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 3CCBC21D596; Wed, 25 Feb 2026 01:28:20 +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=1771982900; cv=none; b=K//nACPKsWt8hH0ZQF5TY6Nizbtcc0WSzzOfhMdhydqE+yLXOLrC3UYg0eSsDYXCtn4xyD1+9BdS/3sBAo7HYt5bxzLk0cAX/jfsp4EAGXguRTV4EEDxiJjOcqWX8ZRmA9N9Knpuxrp/IOEDWMTOMHvwYHZbSDcb2rxrcKFtmSM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771982900; c=relaxed/simple; bh=xBh2HZiUWuHGCLXiqY/Dq/RuF3ertNRVsFDEcc5VQYM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GqvQq/g22sAA4izPh77HJ9eea5fkj4z4kcx+kGZKIEFF2TA1ZLm37nU9s0nwXqFLskU0xwQGykKYdDepTAthNpJg6HzmCsIRHWlf4d+tbMJu8pDJ5TZZxF+7+YLQTdJcFx/85En0eMRbzkze1Ru5PtENKW7/R0l7LYqoUKIuA1A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=IjwobDym; 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="IjwobDym" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F11CDC116D0; Wed, 25 Feb 2026 01:28:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1771982900; bh=xBh2HZiUWuHGCLXiqY/Dq/RuF3ertNRVsFDEcc5VQYM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IjwobDymjlj/o641GXc9aOcWdIE35wDPkx7DbUB/j5d9bt27CGGn0gtKjCEa5WMCa p1gsZpImNQBHav7NePJ9TxIy/ulHMJBfqXFbFiHdyxR8bhUkgTLLQGWO4iBSK744GX F6DW16CVQOYhUf2bgGWDRwnRQIy3pxfeoHU95PDg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Salah Triki , Vineeth Vijayan , Heiko Carstens , Sasha Levin Subject: [PATCH 6.19 066/781] s390/cio: Fix device lifecycle handling in css_alloc_subchannel() Date: Tue, 24 Feb 2026 17:12:55 -0800 Message-ID: <20260225012401.323144332@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260225012359.695468795@linuxfoundation.org> References: <20260225012359.695468795@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 6.19-stable review patch. If anyone has any objections, please let me know. ------------------ 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 4c85df7a548ef..ac24e019020e8 100644 --- a/drivers/s390/cio/css.c +++ b/drivers/s390/cio/css.c @@ -235,7 +235,7 @@ struct subchannel *css_alloc_subchannel(struct subchannel_id schid, return sch; err: - kfree(sch); + put_device(&sch->dev); return ERR_PTR(ret); } -- 2.51.0