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 507413277A9; Fri, 17 Oct 2025 15:39:51 +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=1760715591; cv=none; b=kszdD2qzP9AWPqPaopCDeMM6z3NJBB/qTSZsyQWjzbvF805N/S7xcXIWzdGzJmEYayoH3FGMOPfiD0k4ze+fsjh9lvSJyaXmuH8R1C2lMYIdnfjehAl8jHVTFkTa/btQvQMiinPSDcReSSegQ1McmELiaWeQnQwZcDFqusy+nMk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760715591; c=relaxed/simple; bh=WttkTSmx6mpQQG21urS5YNukrnKUgEEQ5wyTduzazKQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZAPjDfkPYELr5fHdGA9AIgqAuHkZ5T0fQ/WvkXMD1c4iIzU4UXiGMsj8Nx0ZPi2mGNgsJzFRfJnnwROUElJt7C737NR0UEuxIQHJ+ZqnxxAc4NY5ICRTP5vxlZ5x2JH9zwiTGCxjBqvrFvFjlCeGXlg4taxjDIwhfucZ2iNWu5U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=BeF6k1sv; 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="BeF6k1sv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C852BC4CEE7; Fri, 17 Oct 2025 15:39:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1760715591; bh=WttkTSmx6mpQQG21urS5YNukrnKUgEEQ5wyTduzazKQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BeF6k1svjWI/1s0P62VvJ1PXMyOltiyczA9p9BlbCTwjiGfn7QHoAdmoVEskyXp8u fwnFUjMZkXPd+Bcg6Jvpnt6U/5rMUMWBV4CaWRDrZdASPwrtMKoswlE0iBF2dn2UAC 0XQakyi/SHUFwjLsB57IT5PKex36PWENnn91hL5Q= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Markus Elfring , Yang Erkun , Ming Lei , Yu Kuai , Li Chen , Jens Axboe Subject: [PATCH 6.17 236/371] loop: fix backing file reference leak on validation error Date: Fri, 17 Oct 2025 16:53:31 +0200 Message-ID: <20251017145210.620461106@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251017145201.780251198@linuxfoundation.org> References: <20251017145201.780251198@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 6.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Li Chen commit 98b7bf54338b797e3a11e8178ce0e806060d8fa3 upstream. loop_change_fd() and loop_configure() call loop_check_backing_file() to validate the new backing file. If validation fails, the reference acquired by fget() was not dropped, leaking a file reference. Fix this by calling fput(file) before returning the error. Cc: stable@vger.kernel.org Cc: Markus Elfring CC: Yang Erkun Cc: Ming Lei Cc: Yu Kuai Fixes: f5c84eff634b ("loop: Add sanity check for read/write_iter") Signed-off-by: Li Chen Reviewed-by: Ming Lei Reviewed-by: Yang Erkun Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- drivers/block/loop.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -551,8 +551,10 @@ static int loop_change_fd(struct loop_de return -EBADF; error = loop_check_backing_file(file); - if (error) + if (error) { + fput(file); return error; + } /* suppress uevents while reconfiguring the device */ dev_set_uevent_suppress(disk_to_dev(lo->lo_disk), 1); @@ -993,8 +995,10 @@ static int loop_configure(struct loop_de return -EBADF; error = loop_check_backing_file(file); - if (error) + if (error) { + fput(file); return error; + } is_loop = is_loop_device(file);