Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: dax/fsdev: use __va(phys) for kaddr in direct_access Use __va(phys) instead of virt_addr + linear_offset for the kaddr return in __fsdev_dax_direct_access(). The previous code added a device-linear byte offset to virt_addr (which is __va of ranges[0]), but for multi-range devices with physical gaps between ranges, this linear arithmetic crosses the gap and produces a wrong kernel virtual address. Using __va(phys) where phys comes from dax_pgoff_to_phys() is correct for any range layout because the direct map translates each physical address independently. This leaves dev_dax->virt_addr write-only, so remove the field (suggested by Dave Jiang).
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 759455848df0b9ac3acabdbedcdc4a55af67935f before 7b642bd3d39105eef4d5908970726c5fda291b53; affected 759455848df0b9ac3acabdbedcdc4a55af67935f before ff7c73fca793bd5c29a15ba735b0886f62f3a840 |
| Linux / Linux | affected 7.1; unaffected 0 before 7.1; unaffected 7.2.6 through 7.2.*; unaffected 7.3 through * |
CWE
No CWE identifiers supplied.