diff --git a/drivers/rpmsg/qcom_glink_smem.c b/drivers/rpmsg/qcom_glink_smem.c index 47c098bfe6de..512656632505 100644 --- a/drivers/rpmsg/qcom_glink_smem.c +++ b/drivers/rpmsg/qcom_glink_smem.c @@ -1,7 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 /* * Copyright (c) 2016, Linaro Ltd - * Copyright (c) 2018, The Linux Foundation, All rights reserved. + * Copyright (c) 2018-2019, The Linux Foundation, All rights reserved. */ #include <linux/io.h> @@ -72,9 +72,14 @@ static size_t glink_smem_rx_avail(struct qcom_glink_pipe *np) tail = le32_to_cpu(*pipe->tail); if (head < tail) - return pipe->native.length - tail + head; + len = pipe->native.length - tail + head; else - return head - tail; + len = head - tail; + + if (WARN_ON_ONCE(len > pipe->native.length)) + len = 0; + + return len; } static void glink_smem_rx_peak(struct qcom_glink_pipe *np, @@ -85,6 +90,10 @@ static void glink_smem_rx_peak(struct qcom_glink_pipe *np, u32 tail; tail = le32_to_cpu(*pipe->tail); + + if (WARN_ON_ONCE(tail > pipe->native.length)) + return; + tail += offset; if (tail >= pipe->native.length) tail -= pipe->native.length; @@ -109,7 +118,7 @@ static void glink_smem_rx_advance(struct qcom_glink_pipe *np, tail += count; if (tail >= pipe->native.length) - tail -= pipe->native.length; + tail %= pipe->native.length; *pipe->tail = cpu_to_le32(tail); } @@ -134,6 +143,9 @@ static size_t glink_smem_tx_avail(struct qcom_glink_pipe *np) else avail -= FIFO_FULL_RESERVE + TX_BLOCKED_CMD_RESERVE; + if (WARN_ON_ONCE(avail > pipe->native.length)) + avail = 0; + return avail; } @@ -143,6 +155,9 @@ static unsigned int glink_smem_tx_write_one(struct glink_smem_pipe *pipe, { size_t len; + if (WARN_ON_ONCE(head > pipe->native.length)) + return head; + len = min_t(size_t, count, pipe->native.length - head); if (len) memcpy(pipe->fifo + head, data, len);