[PATCH AUTOSEL 5.4 032/187] netfilter: uapi: Avoid undefined left-shift in xt_sctp.h

Sasha Levin
2019-12-27T17:41:47Z

From: Phil Sutter <phil@nwl.cc>

[ Upstream commit 164166558aacea01b99c8c8ffb710d930405ba69 ]

With 'bytes(__u32)' being 32, a left-shift of 31 may happen which is
undefined for the signed 32-bit value 1. Avoid this by declaring 1 as
unsigned.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/uapi/linux/netfilter/xt_sctp.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/uapi/linux/netfilter/xt_sctp.h b/include/uapi/linux/netfilter/xt_sctp.h
index 4bc6d1a08781..b4d804a9fccb 100644
--- a/include/uapi/linux/netfilter/xt_sctp.h
+++ b/include/uapi/linux/netfilter/xt_sctp.h
@@ -41,19 +41,19 @@ struct xt_sctp_info {
#define SCTP_CHUNKMAP_SET(chunkmap, type) \
do { \
(chunkmap)[type / bytes(__u32)] |= \
- 1 << (type % bytes(__u32)); \
+ 1u << (type % bytes(__u32)); \
} while (0)

#define SCTP_CHUNKMAP_CLEAR(chunkmap, type) \
do { \
(chunkmap)[type / bytes(__u32)] &= \
- ~(1 << (type % bytes(__u32))); \
+ ~(1u << (type % bytes(__u32))); \
} while (0)

#define SCTP_CHUNKMAP_IS_SET(chunkmap, type) \
({ \
((chunkmap)[type / bytes (__u32)] & \
- (1 << (type % bytes (__u32)))) ? 1: 0; \
+ (1u << (type % bytes (__u32)))) ? 1: 0; \
})

#define SCTP_CHUNKMAP_RESET(chunkmap) \
--
2.20.1