commit 8827b0fb66cab9f7978c4e66dad4cf3c0989a72e
author Peter Maydell <peter.maydell@linaro.org> Thu Jun 27 15:03:51 2013 +0100
committer Peter Maydell <peter.maydell@linaro.org> Mon Jul 15 16:17:30 2013 +0100
tree 12dd2050248886384769cc99dc27222437b2bb3a
parent 528622421eb1be95eaadfe91e8e11729d1e46431

sd/pl181.c: Avoid undefined shift behaviour in RWORD macro

Add a cast to avoid potentially shifting into the sign bit of
a signed value, which is undefined behaviour in C.

(Detected with clang's -fsanitize=undefined.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1372341831-4264-1-git-send-email-peter.maydell@linaro.org

hw/sd/pl181.c

diff --git a/hw/sd/pl181.c b/hw/sd/pl181.c
index 4b17234..f5eb1e4 100644
--- a/hw/sd/pl181.c
+++ b/hw/sd/pl181.c
@@ -175,7 +175,7 @@
     if (rlen < 0)
         goto error;
     if (s->cmd & PL181_CMD_RESPONSE) {
-#define RWORD(n) ((response[n] << 24) | (response[n + 1] << 16) \
+#define RWORD(n) (((uint32_t)response[n] << 24) | (response[n + 1] << 16) \
                   | (response[n + 2] << 8) | response[n + 3])
         if (rlen == 0 || (rlen == 4 && (s->cmd & PL181_CMD_LONGRESP)))
             goto error;