From: Nikita Kiryushin Date: Fri, 15 Mar 2024 17:50:52 +0000 (+0300) Subject: net: phy: fix phy_read_poll_timeout argument type in genphy_loopback X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=32fa4366cc4da1c97b725a0066adf43c6b298f37;p=linux.git net: phy: fix phy_read_poll_timeout argument type in genphy_loopback read_poll_timeout inside phy_read_poll_timeout can set val negative in some cases (for example, __mdiobus_read inside phy_read can return -EOPNOTSUPP). Supposedly, commit 4ec732951702 ("net: phylib: fix phy_read*_poll_timeout()") should fix problems with wrong-signed vals, but I do not see how as val is sent to phy_read as is and __val = phy_read (not val) is checked for sign. Change val type for signed to allow better error handling as done in other phy_read_poll_timeout callers. This will not fix any error handling by itself, but allows, for example, to modify cond with appropriate sign check or check resulting val separately. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 014068dcb5b1 ("net: phy: genphy_loopback: add link speed configuration") Signed-off-by: Nikita Kiryushin Reviewed-by: Russell King (Oracle) Link: https://lore.kernel.org/r/20240315175052.8049-1-kiryushin@ancud.ru Signed-off-by: Paolo Abeni --- diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 8297ef681bf5d..6c6ec94757092 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -2831,8 +2831,8 @@ EXPORT_SYMBOL(genphy_resume); int genphy_loopback(struct phy_device *phydev, bool enable) { if (enable) { - u16 val, ctl = BMCR_LOOPBACK; - int ret; + u16 ctl = BMCR_LOOPBACK; + int ret, val; ctl |= mii_bmcr_encode_fixed(phydev->speed, phydev->duplex);