CVE-2025-38451: md/md-bitmap: fix GPF in bitmap_get_stats()

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-07-25 · updated 2026-06-17

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.

Affected products

Debian Linux: 11.0
Linux kernel: from 6.1.135 before 6.1.146; from 6.6.88 before 6.6.99; from 6.12.25 before 6.12.39; from 6.14.4 before 6.15; from 6.15.1 before 6.15.7; 6.15, 6.15-rc3, 6.15-rc4, 6.15-rc5, 6.15-rc6, 6.15-rc7 (+5) — fixed in 6.1.146, 6.12.39, 6.15, 6.15.7, 6.6.99

How to fix

Upgrade to a fixed version: Linux kernel 6.1.146, 6.12.39, 6.15, 6.15.7. Check the vendor advisory for mitigations.

References

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