CVE-2023-52979

In the Linux kernel, the following vulnerability has been resolved:

squashfs: harden sanity check in squashfs_read_xattr_id_table

While mounting a corrupted filesystem, a signed integer *xattr_ids can become less than zero. This leads to the incorrect computation of len and indexes values which can cause null-ptr-deref in copy_bio_to_actor() or out-of-bounds accesses in the next sanity checks inside squashfs_read_xattr_id_table().

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Weakness

A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit.

Affected Software

Potential Mitigations

References

• https://git.kernel.org/stable/c/29e774dcb27116c06b9c57b1f1f14a1623738989
• https://git.kernel.org/stable/c/72e544b1b28325fe78a4687b980871a7e4101f76
• https://git.kernel.org/stable/c/b30a74f83265c24d1d0842c6c3928cd2e775a3fb
• https://git.kernel.org/stable/c/b7398efe24a965cf3937b716c0b1011c201c5d6e
• https://git.kernel.org/stable/c/cf5d6612092408157db6bb500c70bf6d67c40fbc
• https://git.kernel.org/stable/c/db76fc535fbdfbf29fd0b93e49627537ad794c8c
• https://git.kernel.org/stable/c/de2785aa3448d1ee7be3ab47fd4a873025f1b3d7