net: mvpp2: guard flow control update with global_tx_fc in buffer switching
Summary
| CVE | CVE-2026-23438 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-04-03 16:16:25 UTC |
| Updated | 2026-04-23 20:59:22 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: net: mvpp2: guard flow control update with global_tx_fc in buffer switching mvpp2_bm_switch_buffers() unconditionally calls mvpp2_bm_pool_update_priv_fc() when switching between per-cpu and shared buffer pool modes. This function programs CM3 flow control registers via mvpp2_cm3_read()/mvpp2_cm3_write(), which dereference priv->cm3_base without any NULL check. When the CM3 SRAM resource is not present in the device tree (the third reg entry added by commit 60523583b07c ("dts: marvell: add CM3 SRAM memory to cp11x ethernet device tree")), priv->cm3_base remains NULL and priv->global_tx_fc is false. Any operation that triggers mvpp2_bm_switch_buffers(), for example an MTU change that crosses the jumbo frame threshold, will crash: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Mem abort info: ESR = 0x0000000096000006 EC = 0x25: DABT (current EL), IL = 32 bits pc : readl+0x0/0x18 lr : mvpp2_cm3_read.isra.0+0x14/0x20 Call trace: readl+0x0/0x18 mvpp2_bm_pool_update_fc+0x40/0x12c mvpp2_bm_pool_update_priv_fc+0x94/0xd8 mvpp2_bm_switch_buffers.isra.0+0x80/0x1c0 mvpp2_change_mtu+0x140/0x380 __dev_set_mtu+0x1c/0x38 dev_set_mtu_ext+0x78/0x118 dev_set_mtu+0x48/0xa8 dev_ifsioc+0x21c/0x43c dev_ioctl+0x2d8/0x42c sock_ioctl+0x314/0x378 Every other flow control call site in the driver already guards hardware access with either priv->global_tx_fc or port->tx_fc. mvpp2_bm_switch_buffers() is the only place that omits this check. Add the missing priv->global_tx_fc guard to both the disable and re-enable calls in mvpp2_bm_switch_buffers(), consistent with the rest of the driver. |
Risk And Classification
Primary CVSS: v3.1 5.5 MEDIUM from [email protected]
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.000320000 probability, percentile 0.092520000 (date 2026-04-21)
Problem Types: CWE-476
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Operating System | Linux | Linux Kernel | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 3a616b92a9d17448d96a33bf58e69f01457fd43a 0cfcd31f98fc608dc9406bff3fee3a9dd364d014 git | Not specified |
| CNA | Linux | Linux | affected 3a616b92a9d17448d96a33bf58e69f01457fd43a da089f74a993f846685067b14158cb41b879ff29 git | Not specified |
| CNA | Linux | Linux | affected 3a616b92a9d17448d96a33bf58e69f01457fd43a ff0c54f088f7ab91dbbf47cf8244460f99122750 git | Not specified |
| CNA | Linux | Linux | affected 3a616b92a9d17448d96a33bf58e69f01457fd43a 7bd20f4b3ef3044dc55acd5b8ef748a70d29d03f git | Not specified |
| CNA | Linux | Linux | affected 3a616b92a9d17448d96a33bf58e69f01457fd43a 7df2b50cae1a76cbb90b294f3edb61e3e10bf2e9 git | Not specified |
| CNA | Linux | Linux | affected 3a616b92a9d17448d96a33bf58e69f01457fd43a 8baced53a35fc9710f80d6ca016a2c418dc3231f git | Not specified |
| CNA | Linux | Linux | affected 3a616b92a9d17448d96a33bf58e69f01457fd43a 8a63baadf08453f66eb582fdb6dd234f72024723 git | Not specified |
| CNA | Linux | Linux | affected 5.12 | Not specified |
| CNA | Linux | Linux | unaffected 5.12 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.203 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.167 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.130 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.78 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.20 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.19.10 6.19.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.0 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/8a63baadf08453f66eb582fdb6dd234f72024723 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/8baced53a35fc9710f80d6ca016a2c418dc3231f | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/da089f74a993f846685067b14158cb41b879ff29 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/7df2b50cae1a76cbb90b294f3edb61e3e10bf2e9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/7bd20f4b3ef3044dc55acd5b8ef748a70d29d03f | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/0cfcd31f98fc608dc9406bff3fee3a9dd364d014 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/ff0c54f088f7ab91dbbf47cf8244460f99122750 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.