CVE-2026-64417
CVE.org · Published
- Record status
- Published
- Identifier year (not publication year)
- 2026
- Source publication
- Source updated
- Imported by cveboard
- Source snapshot
- cve_2026-10-24_midnight_baseline ·
CNA source text (English)
mm: shrinker: fix NULL pointer dereference in debugfs
In the Linux kernel, the following vulnerability has been resolved: mm: shrinker: fix NULL pointer dereference in debugfs shrinker_debugfs_add() creates both "count" and "scan" debugfs files unconditionally. That assumes every shrinker implements both count_objects() and scan_objects(), which is not guaranteed. For example, the xen-backend shrinker sets count_objects() but leaves scan_objects() NULL, so writing to its scan file calls through a NULL function pointer and panics the kernel: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. Call Trace: <TASK> shrinker_debugfs_scan_write+0x12e/0x270 full_proxy_write+0x5f/0x90 vfs_write+0xde/0x420 ? filp_flush+0x75/0x90 ? filp_close+0x1d/0x30 ? do_dup2+0xb8/0x120 ksys_write+0x68/0xf0 ? filp_flush+0x75/0x90 do_syscall_64+0xb3/0x5b0 entry_SYSCALL_64_after_hwframe+0x76/0x7e The count path has the same issue in principle if a shrinker omits count_objects(). To fix it, only create "count" and "scan" debugfs files when the corresponding callbacks are present.
Scoped product and version facts
Fix information unknown; no fixed version is derived here. Missing information does not prove that no fix exists.
Exploitation unknown; this catalogue does not assess exploitation.
Linux
- Vendor
- Linux
- Product
- Linux
- Platforms
- Unknown
- Default status
unaffected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 | affected | git | ebb45c2648b1f60715fd283700f651e05e431231 | Unavailable | None listed |
| bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 | affected | git | 09d2407985b8ce3e831f9d4310fe7ac06a6b3ae9 | Unavailable | None listed |
| bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 | affected | git | 36f8534f461222291a74156ab91f3ba9f09b6f93 | Unavailable | None listed |
| bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 | affected | git | 006467ab932698612398f853344a7405164541f4 | Unavailable | None listed |
| bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 | affected | git | b9beed2322f3538b0d2d53307062da4102b8d8d8 | Unavailable | None listed |
| bbf535fd6f06b94b9d07ed6f09397a936d4a58d8 | affected | git | e30453c61e185e914fde83c650e268067b140218 | Unavailable | None listed |
Linux
- Vendor
- Linux
- Product
- Linux
- Platforms
- Unknown
- Default status
affected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 6.0 | affected | Unavailable | Unavailable | Unavailable | None listed |
| 0 | unaffected | semver | 6.0 | Unavailable | None listed |
| 6.1.178 | unaffected | semver | Unavailable | 6.1.* | None listed |
| 6.6.145 | unaffected | semver | Unavailable | 6.6.* | None listed |
| 6.12.96 | unaffected | semver | Unavailable | 6.12.* | None listed |
| 6.18.39 | unaffected | semver | Unavailable | 6.18.* | None listed |
| 7.1.4 | unaffected | semver | Unavailable | 7.1.* | None listed |
| 7.2 | unaffected | original_commit_for_fix | Unavailable | * | None listed |