The length documented as

 * @length:     length of the data (multiple of the page size)

Fail with -EINVAL, when user gives a zero length buffer. Right now
'ret' is returned as uninitialized.

Cc: Dave Hansen <[email protected]>
Cc: Borislav Petkov <[email protected]>
Link: https://lore.kernel.org/linux-sgx/X8ehQssnslm194ld@mwanda/
Fixes: c6d26d370767 ("x86/sgx: Add SGX_IOC_ENCLAVE_ADD_PAGES")
Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: Jarkko Sakkinen <[email protected]>
---
 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 c206aee80a04..90a5caf76939 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)
-- 
2.27.0

Reply via email to