From: Colin Ian King colin.king@canonical.com
[ Upstream commit 0788611c9a0925c607de536b2449de5ed98ef8df ]
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 colin.king@canonical.com Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 c4eb55e3011c..c05ef7f1d7b6 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; }