From: Maurizio Lombardi Date: Mon, 16 Mar 2026 14:39:35 +0000 (+0100) Subject: nvmet-tcp: propagate nvmet_tcp_build_pdu_iovec() errors to its callers X-Git-Tag: v7.1-rc2~13^2~2^2~17 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ea8e356acb165cb1fd75537a52e1f66e5e76c538;p=thirdparty%2Fkernel%2Flinux.git nvmet-tcp: propagate nvmet_tcp_build_pdu_iovec() errors to its callers Currently, when nvmet_tcp_build_pdu_iovec() detects an out-of-bounds PDU length or offset, it triggers nvmet_tcp_fatal_error(cmd->queue) and returns early. However, because the function returns void, the callers are entirely unaware that a fatal error has occurred and that the cmd->recv_msg.msg_iter was left uninitialized. Callers such as nvmet_tcp_handle_h2c_data_pdu() proceed to blindly overwrite the queue state with queue->rcv_state = NVMET_TCP_RECV_DATA Consequently, the socket receiving loop may attempt to read incoming network data into the uninitialized iterator. Fix this by shifting the error handling responsibility to the callers. Fixes: 52a0a9854934 ("nvmet-tcp: add bounds checks in nvmet_tcp_build_pdu_iovec") Reviewed-by: Hannes Reinecke Reviewed-by: Yunje Shin Reviewed-by: Chaitanya Kulkarni Signed-off-by: Maurizio Lombardi Signed-off-by: Keith Busch --- diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c index 69e971b179ae..3ade734c8bcf 100644 --- a/drivers/nvme/target/tcp.c +++ b/drivers/nvme/target/tcp.c @@ -351,7 +351,7 @@ static void nvmet_tcp_free_cmd_buffers(struct nvmet_tcp_cmd *cmd) static void nvmet_tcp_fatal_error(struct nvmet_tcp_queue *queue); -static void nvmet_tcp_build_pdu_iovec(struct nvmet_tcp_cmd *cmd) +static int nvmet_tcp_build_pdu_iovec(struct nvmet_tcp_cmd *cmd) { struct bio_vec *iov = cmd->iov; struct scatterlist *sg; @@ -364,22 +364,19 @@ static void nvmet_tcp_build_pdu_iovec(struct nvmet_tcp_cmd *cmd) offset = cmd->rbytes_done; cmd->sg_idx = offset / PAGE_SIZE; sg_offset = offset % PAGE_SIZE; - if (!cmd->req.sg_cnt || cmd->sg_idx >= cmd->req.sg_cnt) { - nvmet_tcp_fatal_error(cmd->queue); - return; - } + if (!cmd->req.sg_cnt || cmd->sg_idx >= cmd->req.sg_cnt) + return -EPROTO; + sg = &cmd->req.sg[cmd->sg_idx]; sg_remaining = cmd->req.sg_cnt - cmd->sg_idx; while (length) { - if (!sg_remaining) { - nvmet_tcp_fatal_error(cmd->queue); - return; - } - if (!sg->length || sg->length <= sg_offset) { - nvmet_tcp_fatal_error(cmd->queue); - return; - } + if (!sg_remaining) + return -EPROTO; + + if (!sg->length || sg->length <= sg_offset) + return -EPROTO; + u32 iov_len = min_t(u32, length, sg->length - sg_offset); bvec_set_page(iov, sg_page(sg), iov_len, @@ -394,6 +391,7 @@ static void nvmet_tcp_build_pdu_iovec(struct nvmet_tcp_cmd *cmd) iov_iter_bvec(&cmd->recv_msg.msg_iter, ITER_DEST, cmd->iov, nr_pages, cmd->pdu_len); + return 0; } static void nvmet_tcp_fatal_error(struct nvmet_tcp_queue *queue) @@ -931,7 +929,7 @@ static int nvmet_tcp_handle_icreq(struct nvmet_tcp_queue *queue) return 0; } -static void nvmet_tcp_handle_req_failure(struct nvmet_tcp_queue *queue, +static int nvmet_tcp_handle_req_failure(struct nvmet_tcp_queue *queue, struct nvmet_tcp_cmd *cmd, struct nvmet_req *req) { size_t data_len = le32_to_cpu(req->cmd->common.dptr.sgl.length); @@ -947,19 +945,23 @@ static void nvmet_tcp_handle_req_failure(struct nvmet_tcp_queue *queue, if (!nvme_is_write(cmd->req.cmd) || !data_len || data_len > cmd->req.port->inline_data_size) { nvmet_prepare_receive_pdu(queue); - return; + return 0; } ret = nvmet_tcp_map_data(cmd); if (unlikely(ret)) { pr_err("queue %d: failed to map data\n", queue->idx); nvmet_tcp_fatal_error(queue); - return; + return -EPROTO; } queue->rcv_state = NVMET_TCP_RECV_DATA; - nvmet_tcp_build_pdu_iovec(cmd); cmd->flags |= NVMET_TCP_F_INIT_FAILED; + ret = nvmet_tcp_build_pdu_iovec(cmd); + if (unlikely(ret)) + pr_err("queue %d: failed to build PDU iovec\n", queue->idx); + + return ret; } static int nvmet_tcp_handle_h2c_data_pdu(struct nvmet_tcp_queue *queue) @@ -1011,7 +1013,10 @@ static int nvmet_tcp_handle_h2c_data_pdu(struct nvmet_tcp_queue *queue) goto err_proto; } cmd->pdu_recv = 0; - nvmet_tcp_build_pdu_iovec(cmd); + if (unlikely(nvmet_tcp_build_pdu_iovec(cmd))) { + pr_err("queue %d: failed to build PDU iovec\n", queue->idx); + goto err_proto; + } queue->cmd = cmd; queue->rcv_state = NVMET_TCP_RECV_DATA; @@ -1074,8 +1079,7 @@ static int nvmet_tcp_done_recv_pdu(struct nvmet_tcp_queue *queue) le32_to_cpu(req->cmd->common.dptr.sgl.length), le16_to_cpu(req->cqe->status)); - nvmet_tcp_handle_req_failure(queue, queue->cmd, req); - return 0; + return nvmet_tcp_handle_req_failure(queue, queue->cmd, req); } ret = nvmet_tcp_map_data(queue->cmd); @@ -1092,8 +1096,11 @@ static int nvmet_tcp_done_recv_pdu(struct nvmet_tcp_queue *queue) if (nvmet_tcp_need_data_in(queue->cmd)) { if (nvmet_tcp_has_inline_data(queue->cmd)) { queue->rcv_state = NVMET_TCP_RECV_DATA; - nvmet_tcp_build_pdu_iovec(queue->cmd); - return 0; + ret = nvmet_tcp_build_pdu_iovec(queue->cmd); + if (unlikely(ret)) + pr_err("queue %d: failed to build PDU iovec\n", + queue->idx); + return ret; } /* send back R2T */ nvmet_tcp_queue_response(&queue->cmd->req);