Re: [PATCH net-next] net: phylink: fix NULL pl->pcs dereference during phylink_pcs_poll_start
From: "Russell King (Oracle)" <linux@armlinux.org.uk>
Date: 2022-06-29 19:42:16
On Wed, Jun 29, 2022 at 10:33:58PM +0300, Vladimir Oltean wrote:
The current link mode of the phylink instance may not require an
attached PCS. However, phylink_major_config() unconditionally
dereferences this potentially NULL pointer when restarting the link poll
timer, which will panic the kernel.
Fix the problem by checking whether a PCS exists in phylink_pcs_poll_start(),
otherwise do nothing. The code prior to the blamed patch also only
looked at pcs->poll within an "if (pcs)" block.
Fixes: bfac8c490d60 ("net: phylink: disable PCS polling over major configuration")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>Thanks. Reviewed-by: Russell King (Oracle) <redacted> -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!