[dpdk-dev] [PATCH 1/3] app/testpmd: fix minor signed overflow in a constant
Julien Cretin
julien.cretin at trust-in-soft.com
Mon May 12 17:35:09 CEST 2014
The expression (192 << 24) has an undefined behavior since:
- the integer constant 192 has type int, and
- 192 x 2^24 is not representable as an int.
Suffixing 192 with U defines a behavior since:
- the integer constant 192U has type unsigned int, and
- the value of (192U << 24) is defined as
(192 x 2^24) % (UINT_MAX + 1)
This minor bug was found using TrustInSoft Analyzer.
Signed-off-by: Julien Cretin <julien.cretin at trust-in-soft.com>
---
app/test-pmd/txonly.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/app/test-pmd/txonly.c b/app/test-pmd/txonly.c
index 1cf2574..5bbd34f 100644
--- a/app/test-pmd/txonly.c
+++ b/app/test-pmd/txonly.c
@@ -76,8 +76,8 @@
#define UDP_SRC_PORT 1024
#define UDP_DST_PORT 1024
-#define IP_SRC_ADDR ((192 << 24) | (168 << 16) | (0 << 8) | 1)
-#define IP_DST_ADDR ((192 << 24) | (168 << 16) | (0 << 8) | 2)
+#define IP_SRC_ADDR ((192U << 24) | (168 << 16) | (0 << 8) | 1)
+#define IP_DST_ADDR ((192U << 24) | (168 << 16) | (0 << 8) | 2)
#define IP_DEFTTL 64 /* from RFC 1340. */
#define IP_VERSION 0x40
--
1.9.1
More information about the dev
mailing list