[Linux-kernel-mentees][PATCH v2] packet: Fix undefined behavior in bit shift

From: Jiunn Chang
Date: Wed Jun 26 2019 - 23:25:40 EST


Shifting signed 32-bit value by 31 bits is undefined. Changing most
significant bit to unsigned.

Changes included in v2:
- use subsystem specific subject lines
- CC required mailing lists

Signed-off-by: Jiunn Chang <c0d1n61at3@xxxxxxxxx>
---
include/uapi/linux/if_packet.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/uapi/linux/if_packet.h b/include/uapi/linux/if_packet.h
index 467b654bd4c7..3d884d68eb30 100644
--- a/include/uapi/linux/if_packet.h
+++ b/include/uapi/linux/if_packet.h
@@ -123,7 +123,7 @@ struct tpacket_auxdata {
/* Rx and Tx ring - header status */
#define TP_STATUS_TS_SOFTWARE (1 << 29)
#define TP_STATUS_TS_SYS_HARDWARE (1 << 30) /* deprecated, never set */
-#define TP_STATUS_TS_RAW_HARDWARE (1 << 31)
+#define TP_STATUS_TS_RAW_HARDWARE (1U << 31)

/* Rx ring - feature request bits */
#define TP_FT_REQ_FILL_RXHASH 0x1
--
2.22.0