From 4d9ba7b2188083a09d1b1a1bda7054cc3eb77f67 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Mon, 15 Dec 2014 09:16:09 +0000 Subject: [PATCH] x86/AMD-ucode: correct multiple container handling Avoid emitting an error message referring to an incorrect or corrupt container file just because no entry was found for the running CPU. Additionally switch the order of data validation and consumption in cpu_request_microcode()'s first loop, and also check the types of skipped blocks in container_fast_forward(). Signed-off-by: Jan Beulich Reviewed-by: Andrew Cooper Reviewed-by: Aravind Gopalakrishnan Release-Acked-by: Konrad Rzeszutek Wilk Signed-off-by: Konrad Rzeszutek Wilk --- xen/arch/x86/microcode_amd.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/xen/arch/x86/microcode_amd.c b/xen/arch/x86/microcode_amd.c index b68cf93731..f79b397e34 100644 --- a/xen/arch/x86/microcode_amd.c +++ b/xen/arch/x86/microcode_amd.c @@ -331,12 +331,17 @@ static int container_fast_forward(const void *data, size_t size_left, size_t *of header[1] == UCODE_EQUIV_CPU_TABLE_TYPE ) break; + if ( header[0] != UCODE_UCODE_TYPE ) + return -EINVAL; size = header[1] + SECTION_HDR_SIZE; if ( size < PATCH_HDR_SIZE || size_left < size ) return -EINVAL; size_left -= size; *offset += size; + + if ( !size_left ) + return -ENODATA; } return 0; @@ -386,10 +391,6 @@ static int cpu_request_microcode(int cpu, const void *buf, size_t bufsize) break; } - if ( find_equiv_cpu_id(mc_amd->equiv_cpu_table, current_cpu_id, - &equiv_cpu_id) ) - break; - /* * Could happen as we advance 'offset' early * in install_equiv_cpu_table @@ -401,7 +402,16 @@ static int cpu_request_microcode(int cpu, const void *buf, size_t bufsize) break; } + if ( find_equiv_cpu_id(mc_amd->equiv_cpu_table, current_cpu_id, + &equiv_cpu_id) ) + break; + error = container_fast_forward(buf, bufsize - offset, &offset); + if ( error == -ENODATA ) + { + ASSERT(offset == bufsize); + break; + } if ( error ) { printk(KERN_ERR "microcode: CPU%d incorrect or corrupt container file\n" -- 2.30.2