From b627200762c7e8153fe1620fdd52a68f4ca2f8a5 Mon Sep 17 00:00:00 2001 From: Sagi Grimberg Date: Fri, 2 Aug 2019 20:23:38 -0700 Subject: [PATCH] nvmet-tcp: fix possible NULL deref We must only call sgl_free for sgl that we actually allocated. Signed-off-by: Sagi Grimberg --- drivers/nvme/target/tcp.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c index 69b83fa0c76c..0d63f3da0117 100644 --- a/drivers/nvme/target/tcp.c +++ b/drivers/nvme/target/tcp.c @@ -348,7 +348,8 @@ static int nvmet_tcp_map_data(struct nvmet_tcp_cmd *cmd) return 0; err: - sgl_free(cmd->req.sg); + if (cmd->req.sg_cnt) + sgl_free(cmd->req.sg); return NVME_SC_INTERNAL; } @@ -553,7 +554,8 @@ static int nvmet_try_send_data(struct nvmet_tcp_cmd *cmd) if (queue->nvme_sq.sqhd_disabled) { kfree(cmd->iov); - sgl_free(cmd->req.sg); + if (cmd->req.sg_cnt) + sgl_free(cmd->req.sg); } return 1; @@ -584,7 +586,8 @@ static int nvmet_try_send_response(struct nvmet_tcp_cmd *cmd, return -EAGAIN; kfree(cmd->iov); - sgl_free(cmd->req.sg); + if (cmd->req.sg_cnt) + sgl_free(cmd->req.sg); cmd->queue->snd_cmd = NULL; nvmet_tcp_put_cmd(cmd); return 1; @@ -1306,7 +1309,8 @@ static void nvmet_tcp_finish_cmd(struct nvmet_tcp_cmd *cmd) { nvmet_req_uninit(&cmd->req); nvmet_tcp_unmap_pdu_iovec(cmd); - sgl_free(cmd->req.sg); + if (cmd->req.sg_cnt) + sgl_free(cmd->req.sg); } static void nvmet_tcp_uninit_data_in_cmds(struct nvmet_tcp_queue *queue)