[dpdk-dev] [dpdk-stable] [PATCH] eal: fix dereference before null check

[wangyunjian]

> -----Original Message-----
> From: Ferruh Yigit [mailto:ferruh.yigit at intel.com]
> Sent: Thursday, October 15, 2020 1:03 AM
> To: wangyunjian <wangyunjian at huawei.com>; dev at dpdk.org
> Cc: david.marchand at redhat.com; jerinj at marvell.com; hkalra at marvell.com;
> Lilijun (Jerry) <jerry.lilijun at huawei.com>; xudingke <xudingke at huawei.com>;
> stable at dpdk.org
> Subject: Re: [dpdk-stable] [dpdk-dev] [PATCH] eal: fix dereference before null
> check
> 
> On 9/19/2020 11:34 AM, wangyunjian wrote:
> > From: Yunjian Wang <wangyunjian at huawei.com>
> >
> > This patch fixes (dereference after null check) coverity issue.
> > The intr_handle may be a null pointer which led to this issue.
> >
> > Coverity issue: 357695, 357751
> > Fixes: 05c4105738d8 ("trace: add interrupt tracepoints")
> > Cc: stable at dpdk.org
> >
> > Signed-off-by: Yunjian Wang <wangyunjian at huawei.com>
> > ---
> >   lib/librte_eal/freebsd/eal_interrupts.c | 6 ++++--
> >   lib/librte_eal/linux/eal_interrupts.c   | 6 ++++--
> >   2 files changed, 8 insertions(+), 4 deletions(-)
> >
> > diff --git a/lib/librte_eal/freebsd/eal_interrupts.c
> > b/lib/librte_eal/freebsd/eal_interrupts.c
> > index 6d53d33c8..028ab457a 100644
> > --- a/lib/librte_eal/freebsd/eal_interrupts.c
> > +++ b/lib/librte_eal/freebsd/eal_interrupts.c
> > @@ -380,7 +380,8 @@ rte_intr_enable(const struct rte_intr_handle
> *intr_handle)
> >   	}
> >
> >   out:
> > -	rte_eal_trace_intr_enable(intr_handle, rc);
> > +	if (intr_handle)
> > +		rte_eal_trace_intr_enable(intr_handle, rc);
> >   	return rc;
> >   }
> >
> > @@ -418,7 +419,8 @@ rte_intr_disable(const struct rte_intr_handle
> *intr_handle)
> >   		break;
> >   	}
> >   out:
> > -	rte_eal_trace_intr_disable(intr_handle, rc);
> > +	if (intr_handle)
> > +		rte_eal_trace_intr_disable(intr_handle, rc);
> >   	return rc;
> >   }
> >
> > diff --git a/lib/librte_eal/linux/eal_interrupts.c
> > b/lib/librte_eal/linux/eal_interrupts.c
> > index 13db5c4e8..e46443873 100644
> > --- a/lib/librte_eal/linux/eal_interrupts.c
> > +++ b/lib/librte_eal/linux/eal_interrupts.c
> > @@ -725,7 +725,8 @@ rte_intr_enable(const struct rte_intr_handle
> *intr_handle)
> >   		break;
> >   	}
> >   out:
> > -	rte_eal_trace_intr_enable(intr_handle, rc);
> > +	if (intr_handle)
> > +		rte_eal_trace_intr_enable(intr_handle, rc);
> >   	return rc;
> 
> It looks like whole function requires 'intr_handle' to be not NULL, so what do
> you think add following at the very beginning of the function and remove other
> 'intr_handle' NULL checks from function:
> 
> if (intr_handle == NULL)
> 	return -1;

Agree, I will add them in next version.

Thanks,
Yunjian

> 
> >   }
> >
> > @@ -852,7 +853,8 @@ rte_intr_disable(const struct rte_intr_handle
> *intr_handle)
> >   		break;
> >   	}
> >   out:
> > -	rte_eal_trace_intr_disable(intr_handle, rc);
> > +	if (intr_handle)
> > +		rte_eal_trace_intr_disable(intr_handle, rc);
> >   	return rc;
> >   }
> >
> >