D3ED2 for ; Thu, 23 Apr 2026 06:00:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.184 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776924037; cv=none; b=AffZcG9wbCVN0wokGvxd4VgQee8WQXGO5j+imWnD2KlM2XpV6IN/jV3MevPWVOrbrWvHAKRsfir4mXxYP41NGo2XJIeqoGTn/2Z/6Pr5gE0/W88hBesP9Ko8inol39Kl4uQI4SFaNblQFYHqNfuSLLseDjSWhhwejPTL22yhQUM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776924037; c=relaxed/simple; bh=Y7S0I53Mg4DYEFQeNIyERr6A6rh3rgmI4+Ci2lA9AwU=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=TdZrGaMEAPmJyFRllua62h75WQEgl8c48rF+KlA9gdwOxbDPtu2nlfxOlCRm/hekxi07cz9uq+opKO7aoQWDJe19HlnSw/OnzJ8U8j2jEHj082GHRgGJ6m6Lgosd7WmQO+pgobE3E0nPSvBYqBHLEwi6oFgNvuyrDAbjtlUO2tA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=YoFohIOE; arc=none smtp.client-ip=91.218.175.184 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="YoFohIOE" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1776924032; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=E4OPrLawMRVjhlxBvyuqSTW8+MhzcHg8GcecN28dJmE=; b=YoFohIOEB4NFHLZkkPRc9cgVrsKK0/Z7GLcLFTiDXZ+Pu3Ty5D4RVvG+Zvt3zasWsn0F+g fmCu2MKtAGGSl+c5ntpuXQpo08t+ud//diJ1Dxx8Uq6uGm8jsCwj/0wsjLIqyKGz/SFTJW mcFkl+MjHvQtXJLtAwFVe0mneXZsO/M= From: Youling Tang To: smfrench@gmail.com, linkinjeon@kernel.org, pc@manguebit.org, ronniesahlberg@gmail.com, sprasad@microsoft.com, tom@talpey.com, bharathsm@microsoft.com, senozhatsky@chromium.org, dhowells@redhat.com, chenxiaosong@chenxiaosong.com, gregkh@linuxfoundation.org Cc: linux-cifs@vger.kernel.org, youling.tang@linux.dev, Youling Tang , ChenXiaoSong Subject: [PATCH] smb/client: fix unaligned reads in wsl_to_fattr() Date: Thu, 23 Apr 2026 13:59:15 +0800 Message-ID: <20260423055915.695024-1-youling.tang@linux.dev> Precedence: bulk X-Mailing-List: linux-cifs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT From: Youling Tang See MS-FSCC 2.4.16. When multiple FILE_FULL_EA_INFORMATION data elements are present in the buffer, each MUST be aligned on a 4-byte boundary. When parsing WSL extended attributes, the code derives the value pointer at an offset of 7 (SMB2_WSL_XATTR_NAME_LEN + 1) from ea_data, the value sits at an unaligned offset. We should use get_unaligned_le32() or get_unaligned_le64() to get unaligned values. Link: https://lore.kernel.org/linux-cifs/77013349-ff89-4593-985d-520d967d2638@chenxiaosong.com/ Signed-off-by: Youling Tang Reviewed-by: ChenXiaoSong --- fs/smb/client/reparse.c | 6 +++--- fs/smb/client/reparse.h | 6 +++--- fs/smb/client/smb2pdu.h | 1 + 3 files changed, 7 insertions(+), 6 deletions(-) diff --git a/fs/smb/client/reparse.c b/fs/smb/client/reparse.c index cd1e1eaee67a..eebce954c5ce 100644 --- a/fs/smb/client/reparse.c +++ b/fs/smb/client/reparse.c @@ -1160,7 +1160,7 @@ static bool wsl_to_fattr(struct cifs_open_info_data *data, name = ea->ea_data; nlen = ea->ea_name_length; - v = (void *)((u8 *)ea->ea_data + ea->ea_name_length + 1); + v = (void *)((u8 *)name + nlen + 1); if (!strncmp(name, SMB2_WSL_XATTR_UID, nlen)) fattr->cf_uid = wsl_make_kuid(cifs_sb, v); @@ -1168,9 +1168,9 @@ static bool wsl_to_fattr(struct cifs_open_info_data *data, fattr->cf_gid = wsl_make_kgid(cifs_sb, v); else if (!strncmp(name, SMB2_WSL_XATTR_MODE, nlen)) { /* File type in reparse point tag and in xattr mode must match. */ - if (S_DT(fattr->cf_mode) != S_DT(le32_to_cpu(*(__le32 *)v))) + if (S_DT(fattr->cf_mode) != S_DT(get_unaligned_le32(v))) return false; - fattr->cf_mode = (umode_t)le32_to_cpu(*(__le32 *)v); + fattr->cf_mode = (umode_t)get_unaligned_le32(v); } else if (!strncmp(name, SMB2_WSL_XATTR_DEV, nlen)) { fattr->cf_rdev = reparse_mkdev(v); have_xattr_dev = true; diff --git a/fs/smb/client/reparse.h b/fs/smb/client/reparse.h index 0164dc47bdfd..653213a6b7e8 100644 --- a/fs/smb/client/reparse.h +++ b/fs/smb/client/reparse.h @@ -23,7 +23,7 @@ static inline dev_t reparse_mkdev(void *ptr) { - u64 v = le64_to_cpu(*(__le64 *)ptr); + u64 v = get_unaligned_le64(ptr); return MKDEV(v & 0xffffffff, v >> 32); } @@ -31,7 +31,7 @@ static inline dev_t reparse_mkdev(void *ptr) static inline kuid_t wsl_make_kuid(struct cifs_sb_info *cifs_sb, void *ptr) { - u32 uid = le32_to_cpu(*(__le32 *)ptr); + u32 uid = get_unaligned_le32(ptr); if (cifs_sb_flags(cifs_sb) & CIFS_MOUNT_OVERR_UID) return cifs_sb->ctx->linux_uid; @@ -41,7 +41,7 @@ static inline kuid_t wsl_make_kuid(struct cifs_sb_info *cifs_sb, static inline kgid_t wsl_make_kgid(struct cifs_sb_info *cifs_sb, void *ptr) { - u32 gid = le32_to_cpu(*(__le32 *)ptr); + u32 gid = get_unaligned_le32(ptr); if (cifs_sb_flags(cifs_sb) & CIFS_MOUNT_OVERR_GID) return cifs_sb->ctx->linux_gid; diff --git a/fs/smb/client/smb2pdu.h b/fs/smb/client/smb2pdu.h index 30d70097fe2f..6744606dab6c 100644 --- a/fs/smb/client/smb2pdu.h +++ b/fs/smb/client/smb2pdu.h @@ -211,6 +211,7 @@ struct compress_ioctl { * BB consider moving to a different header */ +/* See MS-FSCC 2.4.16 */ struct smb2_file_full_ea_info { /* encoding of response for level 15 */ __le32 next_entry_offset; __u8 flags; -- 2.53.0