Re: [PATCH] net: dsa: avoid null pointer dereference on p->phy
From: Florian Fainelli <f.fainelli@gmail.com>
Date: 2017-09-23 17:21:29
Also in:
kernel-janitors, lkml
On 09/23/2017 09:57 AM, Colin King wrote:
From: Colin Ian King <redacted>
Currently p->phy is being null checked in several places to avoid
null pointer dereferences on p->phy, however, the final call
to phy_attached_info on p->phy when p->phy will perform a null
pointer dereference. Fix this by simply moving the call into
the previous code block that is only executed if p->phy is
not null.
Detected by CoverityScan, CID#1457034 ("Dereference after null check")The code flow is not exactly easy to read, but I don't see how we can actually wind up in that situation because we check the return values of of_phy_connect() and dsa_slave_phy_connect() earlier on.
quoted hunk ↗ jump to hunk
Fixes: 2220943a21e2 ("phy: Centralise print about attached phy") Signed-off-by: Colin Ian King <redacted> --- net/dsa/slave.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)diff --git a/net/dsa/slave.c b/net/dsa/slave.c index 02ace7d462c4..29ab4e98639b 100644 --- a/net/dsa/slave.c +++ b/net/dsa/slave.c@@ -1115,10 +1115,9 @@ static int dsa_slave_phy_setup(struct net_device *slave_dev) of_phy_deregister_fixed_link(port_dn); return ret; } + phy_attached_info(p->phy); } - phy_attached_info(p->phy); - return 0; }
-- Florian