From: Jiasheng Jiang <jiasheng@xxxxxxxxxxx> [ Upstream commit b3d40c3ec3dc4ad78017de6c3a38979f57aaaab8 ] As the kcalloc may return NULL pointer, it should be better to check the ishtp_dma_tx_map before use in order to avoid NULL pointer dereference. Fixes: 3703f53b99e4 ("HID: intel_ish-hid: ISH Transport layer") Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx> Acked-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx> Signed-off-by: Jiri Kosina <jkosina@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/hid/intel-ish-hid/ishtp/dma-if.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/hid/intel-ish-hid/ishtp/dma-if.c b/drivers/hid/intel-ish-hid/ishtp/dma-if.c index 2783f3666114..ff4419c8ed4f 100644 --- a/drivers/hid/intel-ish-hid/ishtp/dma-if.c +++ b/drivers/hid/intel-ish-hid/ishtp/dma-if.c @@ -113,6 +113,11 @@ void *ishtp_cl_get_dma_send_buf(struct ishtp_device *dev, int required_slots = (size / DMA_SLOT_SIZE) + 1 * (size % DMA_SLOT_SIZE != 0); + if (!dev->ishtp_dma_tx_map) { + dev_err(dev->devc, "Fail to allocate Tx map\n"); + return NULL; + } + spin_lock_irqsave(&dev->ishtp_dma_tx_lock, flags); for (i = 0; i <= (dev->ishtp_dma_num_slots - required_slots); i++) { free = 1; @@ -159,6 +164,11 @@ void ishtp_cl_release_dma_acked_mem(struct ishtp_device *dev, return; } + if (!dev->ishtp_dma_tx_map) { + dev_err(dev->devc, "Fail to allocate Tx map\n"); + return; + } + i = (msg_addr - dev->ishtp_host_dma_tx_buf) / DMA_SLOT_SIZE; spin_lock_irqsave(&dev->ishtp_dma_tx_lock, flags); for (j = 0; j < acked_slots; j++) { -- 2.39.0