Re: [dpdk-stable] [PATCH v2] net/nfp: fix possible buffer overflow

[Alejandro Lucero <alejandro.lucero@netronome.com>]

On Tue, Mar 19, 2019 at 5:43 PM Ferruh Yigit <ferruh.yigit@intel.com> wrote:

> On 3/12/2019 9:56 AM, Alejandro Lucero wrote:
> > On Fri, Mar 8, 2019 at 10:28 AM Pallantla Poornima <
> > pallantlax.poornima@intel.com> wrote:
> >
> >> sprintf function is not secure as it doesn't check the length of string.
> >> More secure function snprintf is used.
> >>
> >> Fixes: 896c265ef9 ("net/nfp: use new CPP interface")
> >> Fixes: c4171b520b ("net/nfp: support PF multiport")
> >> Cc: stable@dpdk.org
> >>
> >> Signed-off-by: Pallantla Poornima <pallantlax.poornima@intel.com>
> >> ---
> >> v2: updated title as suggested.
> >> ---
> >>  drivers/net/nfp/nfp_net.c | 20 ++++++++++++--------
> >>  1 file changed, 12 insertions(+), 8 deletions(-)
> >>
> >> diff --git a/drivers/net/nfp/nfp_net.c b/drivers/net/nfp/nfp_net.c
> >> index a791e95e2..f63def5ef 100644
> >> --- a/drivers/net/nfp/nfp_net.c
> >> +++ b/drivers/net/nfp/nfp_net.c
> >> @@ -3318,9 +3318,9 @@ nfp_pf_create_dev(struct rte_pci_device *dev, int
> >> port, int ports,
> >>                 return -ENOMEM;
> >>
> >>         if (ports > 1)
> >> -               sprintf(port_name, "%s_port%d", dev->device.name,
> port);
> >> +               snprintf(port_name, 100, "%s_port%d", dev->device.name,
> >> port);
> >>         else
> >> -               sprintf(port_name, "%s", dev->device.name);
> >> +               strlcat(port_name, dev->device.name, 100);
> >>
> >>
> >>         if (rte_eal_process_type() == RTE_PROC_PRIMARY) {
> >> @@ -3433,12 +3433,14 @@ nfp_fw_upload(struct rte_pci_device *dev, struct
> >> nfp_nsp *nsp, char *card)
> >>         /* Looking for firmware file in order of priority */
> >>
> >>         /* First try to find a firmware image specific for this device
> */
> >> -       sprintf(serial,
> "serial-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x",
> >> +       snprintf(serial, sizeof(serial),
> >> +
>  "serial-%02x-%02x-%02x-%02x-%02x-%02x-%02x-%02x",
> >>                 cpp->serial[0], cpp->serial[1], cpp->serial[2],
> >> cpp->serial[3],
> >>                 cpp->serial[4], cpp->serial[5], cpp->interface >> 8,
> >>                 cpp->interface & 0xff);
> >>
> >> -       sprintf(fw_name, "%s/%s.nffw", DEFAULT_FW_PATH, serial);
> >> +       snprintf(fw_name, sizeof(fw_name), "%s/%s.nffw",
> DEFAULT_FW_PATH,
> >> +                       serial);
> >>
> >>         PMD_DRV_LOG(DEBUG, "Trying with fw file: %s", fw_name);
> >>         fw_f = open(fw_name, O_RDONLY);
> >> @@ -3446,7 +3448,8 @@ nfp_fw_upload(struct rte_pci_device *dev, struct
> >> nfp_nsp *nsp, char *card)
> >>                 goto read_fw;
> >>
> >>         /* Then try the PCI name */
> >> -       sprintf(fw_name, "%s/pci-%s.nffw", DEFAULT_FW_PATH, dev->
> >> device.name);
> >> +       snprintf(fw_name, sizeof(fw_name), "%s/pci-%s.nffw",
> >> DEFAULT_FW_PATH,
> >> +                       dev->device.name);
> >>
> >>         PMD_DRV_LOG(DEBUG, "Trying with fw file: %s", fw_name);
> >>         fw_f = open(fw_name, O_RDONLY);
> >> @@ -3454,7 +3457,7 @@ nfp_fw_upload(struct rte_pci_device *dev, struct
> >> nfp_nsp *nsp, char *card)
> >>                 goto read_fw;
> >>
> >>         /* Finally try the card type and media */
> >> -       sprintf(fw_name, "%s/%s", DEFAULT_FW_PATH, card);
> >> +       snprintf(fw_name, sizeof(fw_name), "%s/%s", DEFAULT_FW_PATH,
> card);
> >>         PMD_DRV_LOG(DEBUG, "Trying with fw file: %s", fw_name);
> >>         fw_f = open(fw_name, O_RDONLY);
> >>         if (fw_f < 0) {
> >> @@ -3530,8 +3533,9 @@ nfp_fw_setup(struct rte_pci_device *dev, struct
> >> nfp_cpp *cpp,
> >>
> >>         PMD_DRV_LOG(INFO, "Port speed: %u",
> nfp_eth_table->ports[0].speed);
> >>
> >> -       sprintf(card_desc, "nic_%s_%dx%d.nffw", nfp_fw_model,
> >> -               nfp_eth_table->count, nfp_eth_table->ports[0].speed /
> >> 1000);
> >> +       snprintf(card_desc, sizeof(card_desc), "nic_%s_%dx%d.nffw",
> >> +                       nfp_fw_model, nfp_eth_table->count,
> >> +                       nfp_eth_table->ports[0].speed / 1000);
> >>
> >>         nsp = nfp_nsp_open(cpp);
> >>         if (!nsp) {
> >> --
> >> 2.17.2
> >>
> >>
> > I got a compilation error when applying this patch: strlcat can not be
> > found.
> >
> > I guess this patch requires to check for system libraries versions.
> >
>
> Hi Alejandro,
>
>
Hi Ferruh,


> Linux doesn't have the 'strlcat' but there is DPDK implementation of it,
> comes
> with '#include <rte_string_fns.h>' header which is already included in
> this file.
>
> 'strlcat' support is added in this release, 19.05, can you be using an old
> code?
> Can you please double check the build with the latest code?
>
>
I have tried again with tip DPDK and it works fine. I would say I used also
tip the first time, but anyway, it compiles now without problem.

I have also performed some basic tests and it is all fine.

So:

Acked-by: Alejandro Lucero <alejandro.lucero@netronome.com>
Tested-by: Alejandro Lucero <alejandro.lucero@netronome.com>

Thanks!


> Thanks,
> ferruh
>