From d47ad4c29f1cd34aff896a88b3dfc4a861a15a6a Mon Sep 17 00:00:00 2001 From: Ralf Ramsauer Date: Thu, 10 Oct 2019 12:21:01 +0200 Subject: [PATCH 01/32] x86/jailhouse: Improve setup data version comparison Soon, setup_data will contain information on passed-through platform UARTs. This requires some preparational work for the sanity check of the header and the check of the version. Use the following strategy: 1. Ensure that the header declares at least enough space for the version and the compatible_version as it must hold that fields for any version. The location and semantics of header+version fields will never change. 2. Copy over data -- as much as as possible. The length is either limited by the header length or the length of setup_data. 3. Things are now in place -- sanity check if the header length complies the actual version. For future versions of the setup_data, only step 3 requires alignment. Signed-off-by: Ralf Ramsauer Signed-off-by: Borislav Petkov Reviewed-by: Jan Kiszka Cc: Baoquan He Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: jailhouse-dev@googlegroups.com Cc: Juergen Gross Cc: "Kirill A. Shutemov" Cc: Thomas Gleixner Cc: x86-ml Link: https://lkml.kernel.org/r/20191010102102.421035-2-ralf.ramsauer@oth-regensburg.de --- arch/x86/include/uapi/asm/bootparam.h | 22 ++++++++------- arch/x86/kernel/jailhouse.c | 51 ++++++++++++++++++++++------------- 2 files changed, 45 insertions(+), 28 deletions(-) diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h index c895df5482c5..43be437c9c71 100644 --- a/arch/x86/include/uapi/asm/bootparam.h +++ b/arch/x86/include/uapi/asm/bootparam.h @@ -139,15 +139,19 @@ struct boot_e820_entry { * setup data structure. */ struct jailhouse_setup_data { - __u16 version; - __u16 compatible_version; - __u16 pm_timer_address; - __u16 num_cpus; - __u64 pci_mmconfig_base; - __u32 tsc_khz; - __u32 apic_khz; - __u8 standard_ioapic; - __u8 cpu_ids[255]; + struct { + __u16 version; + __u16 compatible_version; + } __attribute__((packed)) hdr; + struct { + __u16 pm_timer_address; + __u16 num_cpus; + __u64 pci_mmconfig_base; + __u32 tsc_khz; + __u32 apic_khz; + __u8 standard_ioapic; + __u8 cpu_ids[255]; + } __attribute__((packed)) v1; } __attribute__((packed)); /* The so-called "zeropage" */ diff --git a/arch/x86/kernel/jailhouse.c b/arch/x86/kernel/jailhouse.c index 3ad34f01de2a..cf4eb37ad97b 100644 --- a/arch/x86/kernel/jailhouse.c +++ b/arch/x86/kernel/jailhouse.c @@ -22,6 +22,8 @@ #include static __initdata struct jailhouse_setup_data setup_data; +#define SETUP_DATA_V1_LEN (sizeof(setup_data.hdr) + sizeof(setup_data.v1)) + static unsigned int precalibrated_tsc_khz; static uint32_t jailhouse_cpuid_base(void) @@ -45,7 +47,7 @@ static void jailhouse_get_wallclock(struct timespec64 *now) static void __init jailhouse_timer_init(void) { - lapic_timer_period = setup_data.apic_khz * (1000 / HZ); + lapic_timer_period = setup_data.v1.apic_khz * (1000 / HZ); } static unsigned long jailhouse_get_tsc(void) @@ -88,14 +90,14 @@ static void __init jailhouse_get_smp_config(unsigned int early) register_lapic_address(0xfee00000); - for (cpu = 0; cpu < setup_data.num_cpus; cpu++) { - generic_processor_info(setup_data.cpu_ids[cpu], + for (cpu = 0; cpu < setup_data.v1.num_cpus; cpu++) { + generic_processor_info(setup_data.v1.cpu_ids[cpu], boot_cpu_apic_version); } smp_found_config = 1; - if (setup_data.standard_ioapic) { + if (setup_data.v1.standard_ioapic) { mp_register_ioapic(0, 0xfec00000, gsi_top, &ioapic_cfg); /* Register 1:1 mapping for legacy UART IRQs 3 and 4 */ @@ -126,9 +128,9 @@ static int __init jailhouse_pci_arch_init(void) pcibios_last_bus = 0xff; #ifdef CONFIG_PCI_MMCONFIG - if (setup_data.pci_mmconfig_base) { + if (setup_data.v1.pci_mmconfig_base) { pci_mmconfig_add(0, 0, pcibios_last_bus, - setup_data.pci_mmconfig_base); + setup_data.v1.pci_mmconfig_base); pci_mmcfg_arch_init(); } #endif @@ -139,6 +141,7 @@ static int __init jailhouse_pci_arch_init(void) static void __init jailhouse_init_platform(void) { u64 pa_data = boot_params.hdr.setup_data; + unsigned long setup_data_len; struct setup_data header; void *mapping; @@ -163,16 +166,8 @@ static void __init jailhouse_init_platform(void) memcpy(&header, mapping, sizeof(header)); early_memunmap(mapping, sizeof(header)); - if (header.type == SETUP_JAILHOUSE && - header.len >= sizeof(setup_data)) { - pa_data += offsetof(struct setup_data, data); - - mapping = early_memremap(pa_data, sizeof(setup_data)); - memcpy(&setup_data, mapping, sizeof(setup_data)); - early_memunmap(mapping, sizeof(setup_data)); - + if (header.type == SETUP_JAILHOUSE) break; - } pa_data = header.next; } @@ -180,13 +175,27 @@ static void __init jailhouse_init_platform(void) if (!pa_data) panic("Jailhouse: No valid setup data found"); - if (setup_data.compatible_version > JAILHOUSE_SETUP_REQUIRED_VERSION) - panic("Jailhouse: Unsupported setup data structure"); + /* setup data must at least contain the header */ + if (header.len < sizeof(setup_data.hdr)) + goto unsupported; - pmtmr_ioport = setup_data.pm_timer_address; + pa_data += offsetof(struct setup_data, data); + setup_data_len = min_t(unsigned long, sizeof(setup_data), + (unsigned long)header.len); + mapping = early_memremap(pa_data, setup_data_len); + memcpy(&setup_data, mapping, setup_data_len); + early_memunmap(mapping, setup_data_len); + + if (setup_data.hdr.version == 0 || + setup_data.hdr.compatible_version != + JAILHOUSE_SETUP_REQUIRED_VERSION || + (setup_data.hdr.version >= 1 && header.len < SETUP_DATA_V1_LEN)) + goto unsupported; + + pmtmr_ioport = setup_data.v1.pm_timer_address; pr_debug("Jailhouse: PM-Timer IO Port: %#x\n", pmtmr_ioport); - precalibrated_tsc_khz = setup_data.tsc_khz; + precalibrated_tsc_khz = setup_data.v1.tsc_khz; setup_force_cpu_cap(X86_FEATURE_TSC_KNOWN_FREQ); pci_probe = 0; @@ -196,6 +205,10 @@ static void __init jailhouse_init_platform(void) * are none in a non-root cell. */ disable_acpi(); + return; + +unsupported: + panic("Jailhouse: Unsupported setup data structure"); } bool jailhouse_paravirt(void) -- 2.11.0