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 24C8D36C9EB for ; Sat, 28 Feb 2026 18:11:51 +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=1772302311; cv=none; b=H0zvQGDufgLO29Ao//+a0xxjX4qtQR3blSLsrdY70SSJwrc2f2T4Sl8bL6lRfubMY3WDmvnsUPynZDJPtYu9HjQgWeIlQfuba3Q4wEB6JTp207MB0fyY3rgzA48tP8RDVmbr7eZscgMlt9nuDQ6fpdpUsB/OcJlbxAGYJfUYrBQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302311; c=relaxed/simple; bh=RD/GpCQ36bV2Ee+VnF53WUW8n94fM7DX5JEwJhm1X3o=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FTAlmCMzoPplHcyo0abUFEenpOFEyp2Oj7XYqzbsjx+EusF1Jy5/K2hLtOcqulI8WHfd3Uxf+eZbYVpGoZEyQi6Pztu9CGbwtNZdnLWGNxMNF3Zuuc3y/7cNGufLqhMZylaBUBiIIeO2bV9BN8Jmwci8qQSMuXbr4tIRjCUGb8g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nGpPlM2h; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nGpPlM2h" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 70D35C116D0; Sat, 28 Feb 2026 18:11:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302311; bh=RD/GpCQ36bV2Ee+VnF53WUW8n94fM7DX5JEwJhm1X3o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nGpPlM2hNKg2f4I7iHn0wzQbLgpGqGT8N+UOLzc/b9z8Sg0Kn8xr1JPeHnbo46wQ5 U4qE4vBW9pDP8mfpK0aG937Ns3K48u3QeRUvzdmntz8EfkCxRf/Kinqq/WL6vdiE6f /XWTg9fw/gSf5SxDp6tE8ZIsgyhjw01rJwCc3nEQWA/cZ3rEkc2THOxZwBPExkP6Gb esyHNNUgPJnHVH9xa+yqJealLMBQc8IUv+tce4vOiPjT9YgSKnJPP6C8E4DPr3U3Uw tztbFgmOQoXt4E1nDwTSeYrEaQVmFf/nic6uO/dXzw0adQCHFkRMmXGEVzAcALUBoR 5uSMzYaNjhcVg== From: Sasha Levin To: patches@lists.linux.dev Cc: Salah Triki , Vineeth Vijayan , Heiko Carstens , Sasha Levin Subject: [PATCH 6.1 027/232] s390/cio: Fix device lifecycle handling in css_alloc_subchannel() Date: Sat, 28 Feb 2026 13:08:00 -0500 Message-ID: <20260228181127.1592657-27-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228181127.1592657-1-sashal@kernel.org> References: <20260228181127.1592657-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Salah Triki [ Upstream commit f65c75b0b9b5a390bc3beadcde0a6fbc3ad118f7 ] `css_alloc_subchannel()` calls `device_initialize()` before setting up the DMA masks. If `dma_set_coherent_mask()` or `dma_set_mask()` fails, the error path frees the subchannel structure directly, bypassing the device model reference counting. Once `device_initialize()` has been called, the embedded struct device must be released via `put_device()`, allowing the release callback to free the container structure. Fix the error path by dropping the initial device reference with `put_device()` instead of calling `kfree()` directly. This ensures correct device lifetime handling and avoids potential use-after-free or double-free issues. Fixes: e5dcf0025d7af ("s390/css: move subchannel lock allocation") Signed-off-by: Salah Triki Reviewed-by: Vineeth Vijayan Signed-off-by: Heiko Carstens Signed-off-by: Sasha Levin --- drivers/s390/cio/css.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c index 98a14c1f3d672..85c1734ebfe88 100644 --- a/drivers/s390/cio/css.c +++ b/drivers/s390/cio/css.c @@ -247,7 +247,7 @@ struct subchannel *css_alloc_subchannel(struct subchannel_id schid, err_lock: kfree(sch->lock); err: - kfree(sch); + put_device(&sch->dev); return ERR_PTR(ret); } -- 2.51.0