From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 C97204DAF85; Thu, 17 Sep 2026 15:38:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789659529; cv=none; b=UL/eMt0Oaugx5V2RFZlEYkuyc9v/hz1K/ZZ5g8u8wub+B8yJwO2iIztQ9+6C+SA6GxdVhdS8SfKshDi1UmGcRGmQh8A6RWJ+nYzIZGS9fLM/5efscNdHsU/AxgdKApWqPXYomLNQ67F6zWuEqz3kjCTtEvGxsJ0rWh0JArx5UVI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789659529; c=relaxed/simple; bh=OFkdzJ7deq+LAF6a855h79aLdkkcuL5/ZkygQt0ClOA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jd9ALoA8wbuVF7zl66Q+OIeTz+j3GiezgbdLxqKJMNt08pFFddUYKCCMvfrUMX4Q7jOu5Pg1AwtGLdqYPnjuzixQ0PTRbhDlX6HnYi6m4LfjCKz27grAZJzK+m/6Mj0LjNCgat/dIO6xZ55ted76U2u7uhZQ6dD94sExsJgfMpQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=oqkdqIBK; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="oqkdqIBK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 103B41F0089C; Thu, 17 Sep 2026 15:38:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789659519; bh=/2ND6ZA4aZlJypp+gs4vW55whJ/Trfovama9j9IDAKA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=oqkdqIBKKkBHQ22YahYJFTGbgqzwbBdducxo3nP7BH3GNbi9/GNlD6F3UbXR6bPlD RGaq+SAp4b0EessNWOdv3YdL6BSZt7Ftt134dYNOxfJebcLbL3Sxr8yjwJVQDQ19s+ PiK5CQdGKqgqvXT9+8HU3TKdcSWJnuBqRKnXoCgg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alexandra Winter , Gerd Bayer , Jakub Kicinski , Sasha Levin Subject: [PATCH 7.2 283/733] s390/ism: folio_put() after error Date: Thu, 17 Sep 2026 16:09:51 +0100 Message-ID: <20260917151358.433415909@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260917151350.597953846@linuxfoundation.org> References: <20260917151350.597953846@linuxfoundation.org> User-Agent: quilt/0.69 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 7.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexandra Winter [ Upstream commit 907a56ab3eb8a58500a58daa76087f17bb2b6826 ] dmb->cpu_addr was allocated via folio_alloc(). Use folio_put() instead of kfree() in the error exit of ism_alloc_dmb() to avoid slab allocator corruption. While at it, reset dmb->cpu_addr after folio_put to avoid unintentional UAF by future callers. Fixes: 83781384a96b ("s390/ism: Properly fix receive message buffer allocation") Signed-off-by: Alexandra Winter Reviewed-by: Gerd Bayer Link: https://patch.msgid.link/20260902143733.433574-1-wintera@linux.ibm.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/s390/net/ism_drv.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/s390/net/ism_drv.c b/drivers/s390/net/ism_drv.c index 242da20f27e0e..035b233abb4e9 100644 --- a/drivers/s390/net/ism_drv.c +++ b/drivers/s390/net/ism_drv.c @@ -231,6 +231,7 @@ static void ism_free_dmb(struct ism_dev *ism, struct dibs_dmb *dmb) dma_unmap_page(&ism->pdev->dev, dmb->dma_addr, dmb->dmb_len, DMA_FROM_DEVICE); folio_put(virt_to_folio(dmb->cpu_addr)); + dmb->cpu_addr = NULL; } static int ism_alloc_dmb(struct ism_dev *ism, struct dibs_dmb *dmb) @@ -274,7 +275,8 @@ static int ism_alloc_dmb(struct ism_dev *ism, struct dibs_dmb *dmb) return 0; out_free: - kfree(dmb->cpu_addr); + folio_put(folio); + dmb->cpu_addr = NULL; out_bit: clear_bit(dmb->idx, ism->sba_bitmap); return rc; -- 2.53.0