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 4FE6136DA0B; Thu, 19 Mar 2026 16:44:51 +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=1773938691; cv=none; b=phDmYtVF0iGRVVcoENWJ6zjm0XK77O5+vlf58MXlIOkIS0g3n+brFf6fo/dZ54TvZy2RdH9mR4jo/JlLNDTEkBYJRs91k07XCQmhhrnnPPayqB5C7dwfL27kTp0qiPs0bNLW6TTXazJBRnBBeGHfSpJVQV5ZVRjCz8MRONQX2ps= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773938691; c=relaxed/simple; bh=QX8XFc1m9wVmSpF8FGoalOLGdqXx7hpSirHPF59hujI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aLaf6luI5D8nCOBV39iIxeE5LFUbDJyQalHqffCyXEupXcwr6zb6pS38DBptBgluD8YmZ7ql2Ilx2YY+B6ds8aK87ohkcFSsGQTtWnRjJlp2BWHM/E5Kk4blnRFSqTNV/vJh1ocxsOK3eJp+iL9dXj5w6j1DeUXMsFdjA3ZlHi4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DSIhfJRg; 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="DSIhfJRg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3E3B9C19424; Thu, 19 Mar 2026 16:44:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773938691; bh=QX8XFc1m9wVmSpF8FGoalOLGdqXx7hpSirHPF59hujI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DSIhfJRgnbrtDrfbVS+M8JJnCGz0Bce0tuX3MJOyckVfWF/sih8/Qg6V8/qmwyI9U kfqXmWhIfzNYoWJDqH3ZAE6FM+JsPx9Gq3+Szl9mEyNhqzWIbKnwd8mITrZTs8MsIo CQrlK7I0JU6tNQuuKARpPIVg2eQS2h9FhA7Am/nVNVuEC36i1tbY34f02OeDBcZm3n vHI3Zbq7obW14hUBKi1SYmyZ0aIzsLbbnTUVCyGeHmX8DE6/f7WK1C6omcSQaOWS2G 08QM30d+daIbJiokG/nl9bbjUDDJ2N18yEn6PfQSIlgjvWVLVR8hVkhbULFoYH9uzR Ix6NGTw3Kzv4g== From: Sasha Levin To: stable@vger.kernel.org Cc: Paulo Alcantara , David Howells , Henrique Carvalho , Tom Talpey , linux-cifs@vger.kernel.org, Steve French , Sasha Levin Subject: [PATCH 5.15.y] smb: client: fix atomic open with O_DIRECT & O_SYNC Date: Thu, 19 Mar 2026 12:44:48 -0400 Message-ID: <20260319164448.2729592-1-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <2026031705-crafty-showman-4909@gregkh> References: <2026031705-crafty-showman-4909@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Paulo Alcantara [ Upstream commit 4a7d2729dc99437dbb880a64c47828c0d191b308 ] When user application requests O_DIRECT|O_SYNC along with O_CREAT on open(2), CREATE_NO_BUFFER and CREATE_WRITE_THROUGH bits were missed in CREATE request when performing an atomic open, thus leading to potentially data integrity issues. Fix this by setting those missing bits in CREATE request when O_DIRECT|O_SYNC has been specified in cifs_do_create(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Paulo Alcantara (Red Hat) Reviewed-by: David Howells Acked-by: Henrique Carvalho Cc: Tom Talpey Cc: linux-cifs@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Steve French [ adapted file paths from fs/smb/client/ to fs/cifs/ ] Signed-off-by: Sasha Levin --- fs/cifs/cifsglob.h | 11 +++++++++++ fs/cifs/dir.c | 1 + fs/cifs/file.c | 17 +++-------------- 3 files changed, 15 insertions(+), 14 deletions(-) diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 68b9b382d44bf..7d044ce518f61 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -17,6 +17,7 @@ #include #include #include +#include #include "cifs_fs_sb.h" #include "cifsacl.h" #include @@ -2050,4 +2051,14 @@ static inline bool cifs_ses_exiting(struct cifs_ses *ses) return ret; } +static inline int cifs_open_create_options(unsigned int oflags, int opts) +{ + /* O_SYNC also has bit for O_DSYNC so following check picks up either */ + if (oflags & O_SYNC) + opts |= CREATE_WRITE_THROUGH; + if (oflags & O_DIRECT) + opts |= CREATE_NO_BUFFER; + return opts; +} + #endif /* _CIFS_GLOB_H */ diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c index 83c929dd6ed59..7cb7db5c44128 100644 --- a/fs/cifs/dir.c +++ b/fs/cifs/dir.c @@ -293,6 +293,7 @@ cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid, goto out; } + create_options |= cifs_open_create_options(oflags, create_options); /* * if we're not using unix extensions, see if we need to set * ATTR_READONLY on the create call diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 10bb1f9551887..0068c46cd0735 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -205,19 +205,13 @@ cifs_nt_open(const char *full_path, struct inode *inode, struct cifs_sb_info *ci *********************************************************************/ disposition = cifs_get_disposition(f_flags); - /* BB pass O_SYNC flag through on file attributes .. BB */ buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL); if (!buf) return -ENOMEM; - /* O_SYNC also has bit for O_DSYNC so following check picks up either */ - if (f_flags & O_SYNC) - create_options |= CREATE_WRITE_THROUGH; - - if (f_flags & O_DIRECT) - create_options |= CREATE_NO_BUFFER; + create_options |= cifs_open_create_options(f_flags, create_options); oparms.tcon = tcon; oparms.cifs_sb = cifs_sb; @@ -770,13 +764,8 @@ cifs_reopen_file(struct cifsFileInfo *cfile, bool can_flush) } desired_access = cifs_convert_flags(cfile->f_flags); - - /* O_SYNC also has bit for O_DSYNC so following check picks up either */ - if (cfile->f_flags & O_SYNC) - create_options |= CREATE_WRITE_THROUGH; - - if (cfile->f_flags & O_DIRECT) - create_options |= CREATE_NO_BUFFER; + create_options |= cifs_open_create_options(cfile->f_flags, + create_options); if (server->ops->get_lease_key) server->ops->get_lease_key(inode, &cfile->fid); -- 2.51.0