mm/page_alloc: clear page->private in free_pages_prepare()
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 6.1.176, 6.6.143, 6.12.93, 6.18.16, 6.19.6
- 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
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
In the Linux kernel, the following vulnerability has been resolved: mm/page_alloc: clear page->private in free_pages_prepare() Several subsystems (slub, shmem, ttm, etc.) use page->private but don't clear it before freeing pages. When these pages are later allocated as high-order pages and split via split_page(), tail pages retain stale page->private values. This causes a use-after-free in the swap subsystem. The swap code uses page->private to track swap count continuations, assuming freshly allocated pages have page->private == 0. When stale values are present, swap_count_continued() incorrectly assumes the continuation list is valid and iterates over uninitialized page->lru containing LIST_POISON values, causing a crash: KASAN: maybe wild-memory-access in range [0xdead000000000100-0xdead000000000107] RIP: 0010:__do_sys_swapoff+0x1151/0x1860 Fix this by clearing page->private in free_pages_prepare(), ensuring all freed pages have clean state regardless of previous use.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- Linux Linux
From 3b8000ae185cb068adbda5f966a3835053c85fd4 · fixed in e7790ab165713b79b1617ce659742ceb3a859d05; From 3b8000ae185cb068adbda5f966a3835053c85fd4 · fixed in 3edb8ebbf79b9016040e8f3421d723ae3d542b32; From 3b8000ae185cb068adbda5f966a3835053c85fd4 · fixed in f9719e32a67b4b00b3c9b133e8b5ffa72a26b67b; From 3b8000ae185cb068adbda5f966a3835053c85fd4 · fixed in 23b82b7a26182ad840ae67d390d7ec9771e8c00f; From 3b8000ae185cb068adbda5f966a3835053c85fd4 · fixed in d757c793853ec5483eb41ec2942c300b8fa720fb; From 3b8000ae185cb068adbda5f966a3835053c85fd4 · fixed in ac1ea219590c09572ed5992dc233bbf7bb70fef9
- Linux Linux
5.18
- KernelLinux
From 5.18.0 · fixed in 6.1.176; From 6.2.0 · fixed in 6.6.143; From 6.7.0 · fixed in 6.12.93; From 6.13.0 · fixed in 6.18.16; From 6.19.0 · fixed in 6.19.6