LinuxLists.cc - [PATCH net-next] macvlan: Replace strncpy() by strscpy()

2019-05-27 19:20:54

Subject: [PATCH net-next] macvlan: Replace strncpy() by strscpy()

The strncpy() function is being deprecated. Replace it by the safer
strscpy() and fix the following Coverity warning:

"Calling strncpy with a maximum size argument of 16 bytes on destination
array ifrr.ifr_ifrn.ifrn_name of size 16 bytes might leave the destination
string unterminated."

Notice that, unlike strncpy(), strscpy() always null-terminates the
destination string.

Addresses-Coverity-ID: 1445537 ("Buffer not null terminated")
Signed-off-by: Gustavo A. R. Silva <[email protected]>
---
drivers/net/macvlan.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index 61550122b563..0ccabde8e9c9 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -831,7 +831,7 @@ static int macvlan_do_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
struct ifreq ifrr;
int err = -EOPNOTSUPP;

- strncpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
+ strscpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
ifrr.ifr_ifru = ifr->ifr_ifru;

switch (cmd) {
--
2.21.0

2019-05-27 21:23:10

by Stephen Hemminger

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Subject: Re: [PATCH net-next] macvlan: Replace strncpy() by strscpy()

On Mon, 27 May 2019 13:38:55 -0500
"Gustavo A. R. Silva" <[email protected]> wrote:

> The strncpy() function is being deprecated. Replace it by the safer
> strscpy() and fix the following Coverity warning:
>
> "Calling strncpy with a maximum size argument of 16 bytes on destination
> array ifrr.ifr_ifrn.ifrn_name of size 16 bytes might leave the destination
> string unterminated."
>
> Notice that, unlike strncpy(), strscpy() always null-terminates the
> destination string.
>
> Addresses-Coverity-ID: 1445537 ("Buffer not null terminated")
> Signed-off-by: Gustavo A. R. Silva <[email protected]>
> ---
> drivers/net/macvlan.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
> index 61550122b563..0ccabde8e9c9 100644
> --- a/drivers/net/macvlan.c
> +++ b/drivers/net/macvlan.c
> @@ -831,7 +831,7 @@ static int macvlan_do_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
> struct ifreq ifrr;
> int err = -EOPNOTSUPP;
>
> - strncpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
> + strscpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
> ifrr.ifr_ifru = ifr->ifr_ifru;
>
> switch (cmd) {

Why not use strlcpy like all the other places IFNAMSIZ is copied?

2019-05-27 21:49:32

by Gustavo A. R. Silva

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Subject: Re: [PATCH net-next] macvlan: Replace strncpy() by strscpy()

On 5/27/19 4:20 PM, Stephen Hemminger wrote:
> On Mon, 27 May 2019 13:38:55 -0500
> "Gustavo A. R. Silva" <[email protected]> wrote:
>
>> The strncpy() function is being deprecated. Replace it by the safer
>> strscpy() and fix the following Coverity warning:
>>
>> "Calling strncpy with a maximum size argument of 16 bytes on destination
>> array ifrr.ifr_ifrn.ifrn_name of size 16 bytes might leave the destination
>> string unterminated."
>>
>> Notice that, unlike strncpy(), strscpy() always null-terminates the
>> destination string.
>>
>> Addresses-Coverity-ID: 1445537 ("Buffer not null terminated")
>> Signed-off-by: Gustavo A. R. Silva <[email protected]>
>> ---
>> drivers/net/macvlan.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
>> index 61550122b563..0ccabde8e9c9 100644
>> --- a/drivers/net/macvlan.c
>> +++ b/drivers/net/macvlan.c
>> @@ -831,7 +831,7 @@ static int macvlan_do_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
>> struct ifreq ifrr;
>> int err = -EOPNOTSUPP;
>>
>> - strncpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
>> + strscpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
>> ifrr.ifr_ifru = ifr->ifr_ifru;
>>
>> switch (cmd) {
>
> Why not use strlcpy like all the other places IFNAMSIZ is copied?
>

strlcpy() is also being deprecated.

--
Gustavo

2019-05-27 21:51:02

by Stephen Hemminger

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Subject: Re: [PATCH net-next] macvlan: Replace strncpy() by strscpy()

On Mon, 27 May 2019 16:28:05 -0500
"Gustavo A. R. Silva" <[email protected]> wrote:

> On 5/27/19 4:20 PM, Stephen Hemminger wrote:
> > On Mon, 27 May 2019 13:38:55 -0500
> > "Gustavo A. R. Silva" <[email protected]> wrote:
> >
> >> The strncpy() function is being deprecated. Replace it by the safer
> >> strscpy() and fix the following Coverity warning:
> >>
> >> "Calling strncpy with a maximum size argument of 16 bytes on destination
> >> array ifrr.ifr_ifrn.ifrn_name of size 16 bytes might leave the destination
> >> string unterminated."
> >>
> >> Notice that, unlike strncpy(), strscpy() always null-terminates the
> >> destination string.
> >>
> >> Addresses-Coverity-ID: 1445537 ("Buffer not null terminated")
> >> Signed-off-by: Gustavo A. R. Silva <[email protected]>
> >> ---
> >> drivers/net/macvlan.c | 2 +-
> >> 1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
> >> index 61550122b563..0ccabde8e9c9 100644
> >> --- a/drivers/net/macvlan.c
> >> +++ b/drivers/net/macvlan.c
> >> @@ -831,7 +831,7 @@ static int macvlan_do_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
> >> struct ifreq ifrr;
> >> int err = -EOPNOTSUPP;
> >>
> >> - strncpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
> >> + strscpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
> >> ifrr.ifr_ifru = ifr->ifr_ifru;
> >>
> >> switch (cmd) {
> >
> > Why not use strlcpy like all the other places IFNAMSIZ is copied?
> >
>
> strlcpy() is also being deprecated.

Are you going to fix all these:
$ git grep strlcpy | grep IFNAMSIZ| wc -l
47

2019-05-29 07:02:31

by David Miller

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Subject: Re: [PATCH net-next] macvlan: Replace strncpy() by strscpy()

From: "Gustavo A. R. Silva" <[email protected]>
Date: Mon, 27 May 2019 13:38:55 -0500

> The strncpy() function is being deprecated. Replace it by the safer
> strscpy() and fix the following Coverity warning:
>
> "Calling strncpy with a maximum size argument of 16 bytes on destination
> array ifrr.ifr_ifrn.ifrn_name of size 16 bytes might leave the destination
> string unterminated."
>
> Notice that, unlike strncpy(), strscpy() always null-terminates the
> destination string.
>
> Addresses-Coverity-ID: 1445537 ("Buffer not null terminated")
> Signed-off-by: Gustavo A. R. Silva <[email protected]>

Applied.

2019-05-29 07:03:38

by David Miller

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