dax/fsdev: use __va(phys) for kaddr in direct_access
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 7.2.6
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
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).
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 759455848df0b9ac3acabdbedcdc4a55af67935f · fixed in 7b642bd3d39105eef4d5908970726c5fda291b53; From 759455848df0b9ac3acabdbedcdc4a55af67935f · fixed in ff7c73fca793bd5c29a15ba735b0886f62f3a840
- Linux Linux
7.1
- KernelLinux
From 7.1.0 · fixed in 7.2.6