{"id":"CVE-2026-99050","state":"PUBLISHED","title":"gpio: mpsse: fix race when arming the IRQ poll worker","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ngpio: mpsse: fix race when arming the IRQ poll worker\n\ngpio_mpsse_irq_enable() arms the poll worker before publishing it:\nschedule_work() runs before the worker is added to priv->workers. If\ngpio_mpsse_disconnect() walks the list in that window it misses the\nworker, and once disconnect returns, the USB core frees mpsse_priv\nwhile the orphaned gpio_mpsse_poll() work keeps accessing it, causing\na use-after-free.\n\nFix this by publishing and arming the worker in one irq_spin\ncritical section. Teardown walks the same list under irq_spin, so a\nworker found on the list is guaranteed to be armed, and\ncancel_work_sync() handles it whether it is queued or running.\n\nA worker armed after the disconnect walk would still be missed, so\nalso set a new priv->dying flag under irq_spin before the teardown\nwalk, and check it in the same critical section, freeing it via\nkfree_rcu() instead when the device is going away, since kfree()\nwould be called with the IRQ core's raw spinlock held and may sleep\non PREEMPT_RT. schedule_work() is safe to call with irq_spin held,\nand the next probe gets a fresh mpsse_priv, so the flag never needs\nto be cleared.\n\nThis issue was found by an in-house static analysis tool.","publishedAt":"2026-10-23T12:22:29.204Z","updatedAt":"2026-10-24T14:10:11.370Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"472d900c8bcac301ae0e40fdca7db799bd989ff5","status":"affected","lessThan":"76390ac0bca7e5058b7482eb4d951c3bda5df812","versionType":"git"},{"version":"179ef1127d7a4f09f0e741fa9f30b8a8e7886271","status":"affected","lessThan":"c0071ee496e1228976c72b096f529503222708a0","versionType":"git"},{"version":"179ef1127d7a4f09f0e741fa9f30b8a8e7886271","status":"affected","lessThan":"7efa1a1953cd6b20b23a3524d5b4b81789c6ef25","versionType":"git"},{"version":"6.18.6","status":"affected","lessThan":"6.18.57","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpio/gpio-mpsse.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.19","versionType":"semver"},{"version":"6.18.57","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.11","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpio/gpio-mpsse.c"]}],"references":["https://git.kernel.org/stable/c/76390ac0bca7e5058b7482eb4d951c3bda5df812","https://git.kernel.org/stable/c/c0071ee496e1228976c72b096f529503222708a0","https://git.kernel.org/stable/c/7efa1a1953cd6b20b23a3524d5b4b81789c6ef25"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/99xxx/CVE-2026-99050.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-99050","state":"PUBLISHED","datePublished":"2026-10-23T12:22:29.204Z","dateUpdated":"2026-10-24T14:10:11.370Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:25:14.388Z"},"containers":{"cna":{"title":"gpio: mpsse: fix race when arming the IRQ poll worker","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ngpio: mpsse: fix race when arming the IRQ poll worker\n\ngpio_mpsse_irq_enable() arms the poll worker before publishing it:\nschedule_work() runs before the worker is added to priv->workers. If\ngpio_mpsse_disconnect() walks the list in that window it misses the\nworker, and once disconnect returns, the USB core frees mpsse_priv\nwhile the orphaned gpio_mpsse_poll() work keeps accessing it, causing\na use-after-free.\n\nFix this by publishing and arming the worker in one irq_spin\ncritical section. Teardown walks the same list under irq_spin, so a\nworker found on the list is guaranteed to be armed, and\ncancel_work_sync() handles it whether it is queued or running.\n\nA worker armed after the disconnect walk would still be missed, so\nalso set a new priv->dying flag under irq_spin before the teardown\nwalk, and check it in the same critical section, freeing it via\nkfree_rcu() instead when the device is going away, since kfree()\nwould be called with the IRQ core's raw spinlock held and may sleep\non PREEMPT_RT. schedule_work() is safe to call with irq_spin held,\nand the next probe gets a fresh mpsse_priv, so the flag never needs\nto be cleared.\n\nThis issue was found by an in-house static analysis tool."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"472d900c8bcac301ae0e40fdca7db799bd989ff5","status":"affected","lessThan":"76390ac0bca7e5058b7482eb4d951c3bda5df812","versionType":"git"},{"version":"179ef1127d7a4f09f0e741fa9f30b8a8e7886271","status":"affected","lessThan":"c0071ee496e1228976c72b096f529503222708a0","versionType":"git"},{"version":"179ef1127d7a4f09f0e741fa9f30b8a8e7886271","status":"affected","lessThan":"7efa1a1953cd6b20b23a3524d5b4b81789c6ef25","versionType":"git"},{"version":"6.18.6","status":"affected","lessThan":"6.18.57","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpio/gpio-mpsse.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.19","versionType":"semver"},{"version":"6.18.57","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.11","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/gpio/gpio-mpsse.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/76390ac0bca7e5058b7482eb4d951c3bda5df812"},{"url":"https://git.kernel.org/stable/c/c0071ee496e1228976c72b096f529503222708a0"},{"url":"https://git.kernel.org/stable/c/7efa1a1953cd6b20b23a3524d5b4b81789c6ef25"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - A local process can race GPIO_V2_GET_LINE_IOCTL -> linereq_create() -> edge_detector_setup() -> request_threaded_irq() -> gpio_mpsse_irq_enable() against USBDEVFS_IOCTL/USBDEVFS_DISCONNECT -> usb_driver_release_interface() -> gpio_mpsse_disconnect(); no network input reaches the bug.\nAC:L - The attacker can issue the GPIO line-event request and USBFS unbind concurrently and repeat after rebinding; both sides of the schedule_work()-before-list_add() window are attacker-controlled.\nPR:L - Neither gpio_ioctl() nor the USBDEVFS_DISCONNECT path performs a capability check; the process only needs non-root DAC/ACL access to /dev/gpiochipN and writable access to the matching /dev/bus/usb node.\nUI:N - The same process submits the line-event and USB disconnect ioctls that create the race, so no action by another user is required.\nS:U - The freed mpsse_priv and orphaned gpio_mpsse_poll() worker are both in the host kernel; the path crosses no VM, IOMMU, or other security authority.\nC:H - gpio_mpsse_poll() continues through attacker-reclaimable mpsse_priv fields, including GPIO, IRQ-domain, USB-buffer, and interface pointers; the resulting UAF and write primitive can yield kernel code execution and unrestricted reads.\nI:H - gpio_mpsse_poll() locks and traverses priv->workers after priv is freed; reclaiming that allocation lets controlled list pointers reach list_del(), providing attacker-directed kernel writes and control-flow corruption.\nA:H - The orphaned gpio_mpsse_poll() can access freed mutex, spinlock, and list state, or use the NULL/stale priv->intf in MPSSE I/O, causing an oops or kernel panic."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-24T14:10:11.370Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.18.6","versionEndExcluding":"6.18.57"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19","versionEndExcluding":"7.2.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.19","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}