CVE-2025-38451

/// Technical description

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

md/md-bitmap: fix GPF in bitmap_get_stats()

The commit message of commit 6ec1f0239485 ("md/md-bitmap: fix stats

collection for external bitmaps") states:

Remove the external bitmap check as the statistics should be

available regardless of bitmap storage location.

Return -EINVAL only for invalid bitmap with no storage (neither in

superblock nor in external file).

But, the code does not adhere to the above, as it does only check for

a valid super-block for "internal" bitmaps. Hence, we observe:

Oops: GPF, probably for non-canonical address 0x1cd66f1f40000028

RIP: 0010:bitmap_get_stats+0x45/0xd0

Call Trace:

seq_read_iter+0x2b9/0x46a

seq_read+0x12f/0x180

proc_reg_read+0x57/0xb0

vfs_read+0xf6/0x380

ksys_read+0x6d/0xf0

do_syscall_64+0x8c/0x1b0

entry_SYSCALL_64_after_hwframe+0x76/0x7e

We fix this by checking the existence of a super-block for both the

internal and external case.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References