[tip: x86/microcode] x86/microcode/intel: Reuse microcode_sanity_check()

tip-bot2 for Jithu Joseph
2022-11-19T16:24:50Z

The following commit has been merged into the x86/microcode branch of tip:

Commit-ID: 514ee839c6d0750c1c4456502e6fa08599e57931
Gitweb: https://git.kernel.org/tip/514ee839c6d0750c1c4456502e6fa08599e57931
Author: Jithu Joseph <jithu.joseph@intel.com>
AuthorDate: Wed, 16 Nov 2022 19:59:26 -08:00
Committer: Borislav Petkov <bp@suse.de>
CommitterDate: Fri, 18 Nov 2022 22:00:17 +01:00

x86/microcode/intel: Reuse microcode_sanity_check()

IFS test image carries the same microcode header as regular Intel
microcode blobs.

Reuse microcode_sanity_check() in the IFS driver to perform sanity check
of the IFS test images too.

Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Link: https://lore.kernel.org/r/20221117035935.4136738-8-jithu.joseph@intel.com
---
arch/x86/include/asm/cpu.h | 1 +-
arch/x86/kernel/cpu/intel.c | 99 ++++++++++++++++++++++++-
arch/x86/kernel/cpu/microcode/intel.c | 102 +-------------------------
3 files changed, 102 insertions(+), 100 deletions(-)

diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index e853440..9e3ac95 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -96,5 +96,6 @@ static inline bool intel_cpu_signatures_match(unsigned int s1, unsigned int p1,

extern u64 x86_read_arch_cap_msr(void);
int intel_find_matching_signature(void *mc, unsigned int csig, int cpf);
+int intel_microcode_sanity_check(void *mc, bool print_err);

#endif /* _ASM_X86_CPU_H */
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index c7331ec..bef06a1 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -244,6 +244,105 @@ int intel_find_matching_signature(void *mc, unsigned int csig, int cpf)
}
EXPORT_SYMBOL_GPL(intel_find_matching_signature);

+int intel_microcode_sanity_check(void *mc, bool print_err)
+{
+ unsigned long total_size, data_size, ext_table_size;
+ struct microcode_header_intel *mc_header = mc;
+ struct extended_sigtable *ext_header = NULL;
+ u32 sum, orig_sum, ext_sigcount = 0, i;
+ struct extended_signature *ext_sig;
+
+ total_size = get_totalsize(mc_header);
+ data_size = get_datasize(mc_header);
+
+ if (data_size + MC_HEADER_SIZE > total_size) {
+ if (print_err)
+ pr_err("Error: bad microcode data file size.\n");
+ return -EINVAL;
+ }
+
+ if (mc_header->ldrver != 1 || mc_header->hdrver != 1) {
+ if (print_err)
+ pr_err("Error: invalid/unknown microcode update format.\n");
+ return -EINVAL;
+ }
+
+ ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
+ if (ext_table_size) {
+ u32 ext_table_sum = 0;
+ u32 *ext_tablep;
+
+ if (ext_table_size < EXT_HEADER_SIZE ||
+ ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
+ if (print_err)
+ pr_err("Error: truncated extended signature table.\n");
+ return -EINVAL;
+ }
+
+ ext_header = mc + MC_HEADER_SIZE + data_size;
+ if (ext_table_size != exttable_size(ext_header)) {
+ if (print_err)
+ pr_err("Error: extended signature table size mismatch.\n");
+ return -EFAULT;
+ }
+
+ ext_sigcount = ext_header->count;
+
+ /*
+ * Check extended table checksum: the sum of all dwords that
+ * comprise a valid table must be 0.
+ */
+ ext_tablep = (u32 *)ext_header;
+
+ i = ext_table_size / sizeof(u32);
+ while (i--)
+ ext_table_sum += ext_tablep[i];
+
+ if (ext_table_sum) {
+ if (print_err)
+ pr_warn("Bad extended signature table checksum, aborting.\n");
+ return -EINVAL;
+ }
+ }
+
+ /*
+ * Calculate the checksum of update data and header. The checksum of
+ * valid update data and header including the extended signature table
+ * must be 0.
+ */
+ orig_sum = 0;
+ i = (MC_HEADER_SIZE + data_size) / sizeof(u32);
+ while (i--)
+ orig_sum += ((u32 *)mc)[i];
+
+ if (orig_sum) {
+ if (print_err)
+ pr_err("Bad microcode data checksum, aborting.\n");
+ return -EINVAL;
+ }
+
+ if (!ext_table_size)
+ return 0;
+
+ /*
+ * Check extended signature checksum: 0 => valid.
+ */
+ for (i = 0; i < ext_sigcount; i++) {
+ ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
+ EXT_SIGNATURE_SIZE * i;
+
+ sum = (mc_header->sig + mc_header->pf + mc_header->cksum) -
+ (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
+ if (sum) {
+ if (print_err)
+ pr_err("Bad extended signature checksum, aborting.\n");
+ return -EINVAL;
+ }
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(intel_microcode_sanity_check);
+
static void early_init_intel(struct cpuinfo_x86 *c)
{
u64 misc_enable;
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index e48f05e..fb6ff71 100644
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -135,104 +135,6 @@ static void save_microcode_patch(struct ucode_cpu_info *uci, void *data, unsigne
intel_ucode_patch = p->data;
}

-static int microcode_sanity_check(void *mc, bool print_err)
-{
- unsigned long total_size, data_size, ext_table_size;
- struct microcode_header_intel *mc_header = mc;
- struct extended_sigtable *ext_header = NULL;
- u32 sum, orig_sum, ext_sigcount = 0, i;
- struct extended_signature *ext_sig;
-
- total_size = get_totalsize(mc_header);
- data_size = get_datasize(mc_header);
-
- if (data_size + MC_HEADER_SIZE > total_size) {
- if (print_err)
- pr_err("Error: bad microcode data file size.\n");
- return -EINVAL;
- }
-
- if (mc_header->ldrver != 1 || mc_header->hdrver != 1) {
- if (print_err)
- pr_err("Error: invalid/unknown microcode update format.\n");
- return -EINVAL;
- }
-
- ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
- if (ext_table_size) {
- u32 ext_table_sum = 0;
- u32 *ext_tablep;
-
- if ((ext_table_size < EXT_HEADER_SIZE)
- || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
- if (print_err)
- pr_err("Error: truncated extended signature table.\n");
- return -EINVAL;
- }
-
- ext_header = mc + MC_HEADER_SIZE + data_size;
- if (ext_table_size != exttable_size(ext_header)) {
- if (print_err)
- pr_err("Error: extended signature table size mismatch.\n");
- return -EFAULT;
- }
-
- ext_sigcount = ext_header->count;
-
- /*
- * Check extended table checksum: the sum of all dwords that
- * comprise a valid table must be 0.
- */
- ext_tablep = (u32 *)ext_header;
-
- i = ext_table_size / sizeof(u32);
- while (i--)
- ext_table_sum += ext_tablep[i];
-
- if (ext_table_sum) {
- if (print_err)
- pr_warn("Bad extended signature table checksum, aborting.\n");
- return -EINVAL;
- }
- }
-
- /*
- * Calculate the checksum of update data and header. The checksum of
- * valid update data and header including the extended signature table
- * must be 0.
- */
- orig_sum = 0;
- i = (MC_HEADER_SIZE + data_size) / sizeof(u32);
- while (i--)
- orig_sum += ((u32 *)mc)[i];
-
- if (orig_sum) {
- if (print_err)
- pr_err("Bad microcode data checksum, aborting.\n");
- return -EINVAL;
- }
-
- if (!ext_table_size)
- return 0;
-
- /*
- * Check extended signature checksum: 0 => valid.
- */
- for (i = 0; i < ext_sigcount; i++) {
- ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
- EXT_SIGNATURE_SIZE * i;
-
- sum = (mc_header->sig + mc_header->pf + mc_header->cksum) -
- (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
- if (sum) {
- if (print_err)
- pr_err("Bad extended signature checksum, aborting.\n");
- return -EINVAL;
- }
- }
- return 0;
-}
-
/*
* Get microcode matching with BSP's model. Only CPUs with the same model as
* BSP can stay in the platform.
@@ -253,7 +155,7 @@ scan_microcode(void *data, size_t size, struct ucode_cpu_info *uci, bool save)
mc_size = get_totalsize(mc_header);
if (!mc_size ||
mc_size > size ||
- microcode_sanity_check(data, false) < 0)
+ intel_microcode_sanity_check(data, false) < 0)
break;

size -= mc_size;
@@ -792,7 +694,7 @@ static enum ucode_state generic_load_microcode(int cpu, struct iov_iter *iter)
memcpy(mc, &mc_header, sizeof(mc_header));
data = mc + sizeof(mc_header);
if (!copy_from_iter_full(data, data_size, iter) ||
- microcode_sanity_check(mc, true) < 0) {
+ intel_microcode_sanity_check(mc, true) < 0) {
break;
}