4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Thomas Petazzoni <[email protected]> commit eb8df543e444492328f506adffc7dfe94111f1bd upstream. The mv_xor_v2_prep_sw_desc() is called from a few different places in the driver, but we never take into account the fact that it might return NULL. This commit fixes that, ensuring that we don't panic if there are no more descriptors available. Fixes: 19a340b1a820 ("dmaengine: mv_xor_v2: new driver") Signed-off-by: Thomas Petazzoni <[email protected]> Signed-off-by: Vinod Koul <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/dma/mv_xor_v2.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/dma/mv_xor_v2.c +++ b/drivers/dma/mv_xor_v2.c @@ -389,6 +389,8 @@ mv_xor_v2_prep_dma_memcpy(struct dma_cha __func__, len, &src, &dest, flags); sw_desc = mv_xor_v2_prep_sw_desc(xor_dev); + if (!sw_desc) + return NULL; sw_desc->async_tx.flags = flags; @@ -443,6 +445,8 @@ mv_xor_v2_prep_dma_xor(struct dma_chan * __func__, src_cnt, len, &dest, flags); sw_desc = mv_xor_v2_prep_sw_desc(xor_dev); + if (!sw_desc) + return NULL; sw_desc->async_tx.flags = flags; @@ -491,6 +495,8 @@ mv_xor_v2_prep_dma_interrupt(struct dma_ container_of(chan, struct mv_xor_v2_device, dmachan); sw_desc = mv_xor_v2_prep_sw_desc(xor_dev); + if (!sw_desc) + return NULL; /* set the HW descriptor */ hw_descriptor = &sw_desc->hw_desc;
