[PATCH net] net: phylink: correctly validate returned PCS in phylink_inband_caps
From: Christian Marangi <ansuelsmth@gmail.com>
Date: 2026-08-17 21:30:22
Also in:
lkml, stable
Subsystem:
ethernet phy library, networking drivers, sff/sfp/sfp+ module support, the rest · Maintainers:
Andrew Lunn, Heiner Kallweit, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Russell King, Linus Torvalds
In phylink_inband_caps(), the PCS returned by mac_select_pcs is only
checked if NULL but mac_select_pcs can also return an error pointer.
This can cause a kernel panic as phylink_pcs_inband_caps() only checks
if passed PCS is not NULL and directly dereference ops from the phylink_pcs
struct.
Use the IS_ERR_OR_NULL macro to address both case where the returned
PCS can be NULL or an error pointer and prevent a kernel panic.
Cc: stable@vger.kernel.org
Fixes: df874f9e52c3 ("net: phylink: add pcs_inband_caps() method")
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
drivers/net/phy/phylink.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 5b8e956902fb..3ec3bb439109 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c@@ -964,7 +964,7 @@ static unsigned int phylink_inband_caps(struct phylink *pl, return 0; pcs = pl->mac_ops->mac_select_pcs(pl->config, interface); - if (!pcs) + if (IS_ERR_OR_NULL(pcs)) return 0; return phylink_pcs_inband_caps(pcs, interface);
--
2.53.0