From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f50.google.com (mail-wr1-f50.google.com [209.85.221.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 07C3F31E83B for ; Mon, 8 Jun 2026 13:48:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.50 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780926501; cv=none; b=E7nspmk2un4LBrp0Cb5+Lcg1kYoIFx9vVbPM6Ia+nv8Q0KfM+kzxERwD6NLHfLBcvnpFB/0NWAAoMwD3s6nW1USpSAzLy3Qgn/KGVw4kU2LMOXSKM9heuTDc4vcPqbrCgJjeR/vz/+4nsR5NQkdjrF3hxds/V/dV+q0elMhCRqQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780926501; c=relaxed/simple; bh=wdMIaMAyWdu4S0DSYGF8WY9qDJK4dJUDqKeDSk483os=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=PNHhslQogcbq8Zh9g7S6qAQ3nqGfrioLxvuiUSDNluc1se+1nuPet+s/LKHAdCotucxollksq/tv7bm5Yk9vl8Ietmji2G4CyasYU1sedUPHnG+1FGvzV+hkZYDvZeq9cT8lKiugti+y7B2RBeyPiX7EFoL0Eeld8gdr9soIh2s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=hackers.camp; spf=pass smtp.mailfrom=gmail.com; arc=none smtp.client-ip=209.85.221.50 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=hackers.camp Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-wr1-f50.google.com with SMTP id ffacd0b85a97d-45ef93a0b0fso255948f8f.2 for ; Mon, 08 Jun 2026 06:48:19 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780926498; x=1781531298; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=DTMnrlV+pTN/lOUFBQDSTc1z3+qQ6zPVzMzDHtmZ+9o=; b=Gn2l9/0EfE37hBNO+Y/qkiLFHg//FC3bzH1rK3HH4/abm0fh0U13IuoMx+WJFVypaj mbLFydiBgh1adv4JIGyRXHLZ9wKL3Xij/ZW3+7XUWPFIoLmqpSV0JWWZz+4M3XoRPOnC lL188PDp+Amvt3nAqAhKkmq3DoDFwpO0AGd71XAbfmSr93cZKfhM3jNUm7bE1+bgdByJ oP64FBjv0Tuk/KQO1atb2p/Fxmgtx0KctK5dIf8N0WogiYyrJEpDDq4AAuLFotDLMcjL 4HcoigJZa0wF/B3eZU9JFJlhh2/DnKg2Ghl18N1RJ0ys3ooFXWlGlXThqSzVkk0I0b0/ fFfA== X-Gm-Message-State: AOJu0Yz8xqtsxZ8xcR1UOI7VLb7QZO8Gb+yr3kIIy0iQLtN6I4t9jGpE YTEv+urBvS5VxOV4TiEnkgMXosLK965OoQs//ALUYXjIWIhr9vYJkR3FbIkIPsRh X-Gm-Gg: Acq92OH4mlGW7NieEumoFNW0i/PLrUR2+KehYdWPbEcWIyFh4B3b94LGUeGYkKlRPT3 H1HFsUyXTy1jlYjjvaDKQluFbazoTPMacjoJxbWgi/Fqdo6AyRvu0N44SfvLao30mRCLo3Mc7zs xD2F+e5bcQUFKFO5LENpz8GiKUYjS9YxbgC97aXIZqXX2VqfTWdVRS9URveZi874gCjvRtP9FpQ FKp4Via9P5ysPmhJen5jcDSJDHTvm+3zw/SGs3t5/KUzD9RI1FCI7hykPoU+zaS2rqlyAfMsSof 8LVtrnzRxRTcAxUkq4wlc/qZXIN+cYZqCSFevCYdnzbwIF8FPuKjFdoAiCd6cb0gTrGE8tY4nR2 C/tAmNVNPBMXr5a452MI5xWpQE2HVIJQ+hFGR3jlrwt5UJldb6xx+y5hZbp3JdNo9mFm3nDii06 BDfyYPY9Yklsy23519Xy0XkW6k9DibR6eaKq/jBsuqNfZ5MFZYixM5uwlfAqvRQbJdwnYVkjYlW A== X-Received: by 2002:a5d:5254:0:b0:450:4980:b4fe with SMTP id ffacd0b85a97d-460302f0b27mr7831225f8f.2.1780926498314; Mon, 08 Jun 2026 06:48:18 -0700 (PDT) Received: from spartian.home ([2a01:cb1c:868:fa00:915c:e3c1:676e:553e]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-4602cda3651sm41027148f8f.32.2026.06.08.06.48.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 08 Jun 2026 06:48:17 -0700 (PDT) From: Aurelien DESBRIERES To: linux-rdma@vger.kernel.org Cc: jgg@ziepe.ca, leon@kernel.org, haris.iqbal@ionos.com, jinpu.wang@ionos.com, gregkh@linuxfoundation.org, Aurelien DESBRIERES Subject: [PATCH] RDMA/rtrs-srv: Fix integer underflow in process_read and process_write Date: Mon, 8 Jun 2026 15:47:15 +0200 Message-ID: <20260608134802.5019-1-aurelien@hackers.camp> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit usr_len is read from a network-supplied message field (le16_to_cpu) and used to compute data_len = off - usr_len without validating that usr_len <= off. A malicious RDMA client can send usr_len > off causing an integer underflow, resulting in data_len wrapping to a huge size_t value which is then passed to the rdma_ev callback as a memory length, leading to out-of-bounds memory access. Fix by reading and validating usr_len <= off before rtrs_srv_get_ops_ids() in both process_read() and process_write(), ensuring the early return path acquires no reference and has no resource leak. Reported-by: Aurelien DESBRIERES Reviewed-by: Md Haris Iqbal Signed-off-by: Aurelien DESBRIERES Assisted-by: Claude --- drivers/infiniband/ulp/rtrs/rtrs-srv.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv.c b/drivers/infiniband/ulp/rtrs/rtrs-srv.c index 6482ad859..f2fd80c8a 100644 --- a/drivers/infiniband/ulp/rtrs/rtrs-srv.c +++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.c @@ -1059,6 +1059,11 @@ static void process_read(struct rtrs_srv_con *con, "Processing read request failed, invalid message\n"); return; } + usr_len = le16_to_cpu(msg->usr_len); + if (usr_len > off) { + pr_debug("rtrs-srv: Invalid usr_len %zu > off %u\n", usr_len, off); + return; + } rtrs_srv_get_ops_ids(srv_path); rtrs_srv_update_rdma_stats(srv_path->stats, off, READ); id = srv_path->ops_ids[buf_id]; @@ -1066,7 +1071,6 @@ static void process_read(struct rtrs_srv_con *con, id->dir = READ; id->msg_id = buf_id; id->rd_msg = msg; - usr_len = le16_to_cpu(msg->usr_len); data_len = off - usr_len; data = page_address(srv->chunks[buf_id]); ret = ctx->ops.rdma_ev(srv->priv, id, data, data_len, @@ -1112,6 +1116,11 @@ static void process_write(struct rtrs_srv_con *con, rtrs_srv_state_str(srv_path->state)); return; } + usr_len = le16_to_cpu(req->usr_len); + if (usr_len > off) { + pr_debug("rtrs-srv: Invalid usr_len %zu > off %u\n", usr_len, off); + return; + } rtrs_srv_get_ops_ids(srv_path); rtrs_srv_update_rdma_stats(srv_path->stats, off, WRITE); id = srv_path->ops_ids[buf_id]; @@ -1119,7 +1128,6 @@ static void process_write(struct rtrs_srv_con *con, id->dir = WRITE; id->msg_id = buf_id; - usr_len = le16_to_cpu(req->usr_len); data_len = off - usr_len; data = page_address(srv->chunks[buf_id]); ret = ctx->ops.rdma_ev(srv->priv, id, data, data_len, -- 2.43.0