imPC@ndo IT

Tracker / CVE-2022-49080

CVE-2022-49080

Medium 5.5

In the Linux kernel, the following vulnerability has been resolved: mm/mempolicy: fix mpol_new leak in shared_policy_replace If mpol_new is allocated but not used in restart loop, mpol_new will be freed via mpol_put before returning to the caller. But refcnt is not initialized yet, so mpol_put could not do the right things and might leak the unused mpol_new. This would happen if mempolicy was updated on the shared shmem file while the sp->lock has been dropped during the memory allocation. This issue could be triggered easily with the below code snippet if there are many processes doing the below work at the same time: shmid = shmget((key_t)5566, 1024 * PAGE_SIZE, 0666|IPC_CREAT); shm = shmat(shmid, 0, 0); loop many times { mbind(shm, 1024 * PAGE_SIZE, MPOL_LOCAL, mask, maxnode, 0); mbind(shm + 128 * PAGE_SIZE, 128 * PAGE_SIZE, MPOL_DEFAULT, mask, maxnode, 0); }

Affected products and versions

linux linux_kernel
linux linux_kernel · 3.8.1 → 4.9.311
linux linux_kernel · 4.10 → 4.14.276
linux linux_kernel · 4.15 → 4.19.238
linux linux_kernel · 4.20 → 5.4.189
linux linux_kernel · 5.11 → 5.15.34
linux linux_kernel · 5.16 → 5.16.20
linux linux_kernel · 5.17 → 5.17.3
linux linux_kernel · 5.5 → 5.10.111

Analysis

This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.

References