From 8a9e74fd34212dd91bec5ed38abc5a9b1a68650c Mon Sep 17 00:00:00 2001 From: Nikita Kiryushin Date: Fri, 15 Mar 2024 20:50:52 +0300 Subject: [PATCH] net: phy: fix phy_read_poll_timeout argument type in genphy_loopback BugLink: https://bugs.launchpad.net/bugs/2060097 [ Upstream commit 32fa4366cc4da1c97b725a0066adf43c6b298f37 ] 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 Signed-off-by: Sasha Levin (cherry picked from commit 954b72d92e03ae6a79bb8f3d13a383f9113270a2) Signed-off-by: Paolo Pisati --- drivers/net/phy/phy_device.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 3ad9bbf65cbe..6125418ca93f 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -2706,8 +2706,8 @@ 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);