From 062d5e9b0d714f449b261bb522eadaaf6f00f438 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Thu, 21 Jan 2010 12:19:07 +0100 Subject: [PATCH] KVM: S390: fix potential array overrun in intercept handling kvm_handle_sie_intercept uses a jump table to get the intercept handler for a SIE intercept. Static code analysis revealed a potential problem: the intercept_funcs jump table was defined to contain (0x48 >> 2) entries, but we only checked for code > 0x48 which would cause an off-by-one array overflow if code == 0x48. Use the compiler and ARRAY_SIZE to automatically set the limits. Cc: stable@kernel.org Signed-off-by: Christian Borntraeger Signed-off-by: Marcelo Tosatti --- arch/s390/kvm/intercept.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c index ba9d8a7bc1ac..b40096494e46 100644 --- a/arch/s390/kvm/intercept.c +++ b/arch/s390/kvm/intercept.c @@ -213,7 +213,7 @@ static int handle_instruction_and_prog(struct kvm_vcpu *vcpu) return rc2; } -static const intercept_handler_t intercept_funcs[0x48 >> 2] = { +static const intercept_handler_t intercept_funcs[] = { [0x00 >> 2] = handle_noop, [0x04 >> 2] = handle_instruction, [0x08 >> 2] = handle_prog, @@ -230,7 +230,7 @@ int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu) intercept_handler_t func; u8 code = vcpu->arch.sie_block->icptcode; - if (code & 3 || code > 0x48) + if (code & 3 || (code >> 2) >= ARRAY_SIZE(intercept_funcs)) return -ENOTSUPP; func = intercept_funcs[code >> 2]; if (func) -- 2.34.1