[PATCH 3/5] x86/sgx: Make sgx_validate_secinfo() more readable

[Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>]

Split the huge conditional statement to three separate ones in
order to make it easier to understand what is going on in the
validation code.

Cc: Sean Christopherson <sean.j.christpherson@intel.com>
Cc: Shay Katz-zamir <shay.katz-zamir@intel.com>
Cc: Serge Ayoun <serge.ayoun@intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
---
 arch/x86/kernel/cpu/sgx/driver/ioctl.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/sgx/driver/ioctl.c b/arch/x86/kernel/cpu/sgx/driver/ioctl.c
index d5f326411df0..99b1b9776c3a 100644
--- a/arch/x86/kernel/cpu/sgx/driver/ioctl.c
+++ b/arch/x86/kernel/cpu/sgx/driver/ioctl.c
@@ -415,10 +415,15 @@ static int sgx_validate_secinfo(struct sgx_secinfo *secinfo)
 	u64 page_type = secinfo->flags & SGX_SECINFO_PAGE_TYPE_MASK;
 	u64 perm = secinfo->flags & SGX_SECINFO_PERMISSION_MASK;
 
-	if ((secinfo->flags & SGX_SECINFO_RESERVED_MASK) ||
-	    ((perm & SGX_SECINFO_W) && !(perm & SGX_SECINFO_R)) ||
-	    (page_type != SGX_SECINFO_TCS && page_type != SGX_SECINFO_TRIM &&
-	     page_type != SGX_SECINFO_REG))
+	if ((page_type != SGX_SECINFO_REG &&
+	     page_type != SGX_SECINFO_TCS &&
+	     page_type != SGX_SECINFO_TRIM))
+		return -EINVAL;
+
+	if ((perm & SGX_SECINFO_W) && !(perm & SGX_SECINFO_R))
+		return -EINVAL;
+
+	if (secinfo->flags & SGX_SECINFO_RESERVED_MASK)
 		return -EINVAL;
 
 	if (memchr_inv(secinfo->reserved, 0, SGX_SECINFO_RESERVED_SIZE))
-- 
2.20.1