CVE-2025-38072

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> libnvdimm/labels: Fix divide error in nd_label_data_init()<br /> <br /> If a faulty CXL memory device returns a broken zero LSA size in its<br /> memory device information (Identify Memory Device (Opcode 4000h), CXL<br /> spec. 3.1, 8.2.9.9.1.1), a divide error occurs in the libnvdimm<br /> driver:<br /> <br /> Oops: divide error: 0000 [#1] PREEMPT SMP NOPTI<br /> RIP: 0010:nd_label_data_init+0x10e/0x800 [libnvdimm]<br /> <br /> Code and flow:<br /> <br /> 1) CXL Command 4000h returns LSA size = 0<br /> 2) config_size is assigned to zero LSA size (CXL pmem driver):<br /> <br /> drivers/cxl/pmem.c: .config_size = mds-&gt;lsa_size,<br /> <br /> 3) max_xfer is set to zero (nvdimm driver):<br /> <br /> drivers/nvdimm/label.c: max_xfer = min_t(size_t, ndd-&gt;nsarea.max_xfer, config_size);<br /> <br /> 4) A subsequent DIV_ROUND_UP() causes a division by zero:<br /> <br /> drivers/nvdimm/label.c: /* Make our initial read size a multiple of max_xfer size */<br /> drivers/nvdimm/label.c: read_size = min(DIV_ROUND_UP(read_size, max_xfer) * max_xfer,<br /> drivers/nvdimm/label.c- config_size);<br /> <br /> Fix this by checking the config size parameter by extending an<br /> existing check.