CVE-2024-46852: debian debian_linux Off-by-one Error

Vulnerability summary

CVE-2024-46852 is a high (CVSS 7.8) Off-by-one Error vulnerability in debian debian_linux. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 11.2% of scored vulnerabilities.

Timeline

1. 27-09-2024
   PublishedVulnerability first disclosed.
2. 05-08-2026
   Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: dma-buf: heaps: Fix off-by-one in CMA heap fault handler Until VM_DONTEXPAND was added in commit 1c1914d6e8c6 ("dma-buf: heaps: Don't track CMA dma-buf pages under RssFile") it was possible to obtain a mapping larger than the buffer size via mremap and bypass the overflow check in dma_buf_mmap_internal. When using such a mapping to attempt to fault past the end of the buffer, the CMA heap fault handler also checks the fault offset against the buffer size, but gets the boundary wrong by 1. Fix the boundary check so that we don't read off the end of the pages array and insert an arbitrary page in the mapping.

• CWE-193Off-by-one ErrorA product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value.