Description
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.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
3b8000ae185cb068adbda5f966a3835053c85fd4 to < e7790ab165713b79b1617ce659742ceb3a859d05affected3b8000ae185cb068adbda5f966a3835053c85fd4 to < 3edb8ebbf79b9016040e8f3421d723ae3d542b32affected3b8000ae185cb068adbda5f966a3835053c85fd4 to < f9719e32a67b4b00b3c9b133e8b5ffa72a26b67baffected3b8000ae185cb068adbda5f966a3835053c85fd4 to < 23b82b7a26182ad840ae67d390d7ec9771e8c00faffected3b8000ae185cb068adbda5f966a3835053c85fd4 to < d757c793853ec5483eb41ec2942c300b8fa720fbaffected3b8000ae185cb068adbda5f966a3835053c85fd4 to < ac1ea219590c09572ed5992dc233bbf7bb70fef9affected
Linux Linux
Default version status: affected
5.18affected0 to < 5.18unaffected6.1.176 to ≤ 6.1.*unaffected6.6.143 to ≤ 6.6.*unaffected6.12.93 to ≤ 6.12.*unaffected6.18.16 to ≤ 6.18.*unaffected6.19.6 to ≤ 6.19.*unaffected7.0 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/e7790ab165713b79b1617ce659742ceb3a859d05 ↗
- https://git.kernel.org/stable/c/3edb8ebbf79b9016040e8f3421d723ae3d542b32 ↗
- https://git.kernel.org/stable/c/f9719e32a67b4b00b3c9b133e8b5ffa72a26b67b ↗
- https://git.kernel.org/stable/c/23b82b7a26182ad840ae67d390d7ec9771e8c00f ↗
- https://git.kernel.org/stable/c/d757c793853ec5483eb41ec2942c300b8fa720fb ↗
- https://git.kernel.org/stable/c/ac1ea219590c09572ed5992dc233bbf7bb70fef9 ↗
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html ↗
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html ↗
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html ↗