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 C9B552D5940; Tue, 17 Mar 2026 17:19:44 +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=1773767984; cv=none; b=KPpFaCHxM//3pbY2W/h/BBmZYHwiCm8vg1adkBvvzdd9BZpvMxhaOef1AkVnywnz8LJ9iT96T7XXnXBQC4U9I2gby819YRPnC/cDanRndFPlvMudAmovsABMqUuHCvlztpfokK+bYwSuqqw8oFr/oMAITy5SIeuvQ6nZVI/2tSQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773767984; c=relaxed/simple; bh=3sUQHDlffL/NO6K8ZQJKwwDGz8sU6riixgEy6njWVS0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=px/MFd2gHMGyCXzZUIagsTLQ6+NfA+xWSv47Q+pcydg7EvYW9DPtwjzyOrq0OkPXtb5Y2SUjhZ94s12Ysn2j4CWoUo1vp/h0/yPXzgbp6HB0IWpuVRCrG4gk9d4kezP5Q2uTpo4YsuXBtZ4jW66SuYNPzqDk3DqW7GEsM+zYY1I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=oSBoxlur; 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="oSBoxlur" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 00C9BC4CEF7; Tue, 17 Mar 2026 17:19:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1773767984; bh=3sUQHDlffL/NO6K8ZQJKwwDGz8sU6riixgEy6njWVS0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oSBoxlurych6ssc5IsgqOrXMYvOH3bZRKWhRxahVz/CPZlKXvUFTyZhyoUNkb4B/4 w+oesdjAgFCZarV+OOo+NCARqKc4AjcvJh2K4VBvUHYf+7L0DQxsBs9EN5GdCS6R/U FMom4a2389nr2TcxV7FHjJ24AUgVpy+kJ+d7Eb20= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Darrick J. Wong" , Christoph Hellwig , Carlos Maiolino , Christian Brauner Subject: [PATCH 6.18 204/333] iomap: reject delalloc mappings during writeback Date: Tue, 17 Mar 2026 17:33:53 +0100 Message-ID: <20260317163006.923016024@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260317162959.345812316@linuxfoundation.org> References: <20260317162959.345812316@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Darrick J. Wong commit d320f160aa5ff36cdf83c645cca52b615e866e32 upstream. Filesystems should never provide a delayed allocation mapping to writeback; they're supposed to allocate the space before replying. This can lead to weird IO errors and crashes in the block layer if the filesystem is being malicious, or if it hadn't set iomap->dev because it's a delalloc mapping. Fix this by failing writeback on delalloc mappings. Currently no filesystems actually misbehave in this manner, but we ought to be stricter about things like that. Cc: stable@vger.kernel.org # v5.5 Fixes: 598ecfbaa742ac ("iomap: lift the xfs writeback code to iomap") Signed-off-by: Darrick J. Wong Link: https://patch.msgid.link/20260302173002.GL13829@frogsfrogsfrogs Reviewed-by: Christoph Hellwig Reviewed-by: Carlos Maiolino Signed-off-by: Christian Brauner Signed-off-by: Greg Kroah-Hartman --- fs/iomap/ioend.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) --- a/fs/iomap/ioend.c +++ b/fs/iomap/ioend.c @@ -163,17 +163,18 @@ ssize_t iomap_add_to_ioend(struct iomap_ WARN_ON_ONCE(!folio->private && map_len < dirty_len); switch (wpc->iomap.type) { - case IOMAP_INLINE: - WARN_ON_ONCE(1); - return -EIO; + case IOMAP_UNWRITTEN: + ioend_flags |= IOMAP_IOEND_UNWRITTEN; + break; + case IOMAP_MAPPED: + break; case IOMAP_HOLE: return map_len; default: - break; + WARN_ON_ONCE(1); + return -EIO; } - if (wpc->iomap.type == IOMAP_UNWRITTEN) - ioend_flags |= IOMAP_IOEND_UNWRITTEN; if (wpc->iomap.flags & IOMAP_F_SHARED) ioend_flags |= IOMAP_IOEND_SHARED; if (folio_test_dropbehind(folio))