[PATCH 08/22] crypto: x86/glue_helper - add check for xts input length equal to zero

[Andrei Botila]

From: Andrei Botila <andrei.botila@xxxxxxx>

Standardize the way input lengths equal to 0 are handled in all skcipher
algorithms. All the algorithms return 0 for input lengths equal to zero.

Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Signed-off-by: Andrei Botila <andrei.botila@xxxxxxx>
---
 arch/x86/crypto/glue_helper.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/x86/crypto/glue_helper.c b/arch/x86/crypto/glue_helper.c
index d3d91a0abf88..cc5042c72910 100644
--- a/arch/x86/crypto/glue_helper.c
+++ b/arch/x86/crypto/glue_helper.c
@@ -275,6 +275,9 @@ int glue_xts_req_128bit(const struct common_glue_ctx *gctx,
 	unsigned int nbytes, tail;
 	int err;
 
+	if (!req->cryptlen)
+		return 0;
+
 	if (req->cryptlen < XTS_BLOCK_SIZE)
 		return -EINVAL;
 
-- 
2.17.1