x86/microcode/AMD: Sanitize apply_microcode_early_amd()

Make it simply return bool to denote whether it found a container or not
and return the pointer to the container and its size in the handed-in
container pointer instead, as returning a struct was just silly.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Jürgen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: http://lkml.kernel.org/r/20161218164414.9649-3-bp@alien8.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index 31f4e3f94d46c01688017f543a3b7164c6bb40ca..dc80acfa922d43e365b56ce3643711bb7eb96c4d 100644 (file)
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -216,17 +216,18 @@ static int __apply_microcode_amd(struct microcode_amd *mc_amd)
  * and on 32-bit during save_microcode_in_initrd_amd() -- we can call
  * load_microcode_amd() to save equivalent cpu table and microcode patches in
  * kernel heap memory.
+ *
+ * Returns true if container found (sets @ret_cont), false otherwise.
  */
-static struct container
-apply_microcode_early_amd(void *ucode, size_t size, bool save_patch)
+static bool apply_microcode_early_amd(void *ucode, size_t size, bool save_patch,
+                                     struct container *ret_cont)
 {
-       struct container ret = { NULL, 0 };
        u8 (*patch)[PATCH_MAX_SIZE];
+       u32 rev, *header, *new_rev;
+       struct container ret;
        int offset, left;
-       u32 rev, *header;
-       u8  *data;
        u16 eq_id = 0;
-       u32 *new_rev;
+       u8  *data;
 
 #ifdef CONFIG_X86_32
        new_rev = (u32 *)__pa_nodebug(&ucode_new_rev);
@@ -237,11 +238,11 @@ apply_microcode_early_amd(void *ucode, size_t size, bool save_patch)
 #endif
 
        if (check_current_patch_level(&rev, true))
-               return (struct container){ NULL, 0 };
+               return false;
 
        eq_id = find_proper_container(ucode, size, &ret);
        if (!eq_id)
-               return (struct container){ NULL, 0 };
+               return false;
 
        this_equiv_id = eq_id;
        header = (u32 *)ret.data;
@@ -275,7 +276,11 @@ apply_microcode_early_amd(void *ucode, size_t size, bool save_patch)
                data   += offset;
                left   -= offset;
        }
-       return ret;
+
+       if (ret_cont)
+               *ret_cont = ret;
+
+       return true;
 }
 
 static bool get_builtin_microcode(struct cpio_data *cp, unsigned int family)
@@ -319,7 +324,7 @@ void __init load_ucode_amd_bsp(unsigned int family)
        /* Get BSP's CPUID.EAX(1), needed in load_microcode_amd() */
        uci->cpu_sig.sig = cpuid_eax(1);
 
-       apply_microcode_early_amd(cp.data, cp.size, true);
+       apply_microcode_early_amd(cp.data, cp.size, true, NULL);
 }
 
 #ifdef CONFIG_X86_32
@@ -351,7 +356,7 @@ void load_ucode_amd_ap(unsigned int family)
         * This would set amd_ucode_patch above so that the following APs can
         * use it directly instead of going down this path again.
         */
-       apply_microcode_early_amd(cp.data, cp.size, true);
+       apply_microcode_early_amd(cp.data, cp.size, true, NULL);
 }
 #else
 void load_ucode_amd_ap(unsigned int family)
@@ -389,8 +394,7 @@ reget:
                        }
                }
 
-               cont = apply_microcode_early_amd(cp.data, cp.size, false);
-               if (!(cont.data && cont.size)) {
+               if (!apply_microcode_early_amd(cp.data, cp.size, false, &cont)) {
                        cont.size = -1;
                        return;
                }