From: Pavel Skripkin paskripkin@gmail.com

stable inclusion from stable-v4.19.199 commit 11e9d163d631198bb3eb41a677a61b499516c0f7 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/pulls/8979 CVE: CVE-2021-47311

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

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commit ad297cd2db8953e2202970e9504cab247b6c7cb4 upstream.

adpt is netdev private data and it cannot be used after free_netdev() call. Using adpt after free_netdev() can cause UAF bug. Fix it by moving free_netdev() at the end of the function.

Fixes: 54e19bc74f33 ("net: qcom/emac: do not use devm on internal phy pdev") Signed-off-by: Pavel Skripkin paskripkin@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Ze Zuo zuoze1@huawei.com --- drivers/net/ethernet/qualcomm/emac/emac.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/qualcomm/emac/emac.c b/drivers/net/ethernet/qualcomm/emac/emac.c index b10f2bcf8506..938602864c24 100644 --- a/drivers/net/ethernet/qualcomm/emac/emac.c +++ b/drivers/net/ethernet/qualcomm/emac/emac.c @@ -754,12 +754,13 @@ static int emac_remove(struct platform_device *pdev)

put_device(&adpt->phydev->mdio.dev); mdiobus_unregister(adpt->mii_bus); - free_netdev(netdev);

if (adpt->phy.digital) iounmap(adpt->phy.digital); iounmap(adpt->phy.base);

+ free_netdev(netdev); + return 0; }