[PATCH 4.19 120/168] fsl/fman: use 32-bit unsigned integer

Greg Kroah-Hartman
2020-08-17T17:19:58Z

From: Florinel Iordache <florinel.iordache@nxp.com>

[ Upstream commit 99f47abd9f7bf6e365820d355dc98f6955a562df ]

Potentially overflowing expression (ts_freq << 16 and intgr << 16)
declared as type u32 (32-bit unsigned) is evaluated using 32-bit
arithmetic and then used in a context that expects an expression of
type u64 (64-bit unsigned) which ultimately is used as 16-bit
unsigned by typecasting to u16. Fixed by using an unsigned 32-bit
integer since the value is truncated anyway in the end.

Fixes: 414fd46e7762 ("fsl/fman: Add FMan support")
Signed-off-by: Florinel Iordache <florinel.iordache@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/freescale/fman/fman.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fman/fman.c b/drivers/net/ethernet/freescale/fman/fman.c
index 21d8023535ae4..eba7e54ecf85b 100644
--- a/drivers/net/ethernet/freescale/fman/fman.c
+++ b/drivers/net/ethernet/freescale/fman/fman.c
@@ -1396,8 +1396,7 @@ static void enable_time_stamp(struct fman *fman)
{
struct fman_fpm_regs __iomem *fpm_rg = fman->fpm_regs;
u16 fm_clk_freq = fman->state->fm_clk_freq;
- u32 tmp, intgr, ts_freq;
- u64 frac;
+ u32 tmp, intgr, ts_freq, frac;

ts_freq = (u32)(1 << fman->state->count1_micro_bit);
/* configure timestamp so that bit 8 will count 1 microsecond
--
2.25.1