[PATCH v6 6/8] x86/microcode/AMD: Integrate verify_patch_size() into verify_patch()

From: Maciej S. Szmigiero
Date: Sat May 19 2018 - 17:13:06 EST


Now that the previous commit converted the late loader to do a full patch
checking via verify_patch() instead of calling verify_patch_size() directly
we can integrate the later function into the former because it was its only
user.

Signed-off-by: Maciej S. Szmigiero <mail@xxxxxxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/cpu/microcode/amd.c | 72 +++++++++++------------------
1 file changed, 27 insertions(+), 45 deletions(-)

diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index 3e10a5920f58..764dac82c03f 100644
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -182,9 +182,6 @@ static bool verify_patch_section(const u8 *buf, size_t buf_size, bool early)
return true;
}

-static unsigned int verify_patch_size(u8 family, u32 patch_size,
- unsigned int size);
-
/*
* Checks whether a microcode patch located at the beginning of a passed
* buffer @buf of size @size is not too large for a particular @family
@@ -195,19 +192,43 @@ static unsigned int verify_patch_size(u8 family, u32 patch_size,
static bool verify_patch(u8 family, const u8 *buf, size_t buf_size, bool early)
{
const u32 *hdr = (const u32 *)buf;
- u32 patch_size;
+ u32 patch_size, max_size;

if (!verify_patch_section(buf, buf_size, early))
return false;

patch_size = hdr[1];

+#define F1XH_MPB_MAX_SIZE 2048
+#define F14H_MPB_MAX_SIZE 1824
+#define F15H_MPB_MAX_SIZE 4096
+#define F16H_MPB_MAX_SIZE 3458
+#define F17H_MPB_MAX_SIZE 3200
+
+ switch (family) {
+ case 0x14:
+ max_size = F14H_MPB_MAX_SIZE;
+ break;
+ case 0x15:
+ max_size = F15H_MPB_MAX_SIZE;
+ break;
+ case 0x16:
+ max_size = F16H_MPB_MAX_SIZE;
+ break;
+ case 0x17:
+ max_size = F17H_MPB_MAX_SIZE;
+ break;
+ default:
+ max_size = F1XH_MPB_MAX_SIZE;
+ break;
+ }
+
/*
* The section header length is not included in this indicated size
* but is present in the leftover file length so we need to subtract
- * it before passing this value to the function below.
+ * it from the leftover file length.
*/
- if (!verify_patch_size(family, patch_size, buf_size - SECTION_HDR_SIZE)) {
+ if (patch_size > min_t(u32, max_size, buf_size - SECTION_HDR_SIZE)) {
if (!early)
pr_err("Patch of size %u too large.\n", patch_size);

@@ -612,45 +633,6 @@ static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
return 0;
}

-/*
- * Check whether the passed remaining file @size is large enough to contain a
- * patch of the indicated @patch_size (and also whether this size does not
- * exceed the per-family maximum).
- */
-static unsigned int verify_patch_size(u8 family, u32 patch_size, unsigned int size)
-{
- u32 max_size;
-
-#define F1XH_MPB_MAX_SIZE 2048
-#define F14H_MPB_MAX_SIZE 1824
-#define F15H_MPB_MAX_SIZE 4096
-#define F16H_MPB_MAX_SIZE 3458
-#define F17H_MPB_MAX_SIZE 3200
-
- switch (family) {
- case 0x14:
- max_size = F14H_MPB_MAX_SIZE;
- break;
- case 0x15:
- max_size = F15H_MPB_MAX_SIZE;
- break;
- case 0x16:
- max_size = F16H_MPB_MAX_SIZE;
- break;
- case 0x17:
- max_size = F17H_MPB_MAX_SIZE;
- break;
- default:
- max_size = F1XH_MPB_MAX_SIZE;
- break;
- }
-
- if (patch_size > min_t(u32, size, max_size))
- return 0;
-
- return patch_size;
-}
-
static enum ucode_state apply_microcode_amd(int cpu)
{
struct cpuinfo_x86 *c = &cpu_data(cpu);