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 6B347383; Thu, 30 Jan 2025 14:16:32 +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=1738246592; cv=none; b=MAOU4W20IgitBxio+/dieBe7PoRV19YMzqnnRp6flyKnQtTRX8TCVMbMAhnZlfPDAChOPiugMD5INYkTZx7PC0nGyTIAvECo1GBYOiLz1RjoXznB98TTv22EJSHHhtI5n6JkPASmEpcU1P9WXE+HVEmqT81c0dNa64B8pHjfiWU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738246592; c=relaxed/simple; bh=XIGm+p+Qjicu9T40H8U7Vx5Ok5XMchM1PoIiAYqerVA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=TfYigKBdJXJsOpvTosTvQjAzptc5WZEJdLJV2iKRunPvODYhUgds9uB47+G6tRCxlOceF2Ex7AxJfwYmssi3o0GtqhPrvpPtSsl9JlieH0EeaAEYLvsCKvJ3tDH1U6NCdRMUNlZzSbR+vmpFEYrOh0YMmrQKOfiw60fWtK6k7ak= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=yhJVB+I0; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="yhJVB+I0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ED3C7C4CED2; Thu, 30 Jan 2025 14:16:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1738246592; bh=XIGm+p+Qjicu9T40H8U7Vx5Ok5XMchM1PoIiAYqerVA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yhJVB+I0zVFp4e/fpKvxS12dutbq2XqTRWe3iW646pRTCymALQtZt5OY/y6xMpHLd jGiVGkHdVYHYBclmTF77cuht33Q2CGgvCb6ZZzxbRlQOgmyPbcbT3CYkZQDWs1maII 5+XEXTxMzphwWZGAsqF+/CjImM/brBSYhjI9czZ4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Christian Brauner , Chuck Lever Subject: [PATCH 6.6 18/43] libfs: Fix simple_offset_rename_exchange() Date: Thu, 30 Jan 2025 14:59:25 +0100 Message-ID: <20250130133459.636074785@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250130133458.903274626@linuxfoundation.org> References: <20250130133458.903274626@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chuck Lever [ Upstream commit 23cdd0eed3f1fff3af323092b0b88945a7950d8e ] User space expects the replacement (old) directory entry to have the same directory offset after the rename. Suggested-by: Christian Brauner Fixes: a2e459555c5f ("shmem: stable directory offsets") Signed-off-by: Chuck Lever Link: https://lore.kernel.org/r/20240415152057.4605-2-cel@kernel.org Signed-off-by: Christian Brauner [ cel: adjusted to apply to origin/linux-6.6.y ] Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman --- fs/libfs.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) --- a/fs/libfs.c +++ b/fs/libfs.c @@ -294,6 +294,18 @@ int simple_offset_add(struct offset_ctx return 0; } +static int simple_offset_replace(struct offset_ctx *octx, struct dentry *dentry, + long offset) +{ + void *ret; + + ret = xa_store(&octx->xa, offset, dentry, GFP_KERNEL); + if (xa_is_err(ret)) + return xa_err(ret); + offset_set(dentry, offset); + return 0; +} + /** * simple_offset_remove - Remove an entry to a directory's offset map * @octx: directory offset ctx to be updated @@ -351,6 +363,9 @@ int simple_offset_empty(struct dentry *d * @new_dir: destination parent * @new_dentry: destination dentry * + * This API preserves the directory offset values. Caller provides + * appropriate serialization. + * * Returns zero on success. Otherwise a negative errno is returned and the * rename is rolled back. */ @@ -368,11 +383,11 @@ int simple_offset_rename_exchange(struct simple_offset_remove(old_ctx, old_dentry); simple_offset_remove(new_ctx, new_dentry); - ret = simple_offset_add(new_ctx, old_dentry); + ret = simple_offset_replace(new_ctx, old_dentry, new_index); if (ret) goto out_restore; - ret = simple_offset_add(old_ctx, new_dentry); + ret = simple_offset_replace(old_ctx, new_dentry, old_index); if (ret) { simple_offset_remove(new_ctx, old_dentry); goto out_restore; @@ -387,10 +402,8 @@ int simple_offset_rename_exchange(struct return 0; out_restore: - offset_set(old_dentry, old_index); - xa_store(&old_ctx->xa, old_index, old_dentry, GFP_KERNEL); - offset_set(new_dentry, new_index); - xa_store(&new_ctx->xa, new_index, new_dentry, GFP_KERNEL); + (void)simple_offset_replace(old_ctx, old_dentry, old_index); + (void)simple_offset_replace(new_ctx, new_dentry, new_index); return ret; }