kvm: svm: fix potential get_num_contig_pages overflow

get_num_contig_pages() could potentially overflow int so make its type
consistent with its usage.

Reported-by: Cfir Cohen <cfir@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 426039285fd1fc5b10796c79278dd784af788545..947c35a1e5459aec234676cb68981b0b60b343e1 100644 (file)
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -6422,11 +6422,11 @@ e_free:
        return ret;
 }
 
-static int get_num_contig_pages(int idx, struct page **inpages,
-                               unsigned long npages)
+static unsigned long get_num_contig_pages(unsigned long idx,
+                               struct page **inpages, unsigned long npages)
 {
        unsigned long paddr, next_paddr;
-       int i = idx + 1, pages = 1;
+       unsigned long i = idx + 1, pages = 1;
 
        /* find the number of contiguous pages starting from idx */
        paddr = __sme_page_pa(inpages[idx]);
@@ -6445,12 +6445,12 @@ static int get_num_contig_pages(int idx, struct page **inpages,
 
 static int sev_launch_update_data(struct kvm *kvm, struct kvm_sev_cmd *argp)
 {
-       unsigned long vaddr, vaddr_end, next_vaddr, npages, size;
+       unsigned long vaddr, vaddr_end, next_vaddr, npages, pages, size, i;
        struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
        struct kvm_sev_launch_update_data params;
        struct sev_data_launch_update_data *data;
        struct page **inpages;
-       int i, ret, pages;
+       int ret;
 
        if (!sev_guest(kvm))
                return -ENOTTY;