{"api_version":"1","generated_at":"2026-08-22T19:33:01+00:00","cve":"CVE-2026-74655","urls":{"html":"https://cve.report/CVE-2026-74655","api":"https://cve.report/api/cve/CVE-2026-74655.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-74655","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-74655"},"summary":{"title":"serial: qcom-geni: fix TX DMA buffer flush","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nserial: qcom-geni: fix TX DMA buffer flush\n\nWhen transmit flushing a qcom-geni UART during an ongoing TX DMA, the\nUART gets stuck infinitely repeating corrupted TX DMA frames.\n\nThe DMA-mode uart_ops does not provide a flush_buffer callback, so an\nin-flight transfer can complete after serial core has reset the transmit\nkfifo, underflowing its length and resubmitting page-sized transfers\nindefinitely. Add one that stops the transfer and clears tx_remaining\nand tx_queued.\n\nThe stop path was also broken: it unmapped the buffer while the serial\nengine could still read it, and never reset the TX DMA state machine.\nCancel the main sequencer command first, then reset the state machine\nand wait for it before unmapping. Drop the early return so a pending\nmapping is also cleaned up when the main command is inactive.\n\nThe bug can be triggered from userspace with a large write immediately\nfollowed by TCOFLUSH. A following tcdrain will hang forever. The bug was\nreproduced and this fix was validated on Arduino Uno Q (QRB2210)\nusing /dev/ttyHS1.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-22 16:16:39","updated_at":"2026-08-22 16:16:39"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/313ae287442e5e8d3f7b53b73f37d384bda072d0","name":"https://git.kernel.org/stable/c/313ae287442e5e8d3f7b53b73f37d384bda072d0","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/1c31e2377f4c1bb110ca7f6e597b2253a7440c37","name":"https://git.kernel.org/stable/c/1c31e2377f4c1bb110ca7f6e597b2253a7440c37","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b1801c0d40f62778b613334de5840aba10a564d5","name":"https://git.kernel.org/stable/c/b1801c0d40f62778b613334de5840aba10a564d5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/e3c04834ae1ab5e9cfbe8ac54ec734aa4774249d","name":"https://git.kernel.org/stable/c/e3c04834ae1ab5e9cfbe8ac54ec734aa4774249d","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-74655","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74655","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2aaa43c7077833301c237684cd7bc9ae5e3dec95 313ae287442e5e8d3f7b53b73f37d384bda072d0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2aaa43c7077833301c237684cd7bc9ae5e3dec95 1c31e2377f4c1bb110ca7f6e597b2253a7440c37 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2aaa43c7077833301c237684cd7bc9ae5e3dec95 b1801c0d40f62778b613334de5840aba10a564d5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2aaa43c7077833301c237684cd7bc9ae5e3dec95 e3c04834ae1ab5e9cfbe8ac54ec734aa4774249d git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.3","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.3 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.104 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.45 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.9 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/tty/serial/qcom_geni_serial.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"313ae287442e5e8d3f7b53b73f37d384bda072d0","status":"affected","version":"2aaa43c7077833301c237684cd7bc9ae5e3dec95","versionType":"git"},{"lessThan":"1c31e2377f4c1bb110ca7f6e597b2253a7440c37","status":"affected","version":"2aaa43c7077833301c237684cd7bc9ae5e3dec95","versionType":"git"},{"lessThan":"b1801c0d40f62778b613334de5840aba10a564d5","status":"affected","version":"2aaa43c7077833301c237684cd7bc9ae5e3dec95","versionType":"git"},{"lessThan":"e3c04834ae1ab5e9cfbe8ac54ec734aa4774249d","status":"affected","version":"2aaa43c7077833301c237684cd7bc9ae5e3dec95","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/tty/serial/qcom_geni_serial.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.3"},{"lessThan":"6.3","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.104","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.45","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.9","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.104","versionStartIncluding":"6.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.45","versionStartIncluding":"6.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.9","versionStartIncluding":"6.3","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2","versionStartIncluding":"6.3","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nserial: qcom-geni: fix TX DMA buffer flush\n\nWhen transmit flushing a qcom-geni UART during an ongoing TX DMA, the\nUART gets stuck infinitely repeating corrupted TX DMA frames.\n\nThe DMA-mode uart_ops does not provide a flush_buffer callback, so an\nin-flight transfer can complete after serial core has reset the transmit\nkfifo, underflowing its length and resubmitting page-sized transfers\nindefinitely. Add one that stops the transfer and clears tx_remaining\nand tx_queued.\n\nThe stop path was also broken: it unmapped the buffer while the serial\nengine could still read it, and never reset the TX DMA state machine.\nCancel the main sequencer command first, then reset the state machine\nand wait for it before unmapping. Drop the early return so a pending\nmapping is also cleaned up when the main command is inactive.\n\nThe bug can be triggered from userspace with a large write immediately\nfollowed by TCOFLUSH. A following tcdrain will hang forever. The bug was\nreproduced and this fix was validated on Arduino Uno Q (QRB2210)\nusing /dev/ttyHS1."}],"providerMetadata":{"dateUpdated":"2026-08-22T15:32:29.993Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/313ae287442e5e8d3f7b53b73f37d384bda072d0"},{"url":"https://git.kernel.org/stable/c/1c31e2377f4c1bb110ca7f6e597b2253a7440c37"},{"url":"https://git.kernel.org/stable/c/b1801c0d40f62778b613334de5840aba10a564d5"},{"url":"https://git.kernel.org/stable/c/e3c04834ae1ab5e9cfbe8ac54ec734aa4774249d"}],"title":"serial: qcom-geni: fix TX DMA buffer flush","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-74655","datePublished":"2026-08-22T15:32:29.993Z","dateReserved":"2026-08-15T05:44:03.923Z","dateUpdated":"2026-08-22T15:32:29.993Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-22 16:16:39","lastModifiedDate":"2026-08-22 16:16:39","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"74655","Ordinal":"1","Title":"serial: qcom-geni: fix TX DMA buffer flush","CVE":"CVE-2026-74655","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"74655","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nserial: qcom-geni: fix TX DMA buffer flush\n\nWhen transmit flushing a qcom-geni UART during an ongoing TX DMA, the\nUART gets stuck infinitely repeating corrupted TX DMA frames.\n\nThe DMA-mode uart_ops does not provide a flush_buffer callback, so an\nin-flight transfer can complete after serial core has reset the transmit\nkfifo, underflowing its length and resubmitting page-sized transfers\nindefinitely. Add one that stops the transfer and clears tx_remaining\nand tx_queued.\n\nThe stop path was also broken: it unmapped the buffer while the serial\nengine could still read it, and never reset the TX DMA state machine.\nCancel the main sequencer command first, then reset the state machine\nand wait for it before unmapping. Drop the early return so a pending\nmapping is also cleaned up when the main command is inactive.\n\nThe bug can be triggered from userspace with a large write immediately\nfollowed by TCOFLUSH. A following tcdrain will hang forever. The bug was\nreproduced and this fix was validated on Arduino Uno Q (QRB2210)\nusing /dev/ttyHS1.","Type":"Description","Title":"serial: qcom-geni: fix TX DMA buffer flush"}]}}}