From a4b9c48b96517ff4780b22a784e7537eac5dc21b Mon Sep 17 00:00:00 2001 From: Jarkko Sakkinen Date: Thu, 3 Dec 2020 20:35:27 +0200 Subject: [PATCH] x86/sgx: Return -EINVAL on a zero length buffer in sgx_ioc_enclave_add_pages() The sgx_enclave_add_pages.length field is documented as * @length: length of the data (multiple of the page size) Fail with -EINVAL, when the caller gives a zero length buffer of data to be added as pages to an enclave. Right now 'ret' is returned as uninitialized in that case. [ bp: Flesh out commit message. ] Fixes: c6d26d370767 ("x86/sgx: Add SGX_IOC_ENCLAVE_ADD_PAGES") Reported-by: Dan Carpenter Signed-off-by: Jarkko Sakkinen Signed-off-by: Borislav Petkov Link: https://lore.kernel.org/linux-sgx/X8ehQssnslm194ld@mwanda/ Link: https://lkml.kernel.org/r/20201203183527.139317-1-jarkko@kernel.org --- arch/x86/kernel/cpu/sgx/ioctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c index c206aee..90a5caf 100644 --- a/arch/x86/kernel/cpu/sgx/ioctl.c +++ b/arch/x86/kernel/cpu/sgx/ioctl.c @@ -428,7 +428,7 @@ static long sgx_ioc_enclave_add_pages(struct sgx_encl *encl, void __user *arg) !IS_ALIGNED(add_arg.src, PAGE_SIZE)) return -EINVAL; - if (add_arg.length & (PAGE_SIZE - 1)) + if (!add_arg.length || add_arg.length & (PAGE_SIZE - 1)) return -EINVAL; if (add_arg.offset + add_arg.length - PAGE_SIZE >= encl->size) -- 2.7.4