{"id":"CVE-2026-72142","summary":"i2c: imx: fix locked bus on SMBus block-read of 0 (atomic)","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ni2c: imx: fix locked bus on SMBus block-read of 0 (atomic)\n\nSMBus 3.1 6.5.7 allows a Block Read byte count of 0, but the atomic\n(polling) path rejects it as -EPROTO. Worse, it returns without a\nNACK+STOP: the next receive cycle has already started, so the target\nkeeps holding SDA and the bus stays stuck until a power cycle for\nthis i2c controller.\n\nReading I2DR to obtain the count likewise arms the next byte on the\ncount \u003e I2C_SMBUS_BLOCK_MAX path, which also returned -EPROTO directly\nand left the bus held.\n\nHandle both: NACK the in-flight dummy byte (TXAK) and extend msgs-\u003elen so\nthe existing last-byte handling emits STOP; the dummy byte is discarded.\nA count of 0 is a valid empty block read; a count above\nI2C_SMBUS_BLOCK_MAX is still reported as -EPROTO, but only after the bus\nhas been released.\n\nThe interrupt-driven path has the same flaw from a later commit and is\nfixed separately, as it carries a different Fixes: tag and stable range.","modified":"2026-08-18T03:31:28.640734106Z","published":"2026-08-15T05:53:15.489Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72142.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/016ef0f6ca4bc9bf0330ac41bd2ea349759643e3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/60ed00d46616a9232e42ea7a3e3c0273d7cf7543"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6d2c973926d0612360693bc559be2ffde836151b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c882e8cc68fb993700dc21fd6e754001e6297934"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cb2fc37857693b55909fb77dc2c87cfbc1cdc476"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72142.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-72142"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"8e8782c71595a5ad29e234ce6b3d2fce787fb07a"},{"fixed":"016ef0f6ca4bc9bf0330ac41bd2ea349759643e3"},{"fixed":"c882e8cc68fb993700dc21fd6e754001e6297934"},{"fixed":"6d2c973926d0612360693bc559be2ffde836151b"},{"fixed":"60ed00d46616a9232e42ea7a3e3c0273d7cf7543"},{"fixed":"cb2fc37857693b55909fb77dc2c87cfbc1cdc476"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72142.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.16.0"},{"fixed":"6.6.148"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.101"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.40"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72142.json"}}],"schema_version":"1.9.0"}