Re: [PATCH] net: dsa: b53: Fix dereference of null dev
From: Vladimir Oltean <olteanv@gmail.com>
Date: 2021-06-12 15:04:02
Also in:
kernel-janitors, lkml
On Sat, Jun 12, 2021 at 03:44:07PM +0100, Colin King wrote:
quoted hunk ↗ jump to hunk
From: Colin Ian King <redacted> Currently pointer priv is dereferencing dev before dev is being null checked so a potential null pointer dereference can occur. Fix this by only assigning and using priv if dev is not-null. Addresses-Coverity: ("Dereference before null check") Fixes: 16994374a6fc ("net: dsa: b53: Make SRAB driver manage port interrupts") Signed-off-by: Colin Ian King <redacted> --- drivers/net/dsa/b53/b53_srab.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)diff --git a/drivers/net/dsa/b53/b53_srab.c b/drivers/net/dsa/b53/b53_srab.c index aaa12d73784e..e77ac598f859 100644 --- a/drivers/net/dsa/b53/b53_srab.c +++ b/drivers/net/dsa/b53/b53_srab.c@@ -629,11 +629,13 @@ static int b53_srab_probe(struct platform_device *pdev) static int b53_srab_remove(struct platform_device *pdev) { struct b53_device *dev = platform_get_drvdata(pdev); - struct b53_srab_priv *priv = dev->priv; - b53_srab_intr_set(priv, false); - if (dev) + if (dev) { + struct b53_srab_priv *priv = dev->priv; + + b53_srab_intr_set(priv, false); b53_switch_remove(dev); + } return 0; }-- 2.31.1
I think the better question is how can "dev" be NULL in the first place, since b53_srab_probe() does an unconditional platform_set_drvdata() with what appears to be a non-NULL dev.