From: Masahiro Yamada <masahiroy@kernel.org> stable inclusion from stable-v4.19.247 commit 5534bcd7c40299862237c4a8fd9c5031b3db1538 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBPK8Q CVE: CVE-2022-49350 Reference: https://web.git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/... -------------------------------- [ Upstream commit 35b42dce619701f1300fb8498dae82c9bb1f0263 ] EXPORT_SYMBOL and __init is a bad combination because the .init.text section is freed up after the initialization. Hence, modules cannot use symbols annotated __init. The access to a freed symbol may end up with kernel panic. modpost used to detect it, but it has been broken for a decade. Recently, I fixed modpost so it started to warn it again, then this showed up in linux-next builds. There are two ways to fix it: - Remove __init - Remove EXPORT_SYMBOL I chose the latter for this case because the only in-tree call-site, drivers/net/phy/phy_device.c is never compiled as modular. (CONFIG_PHYLIB is boolean) Fixes: 90eff9096c01 ("net: phy: Allow splitting MDIO bus/device support from PHYs") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Wenyu Huang <huangwenyu5@huawei.com> --- drivers/net/phy/mdio_bus.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c index 82cc1983c09a..35937175c4e8 100644 --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -745,7 +745,6 @@ int __init mdio_bus_init(void) return ret; } -EXPORT_SYMBOL_GPL(mdio_bus_init); #if IS_ENABLED(CONFIG_PHYLIB) void mdio_bus_exit(void) -- 2.34.1