On 10/06/2017 08:19 PM, Matt Fleming wrote:
On Sat, 30 Sep, at 11:17:32AM, Dan Carpenter wrote:If "qcaps.capsule_count" is ULONG_MAX then "qcaps.capsule_count + 1" will overflow to zero and kcalloc() will return the ZERO_SIZE_PTR. We try to dereference it inside the loop and crash. Fixes: ff6301dabc3c ("efi: Add efi_test driver for exporting UEFI runtime service interfaces") Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com> diff --git a/drivers/firmware/efi/test/efi_test.c b/drivers/firmware/efi/test/efi_test.c index 08129b7b80ab..41c48a1e8baa 100644 --- a/drivers/firmware/efi/test/efi_test.c +++ b/drivers/firmware/efi/test/efi_test.c @@ -593,6 +593,9 @@ static long efi_runtime_query_capsulecaps(unsigned long arg) if (copy_from_user(&qcaps, qcaps_user, sizeof(qcaps))) return -EFAULT;+ if (qcaps.capsule_count == ULONG_MAX)+ return -EINVAL; + capsules = kcalloc(qcaps.capsule_count + 1, sizeof(efi_capsule_header_t), GFP_KERNEL); if (!capsules)This looks OK to me. Ivan?
Acked-by: Ivan Hu <ivan...@canonical.com> -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
