From: Jan Beulich jbeulich@suse.com
commit e11423d6721dd63b23fb41ade5e8d0b448b17780 upstream.
xen_pfn_t is the same size as int only on 32-bit builds (and not even on Arm32). Hence pfns[] can't be used directly to read individual error values returned from xen_remap_domain_mfn_array(); every other error indicator would be skipped/ignored on 64-bit.
Fixes: 3ad0876554ca ("xen/privcmd: add IOCTL_PRIVCMD_MMAP_RESOURCE") Cc: stable@vger.kernel.org Signed-off-by: Jan Beulich jbeulich@suse.com Reviewed-by: Boris Ostrovsky boris.ostrovsky@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
Link: https://lore.kernel.org/r/aa6d6a67-6889-338a-a910-51e889f792d5@suse.com Signed-off-by: Juergen Gross jgross@suse.com --- drivers/xen/privcmd.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
--- a/drivers/xen/privcmd.c +++ b/drivers/xen/privcmd.c @@ -835,11 +835,12 @@ static long privcmd_ioctl_mmap_resource( unsigned int domid = (xdata.flags & XENMEM_rsrc_acq_caller_owned) ? DOMID_SELF : kdata.dom; - int num; + int num, *errs = (int *)pfns;
+ BUILD_BUG_ON(sizeof(*errs) > sizeof(*pfns)); num = xen_remap_domain_mfn_array(vma, kdata.addr & PAGE_MASK, - pfns, kdata.num, (int *)pfns, + pfns, kdata.num, errs, vma->vm_page_prot, domid, vma->vm_private_data); @@ -849,7 +850,7 @@ static long privcmd_ioctl_mmap_resource( unsigned int i;
for (i = 0; i < num; i++) { - rc = pfns[i]; + rc = errs[i]; if (rc < 0) break; }