{"id":"CVE-2026-23438","revision":"e816d2ebc72a434a81e84200d47d7b94","records":[{"revision":"e816d2ebc72a434a81e84200d47d7b94","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-23438","aliases":[],"title":"net: mvpp2: guard flow control update with global_tx_fc in buffer switching","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: mvpp2: guard flow control update with global_tx_fc in buffer switching\n\nmvpp2_bm_switch_buffers() unconditionally calls\nmvpp2_bm_pool_update_priv_fc() when switching between per-cpu and\nshared buffer pool modes. This function programs CM3 flow control\nregisters via mvpp2_cm3_read()/mvpp2_cm3_write(), which dereference\npriv->cm3_base without any NULL check.\n\nWhen the CM3 SRAM resource is not present in the device tree (the\nthird reg entry added by commit 60523583b07c (\"dts: marvell: add CM3\nSRAM memory to cp11x ethernet device tree\")), priv->cm3_base remains\nNULL and priv->global_tx_fc is false. Any operation that triggers\nmvpp2_bm_switch_buffers(), for example an MTU change that crosses\nthe jumbo frame threshold, will crash:\n\n Unable to handle kernel NULL pointer dereference at\n virtual address 0000000000000000\n Mem abort info:\n ESR = 0x0000000096000006\n EC = 0x25: DABT (current EL), IL = 32 bits\n pc : readl+0x0/0x18\n lr : mvpp2_cm3_read.isra.0+0x14/0x20\n Call trace:\n readl+0x0/0x18\n mvpp2_bm_pool_update_fc+0x40/0x12c\n mvpp2_bm_pool_update_priv_fc+0x94/0xd8\n mvpp2_bm_switch_buffers.isra.0+0x80/0x1c0\n mvpp2_change_mtu+0x140/0x380\n __dev_set_mtu+0x1c/0x38\n dev_set_mtu_ext+0x78/0x118\n dev_set_mtu+0x48/0xa8\n dev_ifsioc+0x21c/0x43c\n dev_ioctl+0x2d8/0x42c\n sock_ioctl+0x314/0x378\n\nEvery other flow control call site in the driver already guards\nhardware access with either priv->global_tx_fc or port->tx_fc.\nmvpp2_bm_switch_buffers() is the only place that omits this check.\n\nAdd the missing priv->global_tx_fc guard to both the disable and\nre-enable calls in mvpp2_bm_switch_buffers(), consistent with the\nrest of the driver.","state":0,"publishedAt":"2026-04-03T15:15:22.701+00:00","modifiedAt":"2026-10-15T01:14:58.956+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"unaffected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c\"\n ],\n \"versions\": [\n {\n \"version\": \"3a616b92a9d17448d96a33bf58e69f01457fd43a\",\n \"lessThan\": \"0cfcd31f98fc608dc9406bff3fee3a9dd364d014\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"3a616b92a9d17448d96a33bf58e69f01457fd43a\",\n \"lessThan\": \"da089f74a993f846685067b14158cb41b879ff29\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"3a616b92a9d17448d96a33bf58e69f01457fd43a\",\n \"lessThan\": \"ff0c54f088f7ab91dbbf47cf8244460f99122750\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"3a616b92a9d17448d96a33bf58e69f01457fd43a\",\n \"lessThan\": \"7bd20f4b3ef3044dc55acd5b8ef748a70d29d03f\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"3a616b92a9d17448d96a33bf58e69f01457fd43a\",\n \"lessThan\": \"7df2b50cae1a76cbb90b294f3edb61e3e10bf2e9\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"3a616b92a9d17448d96a33bf58e69f01457fd43a\",\n \"lessThan\": \"8baced53a35fc9710f80d6ca016a2c418dc3231f\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n },\n {\n \"version\": \"3a616b92a9d17448d96a33bf58e69f01457fd43a\",\n \"lessThan\": \"8a63baadf08453f66eb582fdb6dd234f72024723\",\n \"status\": \"affected\",\n \"versionType\": \"git\"\n }\n ]\n }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n \"product\": \"Linux\",\n \"vendor\": \"Linux\",\n \"defaultStatus\": \"affected\",\n \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n \"programFiles\": [\n \"drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c\"\n ],\n \"versions\": [\n {\n \"version\": \"5.12\",\n \"status\": \"affected\"\n },\n {\n \"version\": \"0\",\n \"lessThan\": \"5.12\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"5.15.203\",\n \"lessThanOrEqual\": \"5.15.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.1.167\",\n \"lessThanOrEqual\": \"6.1.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.6.130\",\n \"lessThanOrEqual\": \"6.6.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.12.78\",\n \"lessThanOrEqual\": \"6.12.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.18.20\",\n \"lessThanOrEqual\": \"6.18.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"6.19.10\",\n \"lessThanOrEqual\": \"6.19.*\",\n \"status\": \"unaffected\",\n \"versionType\": \"semver\"\n },\n {\n \"version\": \"7.0\",\n \"lessThanOrEqual\": \"*\",\n \"status\": \"unaffected\",\n \"versionType\": \"original_commit_for_fix\"\n }\n ]\n }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/0cfcd31f98fc608dc9406bff3fee3a9dd364d014","https://git.kernel.org/stable/c/da089f74a993f846685067b14158cb41b879ff29","https://git.kernel.org/stable/c/ff0c54f088f7ab91dbbf47cf8244460f99122750","https://git.kernel.org/stable/c/7bd20f4b3ef3044dc55acd5b8ef748a70d29d03f","https://git.kernel.org/stable/c/7df2b50cae1a76cbb90b294f3edb61e3e10bf2e9","https://git.kernel.org/stable/c/8baced53a35fc9710f80d6ca016a2c418dc3231f","https://git.kernel.org/stable/c/8a63baadf08453f66eb582fdb6dd234f72024723"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-23438","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-23438","identifiers":["CVE-2026-23438"]},"retained":false,"historicalAffected":[]}],"coverage":[]}