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 AD34243CEF3; Tue, 13 Oct 2026 12:17:13 +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=1791893835; cv=none; b=uSR38YdzgoSO8B6XOqfnNqtkR30q5u73OJOGPXLsH21kO04GAjpT9iCYVQ8G1pBAbz4wsItKPaJplR1Mnbzgod797FICBSWNYieOuyYnTw1TAGrA/djbmmfE2MQzJ5TYSjtcQRHxRsYnffkHLbhb6UTPP46xI8OBuZRwzTiEgfo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791893835; c=relaxed/simple; bh=q2k9YKuokvWw9FAPVxMZtwjo2jNOPPsvnM1PEd2HCu4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NY3L5LzlrX0i/o12EGIZXpBAjJTIvrmxtJ22kN70zIvx+80uGGxnGSxH9tLtZhpED8j5DCImNpH1S5nq2xcr4nPbCJi8CR6L40Ydfe7rtoYY0CTjuAHnd9S34E6KSTbND5NpomqHVTxVKe5kw4+JmdbxoQm7dGjj/D3aWCefQZY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=fFxsRliN; 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="fFxsRliN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CBBFD1F000FF; Tue, 13 Oct 2026 12:17:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1791893833; bh=w38LzAFd7EGXx1iLa1qrYPKhbuKCzEM4IGG4lu2Lesc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=fFxsRliNqe3krBHXNNpX3+gWQX1qqWyUWnU3ubDjU8fhzWx4jjydzCqEmO0zp/O3T RL3NjFbEyhTVfpY0mF6Gb6Owq6c7LskdrKkbOlOtcx/WuYBGH5t55ccLKwwt8MyvaJ n3j9gxtjunsPlxa8M6neOwZPt40QZGz0G1sGbNIU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yuho Choi , Vinicius Costa Gomes , Frank Li , Vinod Koul , Sasha Levin Subject: [PATCH 6.18 359/621] dmaengine: idxd: fix double free of wq, engine, and group structs Date: Tue, 13 Oct 2026 13:35:54 +0200 Message-ID: <20261013112929.369599789@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261013112920.855194808@linuxfoundation.org> References: <20261013112920.855194808@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yuho Choi [ Upstream commit ec2d428b2e32dd157de8f86a86dd85c5b2c8f45c ] The release callbacks for wq, engine, and group devices (idxd_conf_wq_release, idxd_conf_engine_release, idxd_conf_group_release) each call kfree() on the enclosing struct. The setup error paths and cleanup functions also call kfree() explicitly after put_device(), producing a double free whenever put_device() drops the reference count to zero and fires the release. In the setup functions, device_initialize() is called before device_add(), so the reference count is exactly 1 at the error sites. put_device() unconditionally fires the release, which frees the struct; the subsequent explicit kfree() then operates on freed memory. For idxd_setup_wqs(), the wq release callback also owns opcap_bmap and wqcfg. The error unwind additionally freed those fields explicitly before calling put_device(), causing further double frees on both. Remove the redundant explicit kfree() calls from all setup error paths and cleanup functions for wq, engine, and group structs, delegating sole ownership of those allocations to the release callbacks. Fixes: 7c5dd23e57c1 ("dmaengine: idxd: fix wq conf_dev 'struct device' lifetime") Fixes: 75b911309060 ("dmaengine: idxd: fix engine conf_dev lifetime") Fixes: defe49f96012 ("dmaengine: idxd: fix group conf_dev lifetime") Signed-off-by: Yuho Choi Acked-by: Vinicius Costa Gomes Reviewed-by: Frank Li Link: https://patch.msgid.link/20260415205452.67155-1-dbgh9129@gmail.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/idxd/init.c | 36 +++++------------------------------- 1 file changed, 5 insertions(+), 31 deletions(-) diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c index afba88f9c3e43..ab4efebb3862c 100644 --- a/drivers/dma/idxd/init.c +++ b/drivers/dma/idxd/init.c @@ -159,18 +159,12 @@ static void idxd_cleanup_interrupts(struct idxd_device *idxd) static void idxd_clean_wqs(struct idxd_device *idxd) { - struct idxd_wq *wq; struct device *conf_dev; int i; for (i = 0; i < idxd->max_wqs; i++) { - wq = idxd->wqs[i]; - if (idxd->hw.wq_cap.op_config) - bitmap_free(wq->opcap_bmap); - kfree(wq->wqcfg); - conf_dev = wq_confdev(wq); + conf_dev = wq_confdev(idxd->wqs[i]); put_device(conf_dev); - kfree(wq); } bitmap_free(idxd->wq_enable_map); kfree(idxd->wqs); @@ -212,7 +206,6 @@ static int idxd_setup_wqs(struct idxd_device *idxd) rc = dev_set_name(conf_dev, "wq%d.%d", idxd->id, wq->id); if (rc < 0) { put_device(conf_dev); - kfree(wq); goto err_unwind; } @@ -226,7 +219,6 @@ static int idxd_setup_wqs(struct idxd_device *idxd) wq->wqcfg = kzalloc_node(idxd->wqcfg_size, GFP_KERNEL, dev_to_node(dev)); if (!wq->wqcfg) { put_device(conf_dev); - kfree(wq); rc = -ENOMEM; goto err_unwind; } @@ -234,9 +226,7 @@ static int idxd_setup_wqs(struct idxd_device *idxd) if (idxd->hw.wq_cap.op_config) { wq->opcap_bmap = bitmap_zalloc(IDXD_MAX_OPCAP_BITS, GFP_KERNEL); if (!wq->opcap_bmap) { - kfree(wq->wqcfg); put_device(conf_dev); - kfree(wq); rc = -ENOMEM; goto err_unwind; } @@ -251,13 +241,8 @@ static int idxd_setup_wqs(struct idxd_device *idxd) err_unwind: while (--i >= 0) { - wq = idxd->wqs[i]; - if (idxd->hw.wq_cap.op_config) - bitmap_free(wq->opcap_bmap); - kfree(wq->wqcfg); - conf_dev = wq_confdev(wq); + conf_dev = wq_confdev(idxd->wqs[i]); put_device(conf_dev); - kfree(wq); } bitmap_free(idxd->wq_enable_map); @@ -269,15 +254,12 @@ static int idxd_setup_wqs(struct idxd_device *idxd) static void idxd_clean_engines(struct idxd_device *idxd) { - struct idxd_engine *engine; struct device *conf_dev; int i; for (i = 0; i < idxd->max_engines; i++) { - engine = idxd->engines[i]; - conf_dev = engine_confdev(engine); + conf_dev = engine_confdev(idxd->engines[i]); put_device(conf_dev); - kfree(engine); } kfree(idxd->engines); } @@ -312,7 +294,6 @@ static int idxd_setup_engines(struct idxd_device *idxd) rc = dev_set_name(conf_dev, "engine%d.%d", idxd->id, engine->id); if (rc < 0) { put_device(conf_dev); - kfree(engine); goto err; } @@ -323,10 +304,8 @@ static int idxd_setup_engines(struct idxd_device *idxd) err: while (--i >= 0) { - engine = idxd->engines[i]; - conf_dev = engine_confdev(engine); + conf_dev = engine_confdev(idxd->engines[i]); put_device(conf_dev); - kfree(engine); } kfree(idxd->engines); @@ -335,13 +314,10 @@ static int idxd_setup_engines(struct idxd_device *idxd) static void idxd_clean_groups(struct idxd_device *idxd) { - struct idxd_group *group; int i; for (i = 0; i < idxd->max_groups; i++) { - group = idxd->groups[i]; - put_device(group_confdev(group)); - kfree(group); + put_device(group_confdev(idxd->groups[i])); } kfree(idxd->groups); } @@ -376,7 +352,6 @@ static int idxd_setup_groups(struct idxd_device *idxd) rc = dev_set_name(conf_dev, "group%d.%d", idxd->id, group->id); if (rc < 0) { put_device(conf_dev); - kfree(group); goto err; } @@ -401,7 +376,6 @@ static int idxd_setup_groups(struct idxd_device *idxd) while (--i >= 0) { group = idxd->groups[i]; put_device(group_confdev(group)); - kfree(group); } kfree(idxd->groups); -- 2.53.0