5.4-stable review patch. If anyone has any objections, please let me know.
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From: Chen Ridong chenridong@huawei.com
commit c43ec96e8d34399bd9dab2f2dc316b904892133f upstream.
The at_xdmac_memset_create_desc may return NULL, which will lead to a null pointer dereference. For example, the len input is error, or the atchan->free_descs_list is empty and memory is exhausted. Therefore, add check to avoid this.
Fixes: b206d9a23ac7 ("dmaengine: xdmac: Add memset support") Signed-off-by: Chen Ridong chenridong@huawei.com Link: https://lore.kernel.org/r/20241029082845.1185380-1-chenridong@huaweicloud.co... Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/dma/at_xdmac.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -1214,6 +1214,8 @@ at_xdmac_prep_dma_memset(struct dma_chan return NULL;
desc = at_xdmac_memset_create_desc(chan, atchan, dest, len, value); + if (!desc) + return NULL; list_add_tail(&desc->desc_node, &desc->descs_list);
desc->tx_dma_desc.cookie = -EBUSY;