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 F1C90326938; Sat, 12 Sep 2026 14:35:02 +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=1789223704; cv=none; b=Cp8nk8et07E5S8XIKi1G0mlsnxuWbjy4vuB8b7XGDyD8tODju2kMTRPcDWx5q78q2TG0ZVVtHZ+IrVXr5nPC+CPG7ieHmFGkZ87/GkP0ELA6b4IFwsqHz4hJdA/4uRH2GMA8jcDpIa/PKFBvtAEnksszA02eT3nHk8ZF4wzY4d0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789223704; c=relaxed/simple; bh=kCjgPG42e+Xr8EcDBrQ+7Dj+YS/Q41XdItD/Lcg905U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XDyQRBzIituM1xWDl/IjQkqB8Jyml45gOa/zKVLosfdTngoeYOqeqKiBfRtRLRtf/Vt8m6XyDGlw1j5I82kHVEq+M4Voeyq59Fjc09aGkFlx3boWw9RcTt1EdF4d1p0+pKGYem5PJO6ZkqHmGM7XZzB8NTWmDq+4HOy4LpVYoNA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=E95ajnjL; 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="E95ajnjL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DA6311F000FF; Sat, 12 Sep 2026 14:35:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789223702; bh=m0SpRLkLbxQRVkG9MT3Lg1qGuovOKIDY/Kog/fRYxw0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=E95ajnjLfhDYHGxcsJFCNx8Rb/o0yFXdiTt7CRd7qNiKOetDueciKj4L+B3q56ylZ uj760R8S7L7HGGV8e5ztiRcAcP5I+BrdEdxNC4ogDBuHpydMx2qT6I1satbirVQL8F rKPqU+9DDkmXCQzAUUxj+1fhf2HnPg2J7/XF63Y0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Patrisious Haddad , Michael Guralnik , Edward Srouji , Leon Romanovsky , Sasha Levin Subject: [PATCH 6.6 0842/1424] RDMA/core: Fix potential use after free in ib_destroy_cq_user() Date: Sat, 12 Sep 2026 08:54:34 +0200 Message-ID: <20260912065626.165565746@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065607.279695368@linuxfoundation.org> References: <20260912065607.279695368@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 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Patrisious Haddad [ Upstream commit 3481bec4dfc4aee24ffea5a547ee95b70b67d9d5 ] When accessing a CQ via the netlink path the only synchronization mechanism for the said CQ is rdma_restrack_get(). Currently, rdma_restrack_del() is invoked at the end of ib_destroy_cq_user(), which is too late, since by that point vendor-specific resources associated with the CQ might already be freed. This can leave a short window where the CQ remains accessible through restrack, leading to a potential use-after-free. Fix this by moving the rdma_restrack_begin_del() call to the start of ib_destroy_cq_user(), ensuring that the CQ is removed from restrack before its internal resources are released. This guarantees that no new users hold references to a CQ that is in the process of destruction. In addition, this change preserves the intended inverted order between create and destroy routines: resources are added to restrack at the end of successful creation, and hence shall be removed from the restrack first thing during the destruction flow, which keeps the lifecycle management consistent and predictable. Fixes: 08f294a1524b ("RDMA/core: Add resource tracking for create and destroy CQs") Signed-off-by: Patrisious Haddad Reviewed-by: Michael Guralnik Signed-off-by: Edward Srouji Link: https://patch.msgid.link/20260713-restrack-uaf-fix-resub-v2-3-bbe8bb270d51@nvidia.com Signed-off-by: Leon Romanovsky Signed-off-by: Sasha Levin --- drivers/infiniband/core/verbs.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c index 90cb7904ba11f..1526ac853218a 100644 --- a/drivers/infiniband/core/verbs.c +++ b/drivers/infiniband/core/verbs.c @@ -2178,11 +2178,15 @@ int ib_destroy_cq_user(struct ib_cq *cq, struct ib_udata *udata) if (atomic_read(&cq->usecnt)) return -EBUSY; + rdma_restrack_begin_del(&cq->res); + ret = cq->device->ops.destroy_cq(cq, udata); - if (ret) + if (ret) { + rdma_restrack_abort_del(&cq->res); return ret; + } - rdma_restrack_del(&cq->res); + rdma_restrack_commit_del(&cq->res); kfree(cq); return ret; } -- 2.53.0