From 70887cb23eda6bedac73eef227b55e3eb74e0cb7 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Thu, 18 Oct 2018 17:55:45 +0200 Subject: [PATCH] x86/microcode/AMD: Cleanup verify_patch_size() more Rename the variable which contains the patch size read out from the section header to sh_psize for better differentiation of all the "sizes" in that function. Also, improve the comment above it. No functional changes. Signed-off-by: Borislav Petkov Cc: x86@kernel.org Link: https://lkml.kernel.org/r/20181107170218.7596-6-bp@alien8.de --- arch/x86/kernel/cpu/microcode/amd.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c index bf682de..a94a15a 100644 --- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -175,16 +175,18 @@ static bool verify_patch_section(const u8 *buf, size_t buf_size, bool early) } /* - * 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). + * Check whether the passed remaining file @buf_size is large enough to contain + * a patch of the indicated @sh_psize (and also whether this size does not + * exceed the per-family maximum). @sh_psize is the size read from the section + * header. */ -static unsigned int verify_patch_size(u8 family, u32 patch_size, unsigned int size) +static unsigned int +verify_patch_size(u8 family, u32 sh_psize, unsigned int buf_size) { u32 max_size; if (family >= 0x15) - return min_t(u32, patch_size, size); + return min_t(u32, sh_psize, buf_size); #define F1XH_MPB_MAX_SIZE 2048 #define F14H_MPB_MAX_SIZE 1824 @@ -202,12 +204,12 @@ static unsigned int verify_patch_size(u8 family, u32 patch_size, unsigned int si break; } - if (patch_size > min_t(u32, size, max_size)) { + if (sh_psize > min_t(u32, buf_size, max_size)) { pr_err("patch size mismatch\n"); return 0; } - return patch_size; + return sh_psize; } /* @@ -693,14 +695,14 @@ static void cleanup(void) */ static int verify_and_add_patch(u8 family, u8 *fw, unsigned int leftover) { + unsigned int sh_psize, crnt_size, ret; struct microcode_header_amd *mc_hdr; struct ucode_patch *patch; - unsigned int patch_size, crnt_size, ret; u32 proc_fam; u16 proc_id; - patch_size = *(u32 *)(fw + 4); - crnt_size = patch_size + SECTION_HDR_SIZE; + sh_psize = *(u32 *)(fw + 4); + crnt_size = sh_psize + SECTION_HDR_SIZE; mc_hdr = (struct microcode_header_amd *)(fw + SECTION_HDR_SIZE); proc_id = mc_hdr->processor_rev_id; @@ -726,7 +728,7 @@ static int verify_and_add_patch(u8 family, u8 *fw, unsigned int leftover) * but is present in the leftover file length so we need to subtract * it before passing this value to the function below. */ - ret = verify_patch_size(family, patch_size, leftover - SECTION_HDR_SIZE); + ret = verify_patch_size(family, sh_psize, leftover - SECTION_HDR_SIZE); if (!ret) { pr_err("Patch-ID 0x%08x: size mismatch.\n", mc_hdr->patch_id); return crnt_size; @@ -738,7 +740,7 @@ static int verify_and_add_patch(u8 family, u8 *fw, unsigned int leftover) return -EINVAL; } - patch->data = kmemdup(fw + SECTION_HDR_SIZE, patch_size, GFP_KERNEL); + patch->data = kmemdup(fw + SECTION_HDR_SIZE, sh_psize, GFP_KERNEL); if (!patch->data) { pr_err("Patch data allocation failure.\n"); kfree(patch); -- 2.7.4