High · published December 24, 2025
In the Linux kernel, the following vulnerability has been resolved:
erofs: validate the extent length for uncompressed pclusters
syzkaller reported a KASAN use-after-free:
https://syzkaller.appspot.com/bug?extid=2ae90e873e97f1faf6f2
The referenced fuzzed image actually has two issues:
- m_pa == 0 as a non-inlined pcluster;
- The logical length is longer than its physical length.
The first issue has already been addressed. This patch addresses
the second issue by checking the extent length validity.