CVE-2021-47047: linux kernel vulnerability
CVE-2021-47047: medium vulnerability affecting linux kernel. Check CVSS, KEV status, business impact and recommended administrator actions.
- CVSS
- 5.5 MEDIUM
- EPSS
- 15.1%
- Known exploited
- not in KEV
- Product
- linux kernel
What is known
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
Business impact
Successful exploitation of CVE-2021-47047, a medium vulnerability (CVSS 5.5) affecting linux kernel, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.
Recommended administrator action
Confirm whether linux kernel is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.