From: Maxim Korotkov <korotkov.maxim.s@xxxxxxxxx> [ Upstream commit 64a8f8f7127da228d59a39e2c5e75f86590f90b4 ] The value of an arithmetic expression "n * id.data" is subject to possible overflow due to a failure to cast operands to a larger data type before performing arithmetic. Used macro for multiplication instead operator for avoiding overflow. Found by Linux Verification Center (linuxtesting.org) with SVACE. Signed-off-by: Maxim Korotkov <korotkov.maxim.s@xxxxxxxxx> Reviewed-by: Alexander Lobakin <alexandr.lobakin@xxxxxxxxx> Reviewed-by: Andrew Lunn <andrew@xxxxxxx> Link: https://lore.kernel.org/r/20221122122901.22294-1-korotkov.maxim.s@xxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/ethtool/ioctl.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c index 57e7238a4136..81fe2422fe58 100644 --- a/net/ethtool/ioctl.c +++ b/net/ethtool/ioctl.c @@ -2008,7 +2008,8 @@ static int ethtool_phys_id(struct net_device *dev, void __user *useraddr) } else { /* Driver expects to be called at twice the frequency in rc */ int n = rc * 2, interval = HZ / n; - u64 count = n * id.data, i = 0; + u64 count = mul_u32_u32(n, id.data); + u64 i = 0; do { rtnl_lock(); -- 2.35.1
