lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Fri, 28 Jan 2022 11:17:46 -0600
From:   Brijesh Singh <brijesh.singh@....com>
To:     <x86@...nel.org>, <linux-kernel@...r.kernel.org>,
        <kvm@...r.kernel.org>, <linux-efi@...r.kernel.org>,
        <platform-driver-x86@...r.kernel.org>,
        <linux-coco@...ts.linux.dev>, <linux-mm@...ck.org>
CC:     Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Joerg Roedel <jroedel@...e.de>,
        Tom Lendacky <thomas.lendacky@....com>,
        "H. Peter Anvin" <hpa@...or.com>, Ard Biesheuvel <ardb@...nel.org>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Sean Christopherson <seanjc@...gle.com>,
        "Vitaly Kuznetsov" <vkuznets@...hat.com>,
        Jim Mattson <jmattson@...gle.com>,
        "Andy Lutomirski" <luto@...nel.org>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        Sergio Lopez <slp@...hat.com>, Peter Gonda <pgonda@...gle.com>,
        "Peter Zijlstra" <peterz@...radead.org>,
        Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
        David Rientjes <rientjes@...gle.com>,
        Dov Murik <dovmurik@...ux.ibm.com>,
        Tobin Feldman-Fitzthum <tobin@....com>,
        Borislav Petkov <bp@...en8.de>,
        Michael Roth <michael.roth@....com>,
        Vlastimil Babka <vbabka@...e.cz>,
        "Kirill A . Shutemov" <kirill@...temov.name>,
        Andi Kleen <ak@...ux.intel.com>,
        "Dr . David Alan Gilbert" <dgilbert@...hat.com>,
        <brijesh.ksingh@...il.com>, <tony.luck@...el.com>,
        <marcorr@...gle.com>, <sathyanarayanan.kuppuswamy@...ux.intel.com>,
        Brijesh Singh <brijesh.singh@....com>
Subject: [PATCH v9 25/43] x86/compressed/acpi: Move EFI system table lookup to helper

From: Michael Roth <michael.roth@....com>

Future patches for SEV-SNP-validated CPUID will also require early
parsing of the EFI configuration. Incrementally move the related
code into a set of helpers that can be re-used for that purpose.

Signed-off-by: Michael Roth <michael.roth@....com>
Signed-off-by: Brijesh Singh <brijesh.singh@....com>
---
 arch/x86/boot/compressed/acpi.c | 21 +++++++--------------
 arch/x86/boot/compressed/efi.c  | 29 +++++++++++++++++++++++++++++
 arch/x86/boot/compressed/misc.h |  6 ++++++
 3 files changed, 42 insertions(+), 14 deletions(-)

diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c
index db6c561920f0..58a3d3f3e305 100644
--- a/arch/x86/boot/compressed/acpi.c
+++ b/arch/x86/boot/compressed/acpi.c
@@ -105,7 +105,7 @@ static acpi_physical_address kexec_get_rsdp_addr(void)
 	}
 
 	/* Get systab from boot params. */
-	systab = (efi_system_table_64_t *) (ei->efi_systab | ((__u64)ei->efi_systab_hi << 32));
+	systab = (efi_system_table_64_t *)efi_get_system_table(boot_params);
 	if (!systab)
 		error("EFI system table not found in kexec boot_params.");
 
@@ -118,9 +118,8 @@ static acpi_physical_address kexec_get_rsdp_addr(void) { return 0; }
 static acpi_physical_address efi_get_rsdp_addr(void)
 {
 #ifdef CONFIG_EFI
-	unsigned long systab, config_tables;
+	unsigned long systab_pa, config_tables;
 	unsigned int nr_tables;
-	struct efi_info *ei;
 	enum efi_type et;
 	bool efi_64;
 
@@ -132,24 +131,18 @@ static acpi_physical_address efi_get_rsdp_addr(void)
 	else
 		return 0;
 
-	/* Get systab from boot params. */
-	ei = &boot_params->efi_info;
-#ifdef CONFIG_X86_64
-	systab = ei->efi_systab | ((__u64)ei->efi_systab_hi << 32);
-#else
-	systab = ei->efi_systab;
-#endif
-	if (!systab)
-		error("EFI system table not found.");
+	systab_pa = efi_get_system_table(boot_params);
+	if (!systab_pa)
+		error("EFI support advertised, but unable to locate system table.");
 
 	/* Handle EFI bitness properly */
 	if (efi_64) {
-		efi_system_table_64_t *stbl = (efi_system_table_64_t *)systab;
+		efi_system_table_64_t *stbl = (efi_system_table_64_t *)systab_pa;
 
 		config_tables	= stbl->tables;
 		nr_tables	= stbl->nr_tables;
 	} else {
-		efi_system_table_32_t *stbl = (efi_system_table_32_t *)systab;
+		efi_system_table_32_t *stbl = (efi_system_table_32_t *)systab_pa;
 
 		config_tables	= stbl->tables;
 		nr_tables	= stbl->nr_tables;
diff --git a/arch/x86/boot/compressed/efi.c b/arch/x86/boot/compressed/efi.c
index daa73efdc7a5..bf99768cd229 100644
--- a/arch/x86/boot/compressed/efi.c
+++ b/arch/x86/boot/compressed/efi.c
@@ -48,3 +48,32 @@ enum efi_type efi_get_type(struct boot_params *boot_params)
 
 	return et;
 }
+
+/*
+ * efi_get_system_table - Given boot_params, retrieve the physical address of
+ *                        EFI system table.
+ *
+ * @boot_params:        pointer to boot_params
+ *
+ * Return: EFI system table address on success. On error, return 0.
+ */
+unsigned long efi_get_system_table(struct boot_params *boot_params)
+{
+	unsigned long sys_tbl_pa;
+	struct efi_info *ei;
+	enum efi_type et;
+
+	/* Get systab from boot params. */
+	ei = &boot_params->efi_info;
+#ifdef CONFIG_X86_64
+	sys_tbl_pa = ei->efi_systab | ((__u64)ei->efi_systab_hi << 32);
+#else
+	sys_tbl_pa = ei->efi_systab;
+#endif
+	if (!sys_tbl_pa) {
+		debug_putstr("EFI system table not found.");
+		return 0;
+	}
+
+	return sys_tbl_pa;
+}
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index a26244c0fe01..24522be8c21d 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -185,11 +185,17 @@ enum efi_type {
 #ifdef CONFIG_EFI
 /* helpers for early EFI config table access */
 enum efi_type efi_get_type(struct boot_params *boot_params);
+unsigned long efi_get_system_table(struct boot_params *boot_params);
 #else
 static inline enum efi_type efi_get_type(struct boot_params *boot_params)
 {
 	return EFI_TYPE_NONE;
 }
+
+static inline unsigned long efi_get_system_table(struct boot_params *boot_params)
+{
+	return 0;
+}
 #endif /* CONFIG_EFI */
 
 #endif /* BOOT_COMPRESSED_MISC_H */
-- 
2.25.1

Powered by blists - more mailing lists