* [PATCH v2] usbip: tools: fix GCC8 warning for strncpy
@ 2019-07-25 13:22 Liu, Changcheng
2019-07-25 14:19 ` shuah
0 siblings, 1 reply; 4+ messages in thread
From: Liu, Changcheng @ 2019-07-25 13:22 UTC (permalink / raw)
To: valentina.manea.m, shuah; +Cc: linux-usb
GCC8 started emitting warning about using strncpy with number of bytes
exactly equal destination size which could lead to non-zero terminated
string being copied. Use "SYSFS_PATH_MAX - 1" & "SYSFS_BUS_ID_SIZE - 1"
as number of bytes to ensure name is always zero-terminated.
Signed-off-by: Changcheng Liu <changcheng.liu@aliyun.com>
---
v1 -> v2:
* Correct array tail index
---
tools/usb/usbip/libsrc/usbip_common.c | 6 ++++--
tools/usb/usbip/libsrc/usbip_device_driver.c | 6 ++++--
2 files changed, 8 insertions(+), 4 deletions(-)
diff --git a/tools/usb/usbip/libsrc/usbip_common.c b/tools/usb/usbip/libsrc/usbip_common.c
index bb424638d75b..b8d7d480595a 100644
--- a/tools/usb/usbip/libsrc/usbip_common.c
+++ b/tools/usb/usbip/libsrc/usbip_common.c
@@ -226,8 +226,10 @@ int read_usb_device(struct udev_device *sdev, struct usbip_usb_device *udev)
path = udev_device_get_syspath(sdev);
name = udev_device_get_sysname(sdev);
- strncpy(udev->path, path, SYSFS_PATH_MAX);
- strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE);
+ strncpy(udev->path, path, SYSFS_PATH_MAX - 1);
+ udev->path[SYSFS_PATH_MAX - 1] = '\0';
+ strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE - 1);
+ udev->busid[SYSFS_BUS_ID_SIZE - 1] = '\0';
sscanf(name, "%u-%u", &busnum, &devnum);
udev->busnum = busnum;
diff --git a/tools/usb/usbip/libsrc/usbip_device_driver.c b/tools/usb/usbip/libsrc/usbip_device_driver.c
index 5a3726eb44ab..051d7d3f443b 100644
--- a/tools/usb/usbip/libsrc/usbip_device_driver.c
+++ b/tools/usb/usbip/libsrc/usbip_device_driver.c
@@ -91,7 +91,8 @@ int read_usb_vudc_device(struct udev_device *sdev, struct usbip_usb_device *dev)
copy_descr_attr16(dev, &descr, idProduct);
copy_descr_attr16(dev, &descr, bcdDevice);
- strncpy(dev->path, path, SYSFS_PATH_MAX);
+ strncpy(dev->path, path, SYSFS_PATH_MAX - 1);
+ dev->path[SYSFS_PATH_MAX - 1] = '\0';
dev->speed = USB_SPEED_UNKNOWN;
speed = udev_device_get_sysattr_value(sdev, "current_speed");
@@ -110,7 +111,8 @@ int read_usb_vudc_device(struct udev_device *sdev, struct usbip_usb_device *dev)
dev->busnum = 0;
name = udev_device_get_sysname(plat);
- strncpy(dev->busid, name, SYSFS_BUS_ID_SIZE);
+ strncpy(dev->busid, name, SYSFS_BUS_ID_SIZE - 1);
+ dev->busid[SYSFS_BUS_ID_SIZE - 1] = '\0';
return 0;
err:
fclose(fd);
--
2.17.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH v2] usbip: tools: fix GCC8 warning for strncpy
2019-07-25 13:22 [PATCH v2] usbip: tools: fix GCC8 warning for strncpy Liu, Changcheng
@ 2019-07-25 14:19 ` shuah
2019-07-25 14:44 ` Liu, Changcheng
0 siblings, 1 reply; 4+ messages in thread
From: shuah @ 2019-07-25 14:19 UTC (permalink / raw)
To: Liu, Changcheng, valentina.manea.m; +Cc: linux-usb, shuah
On 7/25/19 7:22 AM, Liu, Changcheng wrote:
> GCC8 started emitting warning about using strncpy with number of bytes
> exactly equal destination size which could lead to non-zero terminated
> string being copied. Use "SYSFS_PATH_MAX - 1" & "SYSFS_BUS_ID_SIZE - 1"
> as number of bytes to ensure name is always zero-terminated.
>
> Signed-off-by: Changcheng Liu <changcheng.liu@aliyun.com>
> ---
> v1 -> v2:
> * Correct array tail index
> ---
> tools/usb/usbip/libsrc/usbip_common.c | 6 ++++--
> tools/usb/usbip/libsrc/usbip_device_driver.c | 6 ++++--
> 2 files changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/tools/usb/usbip/libsrc/usbip_common.c b/tools/usb/usbip/libsrc/usbip_common.c
> index bb424638d75b..b8d7d480595a 100644
> --- a/tools/usb/usbip/libsrc/usbip_common.c
> +++ b/tools/usb/usbip/libsrc/usbip_common.c
> @@ -226,8 +226,10 @@ int read_usb_device(struct udev_device *sdev, struct usbip_usb_device *udev)
> path = udev_device_get_syspath(sdev);
> name = udev_device_get_sysname(sdev);
>
> - strncpy(udev->path, path, SYSFS_PATH_MAX);
> - strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE);
> + strncpy(udev->path, path, SYSFS_PATH_MAX - 1);
> + udev->path[SYSFS_PATH_MAX - 1] = '\0';
> + strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE - 1);
> + udev->busid[SYSFS_BUS_ID_SIZE - 1] = '\0';
strlcpy() would be better choice here. Any reason to not use that?
>
> sscanf(name, "%u-%u", &busnum, &devnum);
> udev->busnum = busnum;
> diff --git a/tools/usb/usbip/libsrc/usbip_device_driver.c b/tools/usb/usbip/libsrc/usbip_device_driver.c
> index 5a3726eb44ab..051d7d3f443b 100644
> --- a/tools/usb/usbip/libsrc/usbip_device_driver.c
> +++ b/tools/usb/usbip/libsrc/usbip_device_driver.c
> @@ -91,7 +91,8 @@ int read_usb_vudc_device(struct udev_device *sdev, struct usbip_usb_device *dev)
> copy_descr_attr16(dev, &descr, idProduct);
> copy_descr_attr16(dev, &descr, bcdDevice);
>
> - strncpy(dev->path, path, SYSFS_PATH_MAX);
> + strncpy(dev->path, path, SYSFS_PATH_MAX - 1);
> + dev->path[SYSFS_PATH_MAX - 1] = '\0';
>
> dev->speed = USB_SPEED_UNKNOWN;
> speed = udev_device_get_sysattr_value(sdev, "current_speed");
> @@ -110,7 +111,8 @@ int read_usb_vudc_device(struct udev_device *sdev, struct usbip_usb_device *dev)
> dev->busnum = 0;
>
> name = udev_device_get_sysname(plat);
> - strncpy(dev->busid, name, SYSFS_BUS_ID_SIZE);
> + strncpy(dev->busid, name, SYSFS_BUS_ID_SIZE - 1);
> + dev->busid[SYSFS_BUS_ID_SIZE - 1] = '\0';
strlcpy() would be better choice here. Any reason to not use that?
> return 0;
> err:
> fclose(fd);
>
thanks,
-- Shuah
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v2] usbip: tools: fix GCC8 warning for strncpy
2019-07-25 14:19 ` shuah
@ 2019-07-25 14:44 ` Liu, Changcheng
2019-07-25 16:06 ` shuah
0 siblings, 1 reply; 4+ messages in thread
From: Liu, Changcheng @ 2019-07-25 14:44 UTC (permalink / raw)
To: shuah; +Cc: valentina.manea.m, linux-usb
On 08:19 Thu 25 Jul, shuah wrote:
> On 7/25/19 7:22 AM, Liu, Changcheng wrote:
> > GCC8 started emitting warning about using strncpy with number of bytes
> > exactly equal destination size which could lead to non-zero terminated
> > string being copied. Use "SYSFS_PATH_MAX - 1" & "SYSFS_BUS_ID_SIZE - 1"
> > as number of bytes to ensure name is always zero-terminated.
> >
> > Signed-off-by: Changcheng Liu <changcheng.liu@aliyun.com>
> > ---
> > v1 -> v2:
> > * Correct array tail index
> > ---
> > tools/usb/usbip/libsrc/usbip_common.c | 6 ++++--
> > tools/usb/usbip/libsrc/usbip_device_driver.c | 6 ++++--
> > 2 files changed, 8 insertions(+), 4 deletions(-)
> >
> > diff --git a/tools/usb/usbip/libsrc/usbip_common.c b/tools/usb/usbip/libsrc/usbip_common.c
> > index bb424638d75b..b8d7d480595a 100644
> > --- a/tools/usb/usbip/libsrc/usbip_common.c
> > +++ b/tools/usb/usbip/libsrc/usbip_common.c
> > @@ -226,8 +226,10 @@ int read_usb_device(struct udev_device *sdev, struct usbip_usb_device *udev)
> > path = udev_device_get_syspath(sdev);
> > name = udev_device_get_sysname(sdev);
> > - strncpy(udev->path, path, SYSFS_PATH_MAX);
> > - strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE);
> > + strncpy(udev->path, path, SYSFS_PATH_MAX - 1);
> > + udev->path[SYSFS_PATH_MAX - 1] = '\0';
> > + strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE - 1);
> > + udev->busid[SYSFS_BUS_ID_SIZE - 1] = '\0';
>
> strlcpy() would be better choice here. Any reason to not use that?
>
@Shuah: linux tools link with libc which doesn't implment strlcpy yet.
So tools source code can't use strlcpy function like other kernel source
code.
> > sscanf(name, "%u-%u", &busnum, &devnum);
> > udev->busnum = busnum;
> > diff --git a/tools/usb/usbip/libsrc/usbip_device_driver.c b/tools/usb/usbip/libsrc/usbip_device_driver.c
> > index 5a3726eb44ab..051d7d3f443b 100644
> > --- a/tools/usb/usbip/libsrc/usbip_device_driver.c
> > +++ b/tools/usb/usbip/libsrc/usbip_device_driver.c
> > @@ -91,7 +91,8 @@ int read_usb_vudc_device(struct udev_device *sdev, struct usbip_usb_device *dev)
> > copy_descr_attr16(dev, &descr, idProduct);
> > copy_descr_attr16(dev, &descr, bcdDevice);
> > - strncpy(dev->path, path, SYSFS_PATH_MAX);
> > + strncpy(dev->path, path, SYSFS_PATH_MAX - 1);
> > + dev->path[SYSFS_PATH_MAX - 1] = '\0';
> > dev->speed = USB_SPEED_UNKNOWN;
> > speed = udev_device_get_sysattr_value(sdev, "current_speed");
> > @@ -110,7 +111,8 @@ int read_usb_vudc_device(struct udev_device *sdev, struct usbip_usb_device *dev)
> > dev->busnum = 0;
> > name = udev_device_get_sysname(plat);
> > - strncpy(dev->busid, name, SYSFS_BUS_ID_SIZE);
> > + strncpy(dev->busid, name, SYSFS_BUS_ID_SIZE - 1);
> > + dev->busid[SYSFS_BUS_ID_SIZE - 1] = '\0';
>
> strlcpy() would be better choice here. Any reason to not use that?
>
> > return 0;
> > err:
> > fclose(fd);
> >
>
> thanks,
> -- Shuah
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v2] usbip: tools: fix GCC8 warning for strncpy
2019-07-25 14:44 ` Liu, Changcheng
@ 2019-07-25 16:06 ` shuah
0 siblings, 0 replies; 4+ messages in thread
From: shuah @ 2019-07-25 16:06 UTC (permalink / raw)
To: Liu, Changcheng, Greg Kroah-Hartman; +Cc: valentina.manea.m, linux-usb
On 7/25/19 8:44 AM, Liu, Changcheng wrote:
> On 08:19 Thu 25 Jul, shuah wrote:
>> On 7/25/19 7:22 AM, Liu, Changcheng wrote:
>>> GCC8 started emitting warning about using strncpy with number of bytes
>>> exactly equal destination size which could lead to non-zero terminated
>>> string being copied. Use "SYSFS_PATH_MAX - 1" & "SYSFS_BUS_ID_SIZE - 1"
>>> as number of bytes to ensure name is always zero-terminated.
>>>
>>> Signed-off-by: Changcheng Liu <changcheng.liu@aliyun.com>
>>> ---
>>> v1 -> v2:
>>> * Correct array tail index
>>> ---
>>> tools/usb/usbip/libsrc/usbip_common.c | 6 ++++--
>>> tools/usb/usbip/libsrc/usbip_device_driver.c | 6 ++++--
>>> 2 files changed, 8 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/tools/usb/usbip/libsrc/usbip_common.c b/tools/usb/usbip/libsrc/usbip_common.c
>>> index bb424638d75b..b8d7d480595a 100644
>>> --- a/tools/usb/usbip/libsrc/usbip_common.c
>>> +++ b/tools/usb/usbip/libsrc/usbip_common.c
>>> @@ -226,8 +226,10 @@ int read_usb_device(struct udev_device *sdev, struct usbip_usb_device *udev)
>>> path = udev_device_get_syspath(sdev);
>>> name = udev_device_get_sysname(sdev);
>>> - strncpy(udev->path, path, SYSFS_PATH_MAX);
>>> - strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE);
>>> + strncpy(udev->path, path, SYSFS_PATH_MAX - 1);
>>> + udev->path[SYSFS_PATH_MAX - 1] = '\0';
>>> + strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE - 1);
>>> + udev->busid[SYSFS_BUS_ID_SIZE - 1] = '\0';
>>
>> strlcpy() would be better choice here. Any reason to not use that?
>>
> @Shuah: linux tools link with libc which doesn't implment strlcpy yet.
> So tools source code can't use strlcpy function like other kernel source
> code.
Right I keep forgetting that. :)
Thinking about it, udev_device_get_syspath() could return
null. Not related to this change anyway.
Thanks for fixing this.
Greg! Please pick this up:
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
thanks,
-- Shuah
^ permalink raw reply [flat|nested] 4+ messages in thread
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2019-07-25 13:22 [PATCH v2] usbip: tools: fix GCC8 warning for strncpy Liu, Changcheng
2019-07-25 14:19 ` shuah
2019-07-25 14:44 ` Liu, Changcheng
2019-07-25 16:06 ` shuah
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