From: Eric Biggers <ebiggers@xxxxxxxxxx> 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: 4f0fc1600edb ("crypto: sm3 - add OSCCA SM3 secure hash") Cc: <stable@xxxxxxxxxxxxxxx> # v4.15+ Cc: Gilad Ben-Yossef <gilad@xxxxxxxxxxxxx> Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> --- crypto/sm3_generic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/crypto/sm3_generic.c b/crypto/sm3_generic.c index 9a5c60f08aad8..c0cf87ae7ef6d 100644 --- 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); -- 2.20.1