On Mon, Apr 04, 2022 at 09:49:18AM -0700, Reinette Chatre wrote: > User provided offset and length is validated when parsing the parameters > of the SGX_IOC_ENCLAVE_ADD_PAGES ioctl(). Extract this validation > into a utility that can be used by the SGX2 ioctl()s that will > also provide these values. > > Signed-off-by: Reinette Chatre <reinette.chatre@xxxxxxxxx> > --- > No changes since V2 > > Changes since V1: > - New patch > > arch/x86/kernel/cpu/sgx/ioctl.c | 28 ++++++++++++++++++++++------ > 1 file changed, 22 insertions(+), 6 deletions(-) > > diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c > index 83df20e3e633..f487549bccba 100644 > --- a/arch/x86/kernel/cpu/sgx/ioctl.c > +++ b/arch/x86/kernel/cpu/sgx/ioctl.c > @@ -372,6 +372,26 @@ static int sgx_encl_add_page(struct sgx_encl *encl, unsigned long src, > return ret; > } > > +/* > + * Ensure user provided offset and length values are valid for > + * an enclave. > + */ > +static int sgx_validate_offset_length(struct sgx_encl *encl, > + unsigned long offset, > + unsigned long length) > +{ > + if (!IS_ALIGNED(offset, PAGE_SIZE)) > + return -EINVAL; > + > + if (!length || length & (PAGE_SIZE - 1)) > + return -EINVAL; > + > + if (offset + length - PAGE_SIZE >= encl->size) > + return -EINVAL; > + > + return 0; > +} > + > /** > * sgx_ioc_enclave_add_pages() - The handler for %SGX_IOC_ENCLAVE_ADD_PAGES > * @encl: an enclave pointer > @@ -425,14 +445,10 @@ static long sgx_ioc_enclave_add_pages(struct sgx_encl *encl, void __user *arg) > if (copy_from_user(&add_arg, arg, sizeof(add_arg))) > return -EFAULT; > > - if (!IS_ALIGNED(add_arg.offset, PAGE_SIZE) || > - !IS_ALIGNED(add_arg.src, PAGE_SIZE)) > - return -EINVAL; > - > - if (!add_arg.length || add_arg.length & (PAGE_SIZE - 1)) > + if (!IS_ALIGNED(add_arg.src, PAGE_SIZE)) > return -EINVAL; > > - if (add_arg.offset + add_arg.length - PAGE_SIZE >= encl->size) > + if (sgx_validate_offset_length(encl, add_arg.offset, add_arg.length)) > return -EINVAL; > > if (copy_from_user(&secinfo, (void __user *)add_arg.secinfo, > -- > 2.25.1 > Reviewed-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx> BR, Jarkko