{"id":"CVE-2026-53051","state":"PUBLISHED","title":"PCI: tegra194: Fix CBB timeout caused by DBI access before core power-on","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nPCI: tegra194: Fix CBB timeout caused by DBI access before core power-on\n\nWhen PERST# is deasserted twice (assert -> deassert -> assert -> deassert),\na CBB (Control Backbone) timeout occurs at DBI register offset 0x8bc\n(PCIE_MISC_CONTROL_1_OFF). This happens because pci_epc_deinit_notify()\nand dw_pcie_ep_cleanup() are called before reset_control_deassert() powers\non the controller core.\n\nThe call chain that causes the timeout:\n\n  pex_ep_event_pex_rst_deassert()\n    pci_epc_deinit_notify()\n      pci_epf_test_epc_deinit()\n        pci_epf_test_clear_bar()\n          pci_epc_clear_bar()\n            dw_pcie_ep_clear_bar()\n              __dw_pcie_ep_reset_bar()\n                dw_pcie_dbi_ro_wr_en()      <- Accesses 0x8bc DBI register\n    reset_control_deassert(pcie->core_rst)  <- Core powered on HERE\n\nThe DBI registers, including PCIE_MISC_CONTROL_1_OFF (0x8bc), are only\naccessible after the controller core is powered on via\nreset_control_deassert(pcie->core_rst). Accessing them before this point\nresults in a CBB timeout because the hardware is not yet operational.\n\nFix this by moving pci_epc_deinit_notify() and dw_pcie_ep_cleanup() to\nafter reset_control_deassert(pcie->core_rst), ensuring the controller is\nfully powered on before any DBI register accesses occur.","publishedAt":"2026-06-24T16:29:56.949Z","updatedAt":"2026-06-24T16:29:56.949Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"72034050ccf4202cd6558b0afd2474f756ea3b9b","status":"affected","lessThan":"010983063a806720b45778d191335f8ea864fea3","versionType":"git"},{"version":"40e2125381dc11379112485e3eefdd25c6df5375","status":"affected","lessThan":"b059a41bdd5b202b2b9d7708403fb43c69689e53","versionType":"git"},{"version":"40e2125381dc11379112485e3eefdd25c6df5375","status":"affected","lessThan":"ce899f9c019591b73ef84b9afa332ed53beece25","versionType":"git"},{"version":"40e2125381dc11379112485e3eefdd25c6df5375","status":"affected","lessThan":"34b3eef48d980cd37b876e128bbf314f69fb5d70","versionType":"git"},{"version":"70212c2300971506e986d95000d2745529cac9d7","status":"affected","versionType":"git"},{"version":"6.12.2","status":"affected","lessThan":"6.12.91","versionType":"semver"},{"version":"6.11.11","status":"affected","lessThan":"6.12","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/pci/controller/dwc/pcie-tegra194.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.13","versionType":"semver"},{"version":"6.12.91","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.33","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.10","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/pci/controller/dwc/pcie-tegra194.c"]}],"references":["https://git.kernel.org/stable/c/010983063a806720b45778d191335f8ea864fea3","https://git.kernel.org/stable/c/b059a41bdd5b202b2b9d7708403fb43c69689e53","https://git.kernel.org/stable/c/ce899f9c019591b73ef84b9afa332ed53beece25","https://git.kernel.org/stable/c/34b3eef48d980cd37b876e128bbf314f69fb5d70"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/53xxx/CVE-2026-53051.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-53051","state":"PUBLISHED","datePublished":"2026-06-24T16:29:56.949Z","dateUpdated":"2026-06-24T16:29:56.949Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-06-09T07:44:35.381Z"},"containers":{"cna":{"title":"PCI: tegra194: Fix CBB timeout caused by DBI access before core power-on","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nPCI: tegra194: Fix CBB timeout caused by DBI access before core power-on\n\nWhen PERST# is deasserted twice (assert -> deassert -> assert -> deassert),\na CBB (Control Backbone) timeout occurs at DBI register offset 0x8bc\n(PCIE_MISC_CONTROL_1_OFF). This happens because pci_epc_deinit_notify()\nand dw_pcie_ep_cleanup() are called before reset_control_deassert() powers\non the controller core.\n\nThe call chain that causes the timeout:\n\n  pex_ep_event_pex_rst_deassert()\n    pci_epc_deinit_notify()\n      pci_epf_test_epc_deinit()\n        pci_epf_test_clear_bar()\n          pci_epc_clear_bar()\n            dw_pcie_ep_clear_bar()\n              __dw_pcie_ep_reset_bar()\n                dw_pcie_dbi_ro_wr_en()      <- Accesses 0x8bc DBI register\n    reset_control_deassert(pcie->core_rst)  <- Core powered on HERE\n\nThe DBI registers, including PCIE_MISC_CONTROL_1_OFF (0x8bc), are only\naccessible after the controller core is powered on via\nreset_control_deassert(pcie->core_rst). Accessing them before this point\nresults in a CBB timeout because the hardware is not yet operational.\n\nFix this by moving pci_epc_deinit_notify() and dw_pcie_ep_cleanup() to\nafter reset_control_deassert(pcie->core_rst), ensuring the controller is\nfully powered on before any DBI register accesses occur."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"72034050ccf4202cd6558b0afd2474f756ea3b9b","status":"affected","lessThan":"010983063a806720b45778d191335f8ea864fea3","versionType":"git"},{"version":"40e2125381dc11379112485e3eefdd25c6df5375","status":"affected","lessThan":"b059a41bdd5b202b2b9d7708403fb43c69689e53","versionType":"git"},{"version":"40e2125381dc11379112485e3eefdd25c6df5375","status":"affected","lessThan":"ce899f9c019591b73ef84b9afa332ed53beece25","versionType":"git"},{"version":"40e2125381dc11379112485e3eefdd25c6df5375","status":"affected","lessThan":"34b3eef48d980cd37b876e128bbf314f69fb5d70","versionType":"git"},{"version":"70212c2300971506e986d95000d2745529cac9d7","status":"affected","versionType":"git"},{"version":"6.12.2","status":"affected","lessThan":"6.12.91","versionType":"semver"},{"version":"6.11.11","status":"affected","lessThan":"6.12","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/pci/controller/dwc/pcie-tegra194.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.13","versionType":"semver"},{"version":"6.12.91","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.33","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.10","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/pci/controller/dwc/pcie-tegra194.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/010983063a806720b45778d191335f8ea864fea3"},{"url":"https://git.kernel.org/stable/c/b059a41bdd5b202b2b9d7708403fb43c69689e53"},{"url":"https://git.kernel.org/stable/c/ce899f9c019591b73ef84b9afa332ed53beece25"},{"url":"https://git.kernel.org/stable/c/34b3eef48d980cd37b876e128bbf314f69fb5d70"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-06-24T16:29:56.949Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12.2","versionEndExcluding":"6.12.91"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"6.18.33"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"7.0.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"7.1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11.11"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}