{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-74463", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.901Z", "datePublished": "2026-08-15T12:27:03.176Z", "dateUpdated": "2026-08-19T16:37:02.602Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-19T16:37:02.602Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ni2c: jz4780: Cache host clock rate at probe to prevent CCF prepare_lock deadlock\n\nFix a severe AB/BA deadlock between the Common Clock Framework (CCF)\nand the I2C adapter lock, which triggers when an I2C-controlled clock\ngenerator client (like the Si5351) is registered or modified under the CCF.\n\nDuring an i2c client clock (generator) frequency change, the CCF acquires its global\n'prepare_lock' mutex and the driver calls i2c_transfer() to update the client's\nchip registers, stalling for the adapter's I2C bus lock.\n\nConcurrently, an independent, parallel transfer on the same bus (e.g., a GPIO\nexpander handling LEDs) can hold the I2C adapter lock. Inside this parallel\ntransfer path, jz4780_i2c_set_speed() calls clk_get_rate() on the host\ncontroller's input clock to calculate bus timings. This call attempts to acquire\nthe blocked CCF 'prepare_lock', creating a circular dependency that freezes\nthe system.\n\nThe jz4780 host controller clock itself is static and never changes at runtime.\n\nHowever, calling clk_get_rate() inside the active transfer path introduces\nan unnecessary dependency on the CCF internal locks.\n\nEliminate this synchronous clk_get_rate() call from the active transfer\npath by caching the static host peripheral clock rate once - inside the private\njz4780_i2c structure during jz4780_i2c_probe(). Update jz4780_i2c_set_speed()\nto use this cached value, safely decoupling active I2C transactions from the\nCCF internal locks without any risk of stale timings.\n\nAssisted-by web based Google AI (pinpointing the bug and writing the message)." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/i2c/busses/i2c-jz4780.c" ], "versions": [ { "version": "ba92222ed63a12d09120df9b92f56cc990abac19", "lessThan": "cc111696ef420f6bb552b2526530067977f0b406", "status": "affected", "versionType": "git" }, { "version": "ba92222ed63a12d09120df9b92f56cc990abac19", "lessThan": "f96a719d9f8a797105ec5cacf568ab128e33391f", "status": "affected", "versionType": "git" }, { "version": "ba92222ed63a12d09120df9b92f56cc990abac19", "lessThan": "deffad5bb4f8b4f09e46252f24754ddc9960b244", "status": "affected", "versionType": "git" }, { "version": "ba92222ed63a12d09120df9b92f56cc990abac19", "lessThan": "14429dc1c756c35e106f01ff09cadccb82f5531d", "status": "affected", "versionType": "git" }, { "version": "ba92222ed63a12d09120df9b92f56cc990abac19", "lessThan": "b6cb47e186abba85a3b08aa3023067ab82577286", "status": "affected", "versionType": "git" }, { "version": "ba92222ed63a12d09120df9b92f56cc990abac19", "lessThan": "19b783335d62e7a2367436a6e1f1b37da1878360", "status": "affected", "versionType": "git" }, { "version": "ba92222ed63a12d09120df9b92f56cc990abac19", "lessThan": "aa1944b52d6492c48bdd17046578aa0d953546e6", "status": "affected", "versionType": "git" }, { "version": "ba92222ed63a12d09120df9b92f56cc990abac19", "lessThan": "d99607c888f26e8a4e9fe9772860cef4aff86bb4", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/i2c/busses/i2c-jz4780.c" ], "versions": [ { "version": "4.1", "status": "affected" }, { "version": "0", "lessThan": "4.1", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.265", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.216", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.183", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.151", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.103", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.44", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.8", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "5.10.265" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "5.15.216" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "6.1.183" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "6.6.151" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "6.12.103" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "6.18.44" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "7.1.8" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/cc111696ef420f6bb552b2526530067977f0b406" }, { "url": "https://git.kernel.org/stable/c/f96a719d9f8a797105ec5cacf568ab128e33391f" }, { "url": "https://git.kernel.org/stable/c/deffad5bb4f8b4f09e46252f24754ddc9960b244" }, { "url": "https://git.kernel.org/stable/c/14429dc1c756c35e106f01ff09cadccb82f5531d" }, { "url": "https://git.kernel.org/stable/c/b6cb47e186abba85a3b08aa3023067ab82577286" }, { "url": "https://git.kernel.org/stable/c/19b783335d62e7a2367436a6e1f1b37da1878360" }, { "url": "https://git.kernel.org/stable/c/aa1944b52d6492c48bdd17046578aa0d953546e6" }, { "url": "https://git.kernel.org/stable/c/d99607c888f26e8a4e9fe9772860cef4aff86bb4" } ], "title": "i2c: jz4780: Cache host clock rate at probe to prevent CCF prepare_lock deadlock", "x_generator": { "engine": "bippy-1.2.0" } } } }