From: Kevin Tian <kevin.tian@intel.com> stable inclusion from stable-v6.6.157 commit 579eb867d3da63f3b5e32f235925e1daa7ec70d0 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/18838 CVE: CVE-2026-89448 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 607432b2618b61df81134be0ef2562b8300c1216 upstream. Currently the conditions of requesting ACS in detect_intel_iommu() don't include tboot, leading to a possible misconfiguration with ACS disabled (e.g. due to user opts) while iommu is later forced on by tboot_force_iommu(). Fix it by checking tboot in detect_intel_iommu(). Fixes: 5d990b627537 ("PCI: add pci_request_acs") Cc: stable@vger.kernel.org Signed-off-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Jiacheng Yu <yujiacheng3@huawei.com> --- drivers/iommu/intel/dmar.c | 15 +++++++++++++-- drivers/iommu/intel/iommu.c | 2 +- drivers/iommu/intel/iommu.h | 2 ++ 3 files changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c index 3a99de229370..5e3a36f24791 100644 --- a/drivers/iommu/intel/dmar.c +++ b/drivers/iommu/intel/dmar.c @@ -972,6 +972,18 @@ dmar_validate_one_drhd(struct acpi_dmar_header *entry, void *arg) return 0; } +static bool dmar_required(void) +{ + /* tboot supersedes any user/platform opt */ + if (!intel_iommu_tboot_noforce && tboot_enabled()) + return true; + + if (!no_iommu && (!dmar_disabled || dmar_platform_optin())) + return true; + + return false; +} + void __init detect_intel_iommu(void) { int ret; @@ -985,8 +997,7 @@ void __init detect_intel_iommu(void) if (!ret) ret = dmar_walk_dmar_table((struct acpi_table_dmar *)dmar_tbl, &validate_drhd_cb); - if (!ret && !no_iommu && !iommu_detected && - (!dmar_disabled || dmar_platform_optin())) { + if (!ret && !iommu_detected && dmar_required()) { iommu_detected = 1; /* Make sure ACS will be enabled */ pci_request_acs(); diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index f982327f3dfd..1f6394d780ee 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -68,7 +68,7 @@ static int rwbf_quirk; * (used when kernel is launched w/ TXT) */ static int force_on = 0; -static int intel_iommu_tboot_noforce; +int intel_iommu_tboot_noforce; static int no_platform_optin; #define ROOT_ENTRY_NR (VTD_PAGE_SIZE/sizeof(struct root_entry)) diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h index 791326fa95ba..afd473a8983d 100644 --- a/drivers/iommu/intel/iommu.h +++ b/drivers/iommu/intel/iommu.h @@ -1172,6 +1172,7 @@ static inline bool ecmd_has_pmu_essential(struct intel_iommu *iommu) extern int dmar_disabled; extern int intel_iommu_enabled; +extern int intel_iommu_tboot_noforce; #else static inline int iommu_calculate_agaw(struct intel_iommu *iommu) { @@ -1184,6 +1185,7 @@ static inline int iommu_calculate_max_sagaw(struct intel_iommu *iommu) #define dmar_disabled (1) #define intel_iommu_enabled (0) #define intel_iommu_sm (0) +#define intel_iommu_tboot_noforce (0) #endif static inline const char *decode_prq_descriptor(char *str, size_t size, -- 2.34.1