crypto: sm3 - fix undefined shift by >= width of value

sm3_compress() calls rol32() with shift >= 32, which causes undefined behavior. This is easily detected by enabling CONFIG_UBSAN. Explicitly AND with 31 to make the behavior well defined. Fixes: 4f0fc16 ("crypto: sm3 - add OSCCA SM3 secure hash") Cc: <[email protected]> # v4.15+ Cc: Gilad Ben-Yossef <[email protected]> Signed-off-by: Eric Biggers <[email protected]> Signed-off-by: Herbert Xu <[email protected]>
numbqq · Jan 10, 2019 · d45a90c · d45a90c
1 parent 1bea445
commit d45a90c
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/crypto/sm3_generic.c b/crypto/sm3_generic.c
@@ -100,7 +100,7 @@ static void sm3_compress(u32 *w, u32 *wt, u32 *m)
 
 	for (i = 0; i <= 63; i++) {
 
-		ss1 = rol32((rol32(a, 12) + e + rol32(t(i), i)), 7);
+		ss1 = rol32((rol32(a, 12) + e + rol32(t(i), i & 31)), 7);
 
 		ss2 = ss1 ^ rol32(a, 12);