[PATCH net] enetc: Avoid implicit sign extension
From: Claudiu Manoil <claudiu.manoil@nxp.com>
Date: 2021-03-29 13:36:25
Subsystem:
freescale enetc ethernet drivers, networking drivers, the rest · Maintainers:
Claudiu Manoil, Vladimir Oltean, Wei Fang, Clark Wang, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Static analysis tool reports: "Suspicious implicit sign extension - 'flags' with type u8 (8 bit, unsigned) is promoted in 'flags' << 24 to type int (32 bits, signed), then sign-extended to type unsigned long long (64 bits, unsigned). If flags << 24 is greater than 0x7FFFFFFF, the upper bits of the result will all be 1." Use lower_32_bits() to avoid this scenario. Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com> --- drivers/net/ethernet/freescale/enetc/enetc_hw.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/freescale/enetc/enetc_hw.h b/drivers/net/ethernet/freescale/enetc/enetc_hw.h
index 00938f7960a4..07e03df8af94 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_hw.h
+++ b/drivers/net/ethernet/freescale/enetc/enetc_hw.h@@ -535,8 +535,8 @@ static inline __le32 enetc_txbd_set_tx_start(u64 tx_start, u8 flags) { u32 temp; - temp = (tx_start >> 5 & ENETC_TXBD_TXSTART_MASK) | - (flags << ENETC_TXBD_FLAGS_OFFSET); + temp = lower_32_bits(tx_start >> 5 & ENETC_TXBD_TXSTART_MASK) | + (u32)(flags << ENETC_TXBD_FLAGS_OFFSET); return cpu_to_le32(temp); }
--
2.25.1