{"id":"CVE-2026-64409","state":"PUBLISHED","title":"Bluetooth: btmtksdio: fix infinite loop in btmtksdio_txrx_work()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: btmtksdio: fix infinite loop in btmtksdio_txrx_work()\n\nEvery once in a while we see a hung btmtksdio_flush() task:\n\n INFO: task kworker/u17:0:189 blocked for more than 122 seconds.\n __cancel_work_timer+0x3f4/0x460\n cancel_work_sync+0x1c/0x2c\n btmtksdio_flush+0x2c/0x40\n hci_dev_open_sync+0x10c4/0x2190\n [..]\n\nIt all boils down to incorrect time_is_before_jiffies() usage in\nbtmtksdio_txrx_work().  The btmtksdio_txrx_work() loop is expected\nto be terminated if running for longer than 5*HZ.  However the\ntimeout check is twisted:  time_is_before_jiffies(old_jiffies + 5*HZ)\nevaluates to true when old_jiffies + 5*HZ is in the past i.e. when a\ntimeout has occurred.  Using OR with time_is_before_jiffies(txrx_timeout)\nmeans that:\n- before the 5-second timeout: the condition is `int_status || false`,\n  so it loops as long as there are pending interrupts.\n- after the 5-second timeout: the condition becomes `int_status || true`,\n  which is always true.\n\nWhen the loop becomes infinite btmtksdio_txrx_work() loop never\nterminates and never releases the SDIO host.\n\nFix loop termination condition to actually enforce a 5*HZ timeout.","publishedAt":"2026-07-25T08:50:50.604Z","updatedAt":"2026-08-17T04:55:07.875Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"26270bc189ea4b5a8356ec99561357fc87f00b32","status":"affected","lessThan":"f6682c23b6fac4780d297ae4662053d17e58fd52","versionType":"git"},{"version":"26270bc189ea4b5a8356ec99561357fc87f00b32","status":"affected","lessThan":"466540e045d01fcacf383a5beb8a2dad2fc53a26","versionType":"git"},{"version":"26270bc189ea4b5a8356ec99561357fc87f00b32","status":"affected","lessThan":"7b429d611060e87752e848851815537963726493","versionType":"git"},{"version":"26270bc189ea4b5a8356ec99561357fc87f00b32","status":"affected","lessThan":"0039bdde36b23ccf1196635f1d52c5490481544d","versionType":"git"},{"version":"26270bc189ea4b5a8356ec99561357fc87f00b32","status":"affected","lessThan":"0f0a83e26a9c7fd4b243c315ce07161d2496d83d","versionType":"git"},{"version":"26270bc189ea4b5a8356ec99561357fc87f00b32","status":"affected","lessThan":"a257407e2bbbb099ed427719a50563f67fa366d8","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/bluetooth/btmtksdio.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.17","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.17","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.96","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.39","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.4","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/bluetooth/btmtksdio.c"]}],"references":["https://git.kernel.org/stable/c/f6682c23b6fac4780d297ae4662053d17e58fd52","https://git.kernel.org/stable/c/466540e045d01fcacf383a5beb8a2dad2fc53a26","https://git.kernel.org/stable/c/7b429d611060e87752e848851815537963726493","https://git.kernel.org/stable/c/0039bdde36b23ccf1196635f1d52c5490481544d","https://git.kernel.org/stable/c/0f0a83e26a9c7fd4b243c315ce07161d2496d83d","https://git.kernel.org/stable/c/a257407e2bbbb099ed427719a50563f67fa366d8"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/64xxx/CVE-2026-64409.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64409","state":"PUBLISHED","datePublished":"2026-07-25T08:50:50.604Z","dateUpdated":"2026-08-17T04:55:07.875Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T15:36:31.786Z"},"containers":{"cna":{"title":"Bluetooth: btmtksdio: fix infinite loop in btmtksdio_txrx_work()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: btmtksdio: fix infinite loop in btmtksdio_txrx_work()\n\nEvery once in a while we see a hung btmtksdio_flush() task:\n\n INFO: task kworker/u17:0:189 blocked for more than 122 seconds.\n __cancel_work_timer+0x3f4/0x460\n cancel_work_sync+0x1c/0x2c\n btmtksdio_flush+0x2c/0x40\n hci_dev_open_sync+0x10c4/0x2190\n [..]\n\nIt all boils down to incorrect time_is_before_jiffies() usage in\nbtmtksdio_txrx_work().  The btmtksdio_txrx_work() loop is expected\nto be terminated if running for longer than 5*HZ.  However the\ntimeout check is twisted:  time_is_before_jiffies(old_jiffies + 5*HZ)\nevaluates to true when old_jiffies + 5*HZ is in the past i.e. when a\ntimeout has occurred.  Using OR with time_is_before_jiffies(txrx_timeout)\nmeans that:\n- before the 5-second timeout: the condition is `int_status || false`,\n  so it loops as long as there are pending interrupts.\n- after the 5-second timeout: the condition becomes `int_status || true`,\n  which is always true.\n\nWhen the loop becomes infinite btmtksdio_txrx_work() loop never\nterminates and never releases the SDIO host.\n\nFix loop termination condition to actually enforce a 5*HZ timeout."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"26270bc189ea4b5a8356ec99561357fc87f00b32","status":"affected","lessThan":"f6682c23b6fac4780d297ae4662053d17e58fd52","versionType":"git"},{"version":"26270bc189ea4b5a8356ec99561357fc87f00b32","status":"affected","lessThan":"466540e045d01fcacf383a5beb8a2dad2fc53a26","versionType":"git"},{"version":"26270bc189ea4b5a8356ec99561357fc87f00b32","status":"affected","lessThan":"7b429d611060e87752e848851815537963726493","versionType":"git"},{"version":"26270bc189ea4b5a8356ec99561357fc87f00b32","status":"affected","lessThan":"0039bdde36b23ccf1196635f1d52c5490481544d","versionType":"git"},{"version":"26270bc189ea4b5a8356ec99561357fc87f00b32","status":"affected","lessThan":"0f0a83e26a9c7fd4b243c315ce07161d2496d83d","versionType":"git"},{"version":"26270bc189ea4b5a8356ec99561357fc87f00b32","status":"affected","lessThan":"a257407e2bbbb099ed427719a50563f67fa366d8","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/bluetooth/btmtksdio.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.17","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.17","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.96","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.39","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.4","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/bluetooth/btmtksdio.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/f6682c23b6fac4780d297ae4662053d17e58fd52"},{"url":"https://git.kernel.org/stable/c/466540e045d01fcacf383a5beb8a2dad2fc53a26"},{"url":"https://git.kernel.org/stable/c/7b429d611060e87752e848851815537963726493"},{"url":"https://git.kernel.org/stable/c/0039bdde36b23ccf1196635f1d52c5490481544d"},{"url":"https://git.kernel.org/stable/c/0f0a83e26a9c7fd4b243c315ce07161d2496d83d"},{"url":"https://git.kernel.org/stable/c/a257407e2bbbb099ed427719a50563f67fa366d8"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-17T04:55:07.875Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.17","versionEndExcluding":"6.1.178"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.17","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.17","versionEndExcluding":"6.12.96"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.17","versionEndExcluding":"6.18.39"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.17","versionEndExcluding":"7.1.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.17","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}