CVE-2021-47047

In the Linux kernel, the following vulnerability has been resolved:

spi: spi-zynqmp-gqspi: return -ENOMEM if dma_map_single fails

The spi controller supports 44-bit address space on AXI in DMA mode, so set dma_addr_t width to 44-bit to avoid using a swiotlb mapping. In addition, if dma_map_single fails, it should return immediately instead of continuing doing the DMA operation which bases on invalid address.

This fixes the following crash which occurs in reading a big block from flash:

[ 123.633577] zynqmp-qspi ff0f0000.spi: swiotlb buffer is full (sz: 4194304 bytes), total 32768 (slots), used 0 (slots) [ 123.644230] zynqmp-qspi ff0f0000.spi: ERR:rxdma:memory not mapped [ 123.784625] Unable to handle kernel paging request at virtual address 00000000003fffc0 [ 123.792536] Mem abort info: [ 123.795313] ESR = 0x96000145 [ 123.798351] EC = 0x25: DABT (current EL), IL = 32 bits [ 123.803655] SET = 0, FnV = 0 [ 123.806693] EA = 0, S1PTW = 0 [ 123.809818] Data abort info: [ 123.812683] ISV = 0, ISS = 0x00000145 [ 123.816503] CM = 1, WnR = 1 [ 123.819455] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000805047000 [ 123.825887] [00000000003fffc0] pgd=0000000803b45003, p4d=0000000803b45003, pud=0000000000000000 [ 123.834586] Internal error: Oops: 96000145 [#1] PREEMPT SMP