From 0788611c9a0925c607de536b2449de5ed98ef8df Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Wed, 8 May 2019 23:33:29 +0100 Subject: dmaengine: dw-axi-dmac: fix null dereference when pointer first is null In the unlikely event that axi_desc_get returns a null desc in the very first iteration of the while-loop the error exit path ends up calling axi_desc_put on a null pointer 'first' and this causes a null pointer dereference. Fix this by adding a null check on pointer 'first' before calling axi_desc_put. Addresses-Coverity: ("Explicit null dereference") Fixes: 1fe20f1b8454 ("dmaengine: Introduce DW AXI DMAC driver") Signed-off-by: Colin Ian King Signed-off-by: Vinod Koul --- drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c index b2ac1d2c5b86..a1ce307c502f 100644 --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c @@ -512,7 +512,8 @@ dma_chan_prep_dma_memcpy(struct dma_chan *dchan, dma_addr_t dst_adr, return vchan_tx_prep(&chan->vc, &first->vd, flags); err_desc_get: - axi_desc_put(first); + if (first) + axi_desc_put(first); return NULL; } -- cgit v1.2.3