From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41836) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gadwN-0006Zg-N8 for qemu-devel@nongnu.org; Sat, 22 Dec 2018 04:51:28 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gadwM-0006kq-Qb for qemu-devel@nongnu.org; Sat, 22 Dec 2018 04:51:27 -0500 Received: from mail-wr1-x441.google.com ([2a00:1450:4864:20::441]:35006) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1gadwM-0006do-KE for qemu-devel@nongnu.org; Sat, 22 Dec 2018 04:51:26 -0500 Received: by mail-wr1-x441.google.com with SMTP id 96so7530874wrb.2 for ; Sat, 22 Dec 2018 01:51:17 -0800 (PST) From: Marcel Apfelbaum Date: Sat, 22 Dec 2018 11:50:31 +0200 Message-Id: <20181222095036.29743-27-marcel.apfelbaum@gmail.com> In-Reply-To: <20181222095036.29743-1-marcel.apfelbaum@gmail.com> References: <20181222095036.29743-1-marcel.apfelbaum@gmail.com> Subject: [Qemu-devel] [PATCH PULL 26/31] rdma: check num_sge does not exceed MAX_SGE List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, peter.maydell@linaro.org Cc: yuval.shaia@oracle.com, marcel.apfelbaum@gmail.com, pjp@fedoraproject.org From: Prasad J Pandit rdma back-end has scatter/gather array ibv_sge[MAX_SGE=4] set to have 4 elements. A guest could send a 'PvrdmaSqWqe' ring element with 'num_sge' set to > MAX_SGE, which may lead to OOB access issue. Add check to avoid it. Reported-by: Saar Amar Signed-off-by: Prasad J Pandit Reviewed-by: Yuval Shaia Signed-off-by: Marcel Apfelbaum --- hw/rdma/rdma_backend.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/hw/rdma/rdma_backend.c b/hw/rdma/rdma_backend.c index ae1e4dcb29..bd4710d16f 100644 --- a/hw/rdma/rdma_backend.c +++ b/hw/rdma/rdma_backend.c @@ -476,9 +476,9 @@ void rdma_backend_post_send(RdmaBackendDev *backend_dev, } pr_dbg("num_sge=%d\n", num_sge); - if (!num_sge) { - pr_dbg("num_sge=0\n"); - complete_work(IBV_WC_GENERAL_ERR, VENDOR_ERR_NO_SGE, ctx); + if (!num_sge || num_sge > MAX_SGE) { + pr_dbg("invalid num_sge=%d\n", num_sge); + complete_work(IBV_WC_GENERAL_ERR, VENDOR_ERR_INV_NUM_SGE, ctx); return; } @@ -603,9 +603,9 @@ void rdma_backend_post_recv(RdmaBackendDev *backend_dev, } pr_dbg("num_sge=%d\n", num_sge); - if (!num_sge) { - pr_dbg("num_sge=0\n"); - complete_work(IBV_WC_GENERAL_ERR, VENDOR_ERR_NO_SGE, ctx); + if (!num_sge || num_sge > MAX_SGE) { + pr_dbg("invalid num_sge=%d\n", num_sge); + complete_work(IBV_WC_GENERAL_ERR, VENDOR_ERR_INV_NUM_SGE, ctx); return; } -- 2.17.1