commit
71e6864eacbef0b2645ca043cdfbac272cb6cea3 upstream.
Linux allows doing a flush/fsync on a file open for read-only,
but the protocol does not allow that. If the file passed in
on the flush is read-only try to find a writeable handle for
the same inode, if that is not possible skip sending the
fsync call to the server to avoid breaking the apps.
Reported-by: Julian Sikorski <belegdol@gmail.com>
Tested-by: Julian Sikorski <belegdol@gmail.com>
Suggested-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tcon = tlink_tcon(smbfile->tlink);
if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
server = tcon->ses->server;
tcon = tlink_tcon(smbfile->tlink);
if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
server = tcon->ses->server;
- if (server->ops->flush)
- rc = server->ops->flush(xid, tcon, &smbfile->fid);
- else
+ if (server->ops->flush == NULL) {
+ goto strict_fsync_exit;
+ }
+
+ if ((OPEN_FMODE(smbfile->f_flags) & FMODE_WRITE) == 0) {
+ smbfile = find_writable_file(CIFS_I(inode), FIND_WR_ANY);
+ if (smbfile) {
+ rc = server->ops->flush(xid, tcon, &smbfile->fid);
+ cifsFileInfo_put(smbfile);
+ } else
+ cifs_dbg(FYI, "ignore fsync for file not open for write\n");
+ } else
+ rc = server->ops->flush(xid, tcon, &smbfile->fid);
free_xid(xid);
return rc;
}
free_xid(xid);
return rc;
}
struct cifs_tcon *tcon;
struct TCP_Server_Info *server;
struct cifsFileInfo *smbfile = file->private_data;
struct cifs_tcon *tcon;
struct TCP_Server_Info *server;
struct cifsFileInfo *smbfile = file->private_data;
+ struct inode *inode = file_inode(file);
struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
rc = file_write_and_wait_range(file, start, end);
struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
rc = file_write_and_wait_range(file, start, end);
tcon = tlink_tcon(smbfile->tlink);
if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
server = tcon->ses->server;
tcon = tlink_tcon(smbfile->tlink);
if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
server = tcon->ses->server;
- if (server->ops->flush)
- rc = server->ops->flush(xid, tcon, &smbfile->fid);
- else
+ if (server->ops->flush == NULL) {
+ goto fsync_exit;
+ }
+
+ if ((OPEN_FMODE(smbfile->f_flags) & FMODE_WRITE) == 0) {
+ smbfile = find_writable_file(CIFS_I(inode), FIND_WR_ANY);
+ if (smbfile) {
+ rc = server->ops->flush(xid, tcon, &smbfile->fid);
+ cifsFileInfo_put(smbfile);
+ } else
+ cifs_dbg(FYI, "ignore fsync for file not open for write\n");
+ } else
+ rc = server->ops->flush(xid, tcon, &smbfile->fid);
free_xid(xid);
return rc;
}
free_xid(xid);
return rc;
}