From: Dan Carpenter dan.carpenter@oracle.com
commit 595a334148449bd1d27cf5d6fcb3b0d718cb1b9f upstream.
If the dw_edma_alloc_burst() function fails then we free "chunk" but it's still on the "desc->chunk->list" list so it will lead to a use after free. Also the "->chunks_alloc" count is incremented when it shouldn't be.
In current kernels small allocations are guaranteed to succeed and dw_edma_alloc_burst() can't fail so this will not actually affect runtime.
Fixes: e63d79d1ffcd ("dmaengine: Add Synopsys eDMA IP core driver") Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Acked-by: Gustavo Pimentel gustavo.pimentel@synopsys.com Link: https://lore.kernel.org/r/X9dTBFrUPEvvW7qc@mwanda Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/dma/dw-edma/dw-edma-core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/dma/dw-edma/dw-edma-core.c +++ b/drivers/dma/dw-edma/dw-edma-core.c @@ -86,12 +86,12 @@ static struct dw_edma_chunk *dw_edma_all
if (desc->chunk) { /* Create and add new element into the linked list */ - desc->chunks_alloc++; - list_add_tail(&chunk->list, &desc->chunk->list); if (!dw_edma_alloc_burst(chunk)) { kfree(chunk); return NULL; } + desc->chunks_alloc++; + list_add_tail(&chunk->list, &desc->chunk->list); } else { /* List head */ chunk->burst = NULL;