On Wed, 11 Jan 2023 12:05:03 +0300 Esina Ekaterina wrote: > Subject: [PATCH v3] net: wan: Add checks for NULL for utdm in > undo_uhdlc_init and unmap_si_regs
net: wan: prevent null-deref on error path for non-tdm case > If uhdlc_priv_tsa != 1 then utdm is not initialized. > And if ret != NULL then goto undo_uhdlc_init, where > utdm is dereferenced. Same if dev == NULL. > > Found by Linux Verification Center (linuxtesting.org) with SVACE. I did the indentation to make the content stand out in the email, there should be no indentation in the actual msg, sorry. > --- a/drivers/net/wan/fsl_ucc_hdlc.c > +++ b/drivers/net/wan/fsl_ucc_hdlc.c > @@ -1243,9 +1243,11 @@ static int ucc_hdlc_probe(struct platform_device *pdev) > free_dev: > free_netdev(dev); > undo_uhdlc_init: > - iounmap(utdm->siram); > + if (utdm != NULL) and here just: if (utdm) comparing to NULL or zero is less idiomatic in kernel C. > + iounmap(utdm->siram); > unmap_si_regs: > - iounmap(utdm->si_regs); > + if (utdm != NULL) > + iounmap(utdm->si_regs);