openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

x86/microcode/AMD: Convert early parser to the new verification routines 

Now that they have the required functionality, use them to verify the
equivalence table and each patch, thus making parse_container() more
readable.

Originally-by: "Maciej S. Szmigiero" <mail@maciej.szmigiero.name>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: x86@kernel.org
Link: https://lkml.kernel.org/r/20181107170218.7596-12-bp@alien8.de
This commit is contained in:
Borislav Petkov 2018-09-12 18:33:34 +02:00
parent d430a305b7
commit c45e80358c
1 changed files with 24 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

46
arch/x86/kernel/cpu/microcode/amd.c
View File

@ -293,17 +293,18 @@ static ssize_t parse_container(u8 *ucode, ssize_t size, struct cont_desc *desc)
u16 eq_id;
u8 *buf;
/* Am I looking at an equivalence table header? */
if (hdr[0] != UCODE_MAGIC ||
hdr[1] != UCODE_EQUIV_CPU_TABLE_TYPE ||
hdr[2] == 0)
return CONTAINER_HDR_SZ;
if (!verify_equivalence_table(ucode, size, true))
return 0;
buf = ucode;
eq = (struct equiv_cpu_entry *)(buf + CONTAINER_HDR_SZ);
/* Find the equivalence ID of our CPU in this table: */
/*
* Find the equivalence ID of our CPU in this table. Even if this table
* doesn't contain a patch for the CPU, scan through the whole container
* so that it can be skipped in case there are other containers appended.
*/
eq_id = find_equiv_id(eq, desc->cpuid_1_eax);
buf += hdr[2] + CONTAINER_HDR_SZ;
@ -316,29 +317,29 @@ static ssize_t parse_container(u8 *ucode, ssize_t size, struct cont_desc *desc)
while (size > 0) {
struct microcode_amd *mc;
u32 patch_size;
int ret;
hdr = (u32 *)buf;
ret = verify_patch(x86_family(desc->cpuid_1_eax), buf, size, &patch_size, true);
if (ret < 0) {
/*
* Patch verification failed, skip to the next
* container, if there's one:
*/
goto out;
} else if (ret > 0) {
goto skip;
}
if (hdr[0] != UCODE_UCODE_TYPE)
break;
/* Sanity-check patch size. */
patch_size = hdr[1];
if (patch_size > PATCH_MAX_SIZE)
break;
/* Skip patch section header: */
buf += SECTION_HDR_SIZE;
size -= SECTION_HDR_SIZE;
mc = (struct microcode_amd *)buf;
mc = (struct microcode_amd *)(buf + SECTION_HDR_SIZE);
if (eq_id == mc->hdr.processor_rev_id) {
desc->psize = patch_size;
desc->mc = mc;
}
buf += patch_size;
size -= patch_size;
skip:
/* Skip patch section header too: */
buf += patch_size + SECTION_HDR_SIZE;
size -= patch_size + SECTION_HDR_SIZE;
}
/*
@ -355,6 +356,7 @@ static ssize_t parse_container(u8 *ucode, ssize_t size, struct cont_desc *desc)
return 0;
}
out:
return orig_size - size;
}