{"id":"CVE-2026-64528","state":"PUBLISHED","title":"tty: serial: samsung: Remove redundant port lock acquisition in rx helpers","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntty: serial: samsung: Remove redundant port lock acquisition in rx helpers\n\nSashiko identified a deadlock when the console flow is engaged [1].\n\nWhen console flow control is enabled (UPF_CONS_FLOW),\ns3c24xx_serial_stop_tx() calls s3c24xx_serial_rx_enable() and\ns3c24xx_serial_start_tx() calls s3c24xx_serial_rx_disable().\n\nThe serial core framework invokes the .stop_tx() and .start_tx()\ncallbacks with the port->lock spinlock already held. Furthermore, all\ninternal driver paths that invoke stop_tx (such as the DMA TX\ncompletion handler s3c24xx_serial_tx_dma_complete() or the PIO TX IRQ\nhandler s3c24xx_serial_tx_irq()) also acquire port->lock prior to\ncalling it. (Note that s3c24xx_serial_start_tx() is only invoked by the\nserial core).\n\nHowever, s3c24xx_serial_rx_enable() and s3c24xx_serial_rx_disable()\nunconditionally attempt to acquire port->lock again using\nuart_port_lock_irqsave(). Since spinlocks are not recursive, this\ncauses a deadlock on the same CPU when console flow control is engaged.\n\nRemove the redundant lock acquisition from both rx helper functions.","publishedAt":"2026-07-25T09:20:51.774Z","updatedAt":"2026-07-25T09:20:51.774Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"ee9eb72be95490602c493db050c73d925c3a4d74","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"10014eb7eee351f7b587f8ac85830f0c9343cb9a","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"f4c3e63fa8639aedf96fb200d9939945a9eed51e","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"a9c22e0f93ba18322a6623ecdda2f0cd858ca350","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"14143ec10d69f42806b5d7b046f0fd1b835831ae","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"9fd48937046efc9abb89379d63ee9cc5c661d711","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"9c92b42207978559e32903c3098aaf5c5b5788b2","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"a3bb136bff5e6a5e48cdd813246c9c4686feaaa9","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/serial/samsung_tty.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.27","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.27","versionType":"semver"},{"version":"5.10.259","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.210","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.176","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.143","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.93","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.35","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.12","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/serial/samsung_tty.c"]}],"references":["https://git.kernel.org/stable/c/ee9eb72be95490602c493db050c73d925c3a4d74","https://git.kernel.org/stable/c/10014eb7eee351f7b587f8ac85830f0c9343cb9a","https://git.kernel.org/stable/c/f4c3e63fa8639aedf96fb200d9939945a9eed51e","https://git.kernel.org/stable/c/a9c22e0f93ba18322a6623ecdda2f0cd858ca350","https://git.kernel.org/stable/c/14143ec10d69f42806b5d7b046f0fd1b835831ae","https://git.kernel.org/stable/c/9fd48937046efc9abb89379d63ee9cc5c661d711","https://git.kernel.org/stable/c/9c92b42207978559e32903c3098aaf5c5b5788b2","https://git.kernel.org/stable/c/a3bb136bff5e6a5e48cdd813246c9c4686feaaa9"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/64xxx/CVE-2026-64528.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-64528","state":"PUBLISHED","datePublished":"2026-07-25T09:20:51.774Z","dateUpdated":"2026-07-25T09:20:51.774Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T15:36:31.794Z"},"containers":{"cna":{"title":"tty: serial: samsung: Remove redundant port lock acquisition in rx helpers","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntty: serial: samsung: Remove redundant port lock acquisition in rx helpers\n\nSashiko identified a deadlock when the console flow is engaged [1].\n\nWhen console flow control is enabled (UPF_CONS_FLOW),\ns3c24xx_serial_stop_tx() calls s3c24xx_serial_rx_enable() and\ns3c24xx_serial_start_tx() calls s3c24xx_serial_rx_disable().\n\nThe serial core framework invokes the .stop_tx() and .start_tx()\ncallbacks with the port->lock spinlock already held. Furthermore, all\ninternal driver paths that invoke stop_tx (such as the DMA TX\ncompletion handler s3c24xx_serial_tx_dma_complete() or the PIO TX IRQ\nhandler s3c24xx_serial_tx_irq()) also acquire port->lock prior to\ncalling it. (Note that s3c24xx_serial_start_tx() is only invoked by the\nserial core).\n\nHowever, s3c24xx_serial_rx_enable() and s3c24xx_serial_rx_disable()\nunconditionally attempt to acquire port->lock again using\nuart_port_lock_irqsave(). Since spinlocks are not recursive, this\ncauses a deadlock on the same CPU when console flow control is engaged.\n\nRemove the redundant lock acquisition from both rx helper functions."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"ee9eb72be95490602c493db050c73d925c3a4d74","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"10014eb7eee351f7b587f8ac85830f0c9343cb9a","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"f4c3e63fa8639aedf96fb200d9939945a9eed51e","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"a9c22e0f93ba18322a6623ecdda2f0cd858ca350","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"14143ec10d69f42806b5d7b046f0fd1b835831ae","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"9fd48937046efc9abb89379d63ee9cc5c661d711","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"9c92b42207978559e32903c3098aaf5c5b5788b2","versionType":"git"},{"version":"b497549a035c2a81b71c7a27f2b00c8a16c09423","status":"affected","lessThan":"a3bb136bff5e6a5e48cdd813246c9c4686feaaa9","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/serial/samsung_tty.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.27","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.27","versionType":"semver"},{"version":"5.10.259","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.210","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.176","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.143","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.93","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.35","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.12","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/serial/samsung_tty.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/ee9eb72be95490602c493db050c73d925c3a4d74"},{"url":"https://git.kernel.org/stable/c/10014eb7eee351f7b587f8ac85830f0c9343cb9a"},{"url":"https://git.kernel.org/stable/c/f4c3e63fa8639aedf96fb200d9939945a9eed51e"},{"url":"https://git.kernel.org/stable/c/a9c22e0f93ba18322a6623ecdda2f0cd858ca350"},{"url":"https://git.kernel.org/stable/c/14143ec10d69f42806b5d7b046f0fd1b835831ae"},{"url":"https://git.kernel.org/stable/c/9fd48937046efc9abb89379d63ee9cc5c661d711"},{"url":"https://git.kernel.org/stable/c/9c92b42207978559e32903c3098aaf5c5b5788b2"},{"url":"https://git.kernel.org/stable/c/a3bb136bff5e6a5e48cdd813246c9c4686feaaa9"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-07-25T09:20:51.774Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"5.10.259"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"5.15.210"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"6.1.176"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"6.6.143"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"6.12.93"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"6.18.35"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"7.0.12"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.27","versionEndExcluding":"7.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}