md: scope memalloc_noio to allocation critical sections
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 6.12.110, 6.18.52, 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: md: scope memalloc_noio to allocation critical sections Storing a memalloc_noio_save() token in mddev->noio_flags lets one task save the token and another task restore it. With concurrent suspend sysfs writes, task A can enter PF_MEMALLOC_NOIO, return to userspace still in that scope, and later task B can restore A's saved token. Avoid tying the token lifetime to mddev. Keep mddev_suspend() and mddev_resume() only responsible for array suspension, and enter PF_MEMALLOC_NOIO only in the MD paths that allocate memory after the array has been suspended. Restore the token before resuming the array. A reproducer repeatedly writes suspend_lo and suspend_hi from concurrent workers and checks each worker's /proc/self/stat flags before and after the sysfs write.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 78f57ef9d50a75326da73d352d7c27828495229a · fixed in 72ebfdf507ede7d7f2b7ca0a5634811a0e4bf045; From 78f57ef9d50a75326da73d352d7c27828495229a · fixed in 28fdea874f68cac6c36651b1fc7272fd2199c48d; From 78f57ef9d50a75326da73d352d7c27828495229a · fixed in a58923756b0f8e71032070c23ae0b167e46731da; From 78f57ef9d50a75326da73d352d7c27828495229a · fixed in bace2010dd7ac07bc980575afb135c406730a7fe
- Linux Linux
5.8
- KernelLinux
From 5.8.0 · fixed in 6.12.110; From 6.13.0 · fixed in 6.18.52; From 6.19.0 · fixed in 7.2.6