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 X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D78B4C43215 for ; Fri, 15 Nov 2019 11:33:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AB5F72072D for ; Fri, 15 Nov 2019 11:33:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="tdUiHY5S" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727411AbfKOLdS (ORCPT ); Fri, 15 Nov 2019 06:33:18 -0500 Received: from mail-wm1-f67.google.com ([209.85.128.67]:38589 "EHLO mail-wm1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727210AbfKOLdR (ORCPT ); Fri, 15 Nov 2019 06:33:17 -0500 Received: by mail-wm1-f67.google.com with SMTP id z19so10036872wmk.3; Fri, 15 Nov 2019 03:33:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=SjsBoxZpnXuWdt5imWu8R6Un/MP6XwVLVHRk4CSDF/M=; b=tdUiHY5SmMTUG2L3aFxXNDKQdhB7lnfDGZsDbsWLGlrr8d4u+1+RmtqCU529gizxfP oxEaEUPR2nfi5KfBqm+Ix1qdIZdyYS1YIwTC9Nr6t/b6/r9k4q/YkKHR4sTYM5LIepX4 TdyTU3TZfV7PuddDi9LsKrFPaHzz6ogIn6AjV20fbW4SmQr0SqXj4lFKRiGsYsTPfhpr Tz1/g8UvEY8QnXr+xISfTjx8f37/TXjZhN5zvG1OmHgODHVxXM915EYW2krCCO5+t+fI iym2fe4Ib6xzGbT/zZegL68rL0zirpJyd1JW1cUKochKXUtjWgYXxvy+szcT6OH+VMRt EQmQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=SjsBoxZpnXuWdt5imWu8R6Un/MP6XwVLVHRk4CSDF/M=; b=ZW4XXVbB1FCvHnqnmVMr/NwbWpcQwrav9PBlKH6KLhGfjmJA1UkeZqHYzaygGEqv++ ygF5MfM3t/ad91CDT0U8A71eCAoEFkpU3XtmWFmdRIemnerothFuH1RpB9/mNg8wjEJ2 baDPra8U4+QqQLQC0u0paePaDHz3CHE6xL9apU7kOquHgNXoZI6HAkVFglOFdJWmR2As ycx9jH+GhFBZAVxVjKWNhPNYEUBaBmDH6avl+hzait27EcbtPf8DhW+8IdRO5fTOG5UA L4aL/R4N975A9KiyxyqtzE9wE1nVijlTqY37te0xQUv9zDKF8o9L7rrI8n1j85up7vmm Xbgw== X-Gm-Message-State: APjAAAVkh2AdxV6CYJWAuokrsFC+VwggIkNnfi2SxcVMMr8Pdtl/tyOd URPwzBTA8JLr0rzxHItKFN4= X-Google-Smtp-Source: APXvYqwKaHpwCHnWS2MrArQV7wV0TaKtxj+KHQFJd8QT+3u5XoweyB8dRbd5Sp6Uh31le+1N0TIi0w== X-Received: by 2002:a1c:410a:: with SMTP id o10mr14092912wma.117.1573817594193; Fri, 15 Nov 2019 03:33:14 -0800 (PST) Received: from localhost.localdomain ([94.230.83.228]) by smtp.gmail.com with ESMTPSA id l4sm9225181wme.4.2019.11.15.03.33.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 15 Nov 2019 03:33:13 -0800 (PST) From: Amir Goldstein To: Miklos Szeredi Cc: Al Viro , linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v2 2/2] ovl: don't use a temp buf for encoding real fh Date: Fri, 15 Nov 2019 13:33:04 +0200 Message-Id: <20191115113304.16209-3-amir73il@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191115113304.16209-1-amir73il@gmail.com> References: <20191115113304.16209-1-amir73il@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org We can allocate maximum fh size and encode into it directly. Suggested-by: Al Viro Signed-off-by: Amir Goldstein --- fs/overlayfs/copy_up.c | 37 ++++++++++++++++--------------------- 1 file changed, 16 insertions(+), 21 deletions(-) diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index 7f744a9541e5..6220642fe113 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -227,13 +227,17 @@ int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat) struct ovl_fh *ovl_encode_real_fh(struct dentry *real, bool is_upper) { struct ovl_fh *fh; - int fh_type, fh_len, dwords; - void *buf; + int fh_type, dwords; int buflen = MAX_HANDLE_SZ; uuid_t *uuid = &real->d_sb->s_uuid; + int err; - buf = kmalloc(buflen, GFP_KERNEL); - if (!buf) + /* Make sure the real fid stays 32bit aligned */ + BUILD_BUG_ON(OVL_FH_FID_OFFSET % 4); + BUILD_BUG_ON(MAX_HANDLE_SZ + OVL_FH_FID_OFFSET > 255); + + fh = kzalloc(buflen + OVL_FH_FID_OFFSET, GFP_KERNEL); + if (!fh) return ERR_PTR(-ENOMEM); /* @@ -242,24 +246,14 @@ struct ovl_fh *ovl_encode_real_fh(struct dentry *real, bool is_upper) * the price or reconnecting the dentry. */ dwords = buflen >> 2; - fh_type = exportfs_encode_fh(real, buf, &dwords, 0); + fh_type = exportfs_encode_fh(real, (void *)fh->fb.fid, &dwords, 0); buflen = (dwords << 2); - fh = ERR_PTR(-EIO); + err = -EIO; if (WARN_ON(fh_type < 0) || WARN_ON(buflen > MAX_HANDLE_SZ) || WARN_ON(fh_type == FILEID_INVALID)) - goto out; - - /* Make sure the real fid stays 32bit aligned */ - BUILD_BUG_ON(OVL_FH_FID_OFFSET % 4); - BUILD_BUG_ON(MAX_HANDLE_SZ + OVL_FH_FID_OFFSET > 255); - fh_len = OVL_FH_FID_OFFSET + buflen; - fh = kzalloc(fh_len, GFP_KERNEL); - if (!fh) { - fh = ERR_PTR(-ENOMEM); - goto out; - } + goto out_err; fh->fb.version = OVL_FH_VERSION; fh->fb.magic = OVL_FH_MAGIC; @@ -273,13 +267,14 @@ struct ovl_fh *ovl_encode_real_fh(struct dentry *real, bool is_upper) */ if (is_upper) fh->fb.flags |= OVL_FH_FLAG_PATH_UPPER; - fh->fb.len = fh_len - OVL_FH_WIRE_OFFSET; + fh->fb.len = sizeof(fh->fb) + buflen; fh->fb.uuid = *uuid; - memcpy(fh->fb.fid, buf, buflen); -out: - kfree(buf); return fh; + +out_err: + kfree(fh); + return ERR_PTR(err); } int ovl_set_origin(struct dentry *dentry, struct dentry *lower, -- 2.17.1