{"id":"CVE-2023-54220","state":"PUBLISHED","title":"serial: 8250: Fix oops for port->pm on uart_change_pm()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nserial: 8250: Fix oops for port->pm on uart_change_pm()\n\nUnloading a hardware specific 8250 driver can produce error \"Unable to\nhandle kernel paging request at virtual address\" about ten seconds after\nunloading the driver. This happens on uart_hangup() calling\nuart_change_pm().\n\nTurns out commit 04e82793f068 (\"serial: 8250: Reinit port->pm on port\nspecific driver unbind\") was only a partial fix. If the hardware specific\ndriver has initialized port->pm function, we need to clear port->pm too.\nJust reinitializing port->ops does not do this. Otherwise serial8250_pm()\nwill call port->pm() instead of serial8250_do_pm().","publishedAt":"2025-12-30T12:11:15.385Z","updatedAt":"2026-10-15T21:41:42.172Z","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":"490bf37eaabb0a857ed1ae8e75d8854e41662f1c","status":"affected","lessThan":"66f3e55960698c874b0598277913b478ecd29573","versionType":"git"},{"version":"c9e080c3005fd183c56ff8f4d75edb5da0765d2c","status":"affected","lessThan":"720a297b334e85d34099e83d1f375b92c3efedd6","versionType":"git"},{"version":"d5cd2928d31042a7c0a01464f9a8d95be736421d","status":"affected","lessThan":"b653289ca6460a6552c8590b75dfa84a0140a46b","versionType":"git"},{"version":"2c86a1305c1406f45ea780d06953c484ea1d9e6e","status":"affected","lessThan":"bd70d0b28010d560a8be96b44fea86fe2ba016ae","versionType":"git"},{"version":"1ba5594739d858e524ff0f398ee1ebfe0a8b9d41","status":"affected","lessThan":"18e27df4f2b4e257c317ba8076f31a888f6cc64b","versionType":"git"},{"version":"af4d6dbb1a92ea424ad1ba1d0c88c7fa2345d872","status":"affected","lessThan":"0c05493341d6f2097f75f0a5dbb7b53a9e8c5f6c","versionType":"git"},{"version":"04e82793f068d2f0ffe62fcea03d007a8cdc16a7","status":"affected","lessThan":"375806616f8c772c33d40e112530887b37c1a816","versionType":"git"},{"version":"04e82793f068d2f0ffe62fcea03d007a8cdc16a7","status":"affected","lessThan":"dfe2aeb226fd5e19b0ee795f4f6ed8bc494c1534","versionType":"git"},{"version":"8e596aed5f2f98cf3e6e98d6fe1d689f4a319308","status":"affected","versionType":"git"},{"version":"4.14.316","status":"affected","lessThan":"4.14.324","versionType":"semver"},{"version":"4.19.284","status":"affected","lessThan":"4.19.293","versionType":"semver"},{"version":"5.4.244","status":"affected","lessThan":"5.4.255","versionType":"semver"},{"version":"5.10.181","status":"affected","lessThan":"5.10.192","versionType":"semver"},{"version":"5.15.113","status":"affected","lessThan":"5.15.128","versionType":"semver"},{"version":"6.1.30","status":"affected","lessThan":"6.1.47","versionType":"semver"},{"version":"6.3.4","status":"affected","lessThan":"6.4","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/serial/8250/8250_port.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.4","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.4","versionType":"semver"},{"version":"4.14.324","status":"unaffected","lessThanOrEqual":"4.14.*","versionType":"semver"},{"version":"4.19.293","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.255","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.192","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.128","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.47","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.4.12","status":"unaffected","lessThanOrEqual":"6.4.*","versionType":"semver"},{"version":"6.5","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/8250/8250_port.c"]}],"references":["https://git.kernel.org/stable/c/66f3e55960698c874b0598277913b478ecd29573","https://git.kernel.org/stable/c/720a297b334e85d34099e83d1f375b92c3efedd6","https://git.kernel.org/stable/c/b653289ca6460a6552c8590b75dfa84a0140a46b","https://git.kernel.org/stable/c/bd70d0b28010d560a8be96b44fea86fe2ba016ae","https://git.kernel.org/stable/c/18e27df4f2b4e257c317ba8076f31a888f6cc64b","https://git.kernel.org/stable/c/0c05493341d6f2097f75f0a5dbb7b53a9e8c5f6c","https://git.kernel.org/stable/c/375806616f8c772c33d40e112530887b37c1a816","https://git.kernel.org/stable/c/dfe2aeb226fd5e19b0ee795f4f6ed8bc494c1534"],"weaknesses":[],"ingestedAt":"2026-10-29T20:06:42.242Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2023/54xxx/CVE-2023-54220.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2023-54220","state":"PUBLISHED","datePublished":"2025-12-30T12:11:15.385Z","dateUpdated":"2026-10-15T21:41:42.172Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-12-30T12:06:44.501Z"},"containers":{"cna":{"title":"serial: 8250: Fix oops for port->pm on uart_change_pm()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nserial: 8250: Fix oops for port->pm on uart_change_pm()\n\nUnloading a hardware specific 8250 driver can produce error \"Unable to\nhandle kernel paging request at virtual address\" about ten seconds after\nunloading the driver. This happens on uart_hangup() calling\nuart_change_pm().\n\nTurns out commit 04e82793f068 (\"serial: 8250: Reinit port->pm on port\nspecific driver unbind\") was only a partial fix. If the hardware specific\ndriver has initialized port->pm function, we need to clear port->pm too.\nJust reinitializing port->ops does not do this. Otherwise serial8250_pm()\nwill call port->pm() instead of serial8250_do_pm()."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"490bf37eaabb0a857ed1ae8e75d8854e41662f1c","status":"affected","lessThan":"66f3e55960698c874b0598277913b478ecd29573","versionType":"git"},{"version":"c9e080c3005fd183c56ff8f4d75edb5da0765d2c","status":"affected","lessThan":"720a297b334e85d34099e83d1f375b92c3efedd6","versionType":"git"},{"version":"d5cd2928d31042a7c0a01464f9a8d95be736421d","status":"affected","lessThan":"b653289ca6460a6552c8590b75dfa84a0140a46b","versionType":"git"},{"version":"2c86a1305c1406f45ea780d06953c484ea1d9e6e","status":"affected","lessThan":"bd70d0b28010d560a8be96b44fea86fe2ba016ae","versionType":"git"},{"version":"1ba5594739d858e524ff0f398ee1ebfe0a8b9d41","status":"affected","lessThan":"18e27df4f2b4e257c317ba8076f31a888f6cc64b","versionType":"git"},{"version":"af4d6dbb1a92ea424ad1ba1d0c88c7fa2345d872","status":"affected","lessThan":"0c05493341d6f2097f75f0a5dbb7b53a9e8c5f6c","versionType":"git"},{"version":"04e82793f068d2f0ffe62fcea03d007a8cdc16a7","status":"affected","lessThan":"375806616f8c772c33d40e112530887b37c1a816","versionType":"git"},{"version":"04e82793f068d2f0ffe62fcea03d007a8cdc16a7","status":"affected","lessThan":"dfe2aeb226fd5e19b0ee795f4f6ed8bc494c1534","versionType":"git"},{"version":"8e596aed5f2f98cf3e6e98d6fe1d689f4a319308","status":"affected","versionType":"git"},{"version":"4.14.316","status":"affected","lessThan":"4.14.324","versionType":"semver"},{"version":"4.19.284","status":"affected","lessThan":"4.19.293","versionType":"semver"},{"version":"5.4.244","status":"affected","lessThan":"5.4.255","versionType":"semver"},{"version":"5.10.181","status":"affected","lessThan":"5.10.192","versionType":"semver"},{"version":"5.15.113","status":"affected","lessThan":"5.15.128","versionType":"semver"},{"version":"6.1.30","status":"affected","lessThan":"6.1.47","versionType":"semver"},{"version":"6.3.4","status":"affected","lessThan":"6.4","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/serial/8250/8250_port.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.4","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.4","versionType":"semver"},{"version":"4.14.324","status":"unaffected","lessThanOrEqual":"4.14.*","versionType":"semver"},{"version":"4.19.293","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.255","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.192","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.128","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.47","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.4.12","status":"unaffected","lessThanOrEqual":"6.4.*","versionType":"semver"},{"version":"6.5","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/8250/8250_port.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/66f3e55960698c874b0598277913b478ecd29573"},{"url":"https://git.kernel.org/stable/c/720a297b334e85d34099e83d1f375b92c3efedd6"},{"url":"https://git.kernel.org/stable/c/b653289ca6460a6552c8590b75dfa84a0140a46b"},{"url":"https://git.kernel.org/stable/c/bd70d0b28010d560a8be96b44fea86fe2ba016ae"},{"url":"https://git.kernel.org/stable/c/18e27df4f2b4e257c317ba8076f31a888f6cc64b"},{"url":"https://git.kernel.org/stable/c/0c05493341d6f2097f75f0a5dbb7b53a9e8c5f6c"},{"url":"https://git.kernel.org/stable/c/375806616f8c772c33d40e112530887b37c1a816"},{"url":"https://git.kernel.org/stable/c/dfe2aeb226fd5e19b0ee795f4f6ed8bc494c1534"}],"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 - The stale `port->pm` call is reached through local tty operations (open/close/hangup on /dev/ttyS*) and the state is created via local sysfs unbind or module unload; there is no network- or physically-mediated path to the code.\nAC:L - There is no race and no memory-layout dependency — once the hardware-specific 8250 driver is unbound or unloaded, `port->pm` is unconditionally stale and every subsequent `uart_change_pm()` transition dereferences it deterministically (the reporter saw it reliably ~10s later on the automatic hangup).\nPR:L - The dangling call is executed by unprivileged tty operations — an ordinary user with serial-device access (commonly granted via the dialout group on the embedded/industrial systems running 8250_omap/mtk/pxa/exar) opening or closing the port, or simply exiting a process holding it as controlling tty, is enough.\nUI:N - No victim action is needed; the kernel itself invokes `uart_hangup()` → `uart_change_pm()` on process exit and `uart_shutdown()` on close, so the stale pointer fires automatically.\nS:U - The stale function-pointer call and the resulting corruption stay within the kernel's own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - This is a dangling function pointer into freed module text plus MMIO access through a released ioremap mapping — the same class as a use-after-free, which allows an attacker who reclaims the freed region to obtain arbitrary kernel-memory read.\nI:H - An indirect call through a freed code pointer is a direct control-flow hijack primitive, and `omap_8250_pm()`/`exar_pm()` additionally perform `serial_out()` writes through a dangling ioremap cookie, giving an uncontrolled kernel write.\nA:H - The commit documents the concrete result — \"Unable to handle kernel paging request at virtual address\" / \"Internal error: imprecise external abort\" — a kernel oops that kills the affected task and can panic the system."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T09:18:10.284Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14.316","versionEndExcluding":"4.14.324"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19.284","versionEndExcluding":"4.19.293"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4.244","versionEndExcluding":"5.4.255"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10.181","versionEndExcluding":"5.10.192"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15.113","versionEndExcluding":"5.15.128"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1.30","versionEndExcluding":"6.1.47"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.4","versionEndExcluding":"6.4.12"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.4","versionEndExcluding":"6.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.3.4"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2023-54220","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-15T21:39:29.518449Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-15T21:41:42.172Z"}}]}}}