Commit 3964994b authored Apr 09, 2007 by Eric Sesterhenn / Snakebyte Committed by Avi Kivity May 03, 2007

KVM: Fix overflow bug in overflow detection code



The expression

   sp - 6 < sp

where sp is a u16 is undefined in C since 'sp - 6' is promoted to int,
and signed overflow is undefined in C.  gcc 4.2 actually warns about it.
Replace with a simpler test.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Avi Kivity <avi@qumranet.com>

parent 5008fdf5

drivers/kvm/vmx.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1182,7 +1182,7 @@ static void inject_rmode_irq(struct kvm_vcpu *vcpu, int irq)
		u16 sp = vmcs_readl(GUEST_RSP);
		u32 ss_limit = vmcs_read32(GUEST_SS_LIMIT);

		if (sp > ss_limit \|\| sp - 6 > sp) {
		if (sp > ss_limit \|\| sp < 6 ) {
		vcpu_printf(vcpu, "%s: #SS, rsp 0x%lx ss 0x%lx limit 0x%x\n",
		__FUNCTION__,
		vmcs_readl(GUEST_RSP),

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