From 40b7f3dfcc5ab211a0b8d916751bb22ac2290806 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Wed, 15 Jun 2011 15:34:57 +0200 Subject: [PATCH] x86, microcode, AMD: Fix section header size check The ucode size check has to take the section header size into account too when sanity checking the section length. Shorten and clarify define names, while at it. Caught-by: Ben Hutchings Link: http://lkml.kernel.org/r/1302752223.5282.674.camel@localhost Signed-off-by: Borislav Petkov --- arch/x86/kernel/microcode_amd.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c index d30d67cd33ad..591be0ee1934 100644 --- a/arch/x86/kernel/microcode_amd.c +++ b/arch/x86/kernel/microcode_amd.c @@ -66,8 +66,8 @@ struct microcode_amd { unsigned int mpb[0]; }; -#define UCODE_CONTAINER_SECTION_HDR 8 -#define UCODE_CONTAINER_HEADER_SIZE 12 +#define SECTION_HDR_SIZE 8 +#define CONTAINER_HDR_SZ 12 static struct equiv_cpu_entry *equiv_cpu_table; @@ -177,7 +177,7 @@ static unsigned int verify_ucode_size(int cpu, const u8 *buf, unsigned int size) actual_size = *(u32 *)(buf + 4); - if (actual_size > size || actual_size > max_size) { + if (actual_size + SECTION_HDR_SIZE > size || actual_size > max_size) { pr_err("section size mismatch\n"); return 0; } @@ -204,8 +204,8 @@ get_next_ucode(int cpu, const u8 *buf, unsigned int size, unsigned int *mc_size) if (!mc) goto out; - get_ucode_data(mc, buf + UCODE_CONTAINER_SECTION_HDR, actual_size); - *mc_size = actual_size + UCODE_CONTAINER_SECTION_HDR; + get_ucode_data(mc, buf + SECTION_HDR_SIZE, actual_size); + *mc_size = actual_size + SECTION_HDR_SIZE; out: return mc; @@ -229,9 +229,10 @@ static int install_equiv_cpu_table(const u8 *buf) return -ENOMEM; } - get_ucode_data(equiv_cpu_table, buf + UCODE_CONTAINER_HEADER_SIZE, size); + get_ucode_data(equiv_cpu_table, buf + CONTAINER_HDR_SZ, size); - return size + UCODE_CONTAINER_HEADER_SIZE; /* add header length */ + /* add header length */ + return size + CONTAINER_HDR_SZ; } static void free_equiv_cpu_table(void) -- 2.39.2