From: Shuah Khan <shuah@kernel.org>
To: Jonathan Dieter <jdieter@lesbg.com>,
linux-kernel@vger.kernel.org,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Krzysztof Opasiak <k.opasiak@samsung.com>
Cc: Valentina Manea <valentina.manea.m@gmail.com>,
Peter Senna Tschudin <peter.senna@gmail.com>,
"open list:USB OVER IP DRIVER" <linux-usb@vger.kernel.org>
Subject: Re: [PATCH v4 1/2] usbip: Fix-format-overflow
Date: Thu, 16 Mar 2017 09:04:54 -0600 [thread overview]
Message-ID: <0dd8ccff-37c7-c7fd-0e33-84e6f69ff4d7@kernel.org> (raw)
In-Reply-To: <20170227083108.16391-1-jdieter@lesbg.com>
On 02/27/2017 01:31 AM, Jonathan Dieter wrote:
> The usbip userspace tools call sprintf()/snprintf() and don't check for
> the return value which can lead the paths to overflow, truncating the
> final file in the path.
>
> More urgently, GCC 7 now warns that these aren't checked with
> -Wformat-overflow, and with -Werror enabled in configure.ac, that makes
> these tools unbuildable.
>
> This patch fixes these problems by replacing sprintf() with snprintf() in
> one place and adding checks for the return value of snprintf().
>
> Reviewed-by: Peter Senna Tschudin <peter.senna@gmail.com>
> Signed-off-by: Jonathan Dieter <jdieter@lesbg.com>
Greg,
Please pick this up.
Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
thanks,
-- Shuah
> ---
> Changes since v3
> * Cast sizeof to long unsigned when printing errors to fix building for 32-bit
> architectures
>
> tools/usb/usbip/libsrc/usbip_common.c | 9 ++++++++-
> tools/usb/usbip/libsrc/usbip_host_common.c | 28 +++++++++++++++++++++++-----
> 2 files changed, 31 insertions(+), 6 deletions(-)
>
> diff --git a/tools/usb/usbip/libsrc/usbip_common.c b/tools/usb/usbip/libsrc/usbip_common.c
> index ac73710..1517a23 100644
> --- a/tools/usb/usbip/libsrc/usbip_common.c
> +++ b/tools/usb/usbip/libsrc/usbip_common.c
> @@ -215,9 +215,16 @@ int read_usb_interface(struct usbip_usb_device *udev, int i,
> struct usbip_usb_interface *uinf)
> {
> char busid[SYSFS_BUS_ID_SIZE];
> + int size;
> struct udev_device *sif;
>
> - sprintf(busid, "%s:%d.%d", udev->busid, udev->bConfigurationValue, i);
> + size = snprintf(busid, sizeof(busid), "%s:%d.%d",
> + udev->busid, udev->bConfigurationValue, i);
> + if (size < 0 || (unsigned int)size >= sizeof(busid)) {
> + err("busid length %i >= %lu or < 0", size,
> + (long unsigned)sizeof(busid));
> + return -1;
> + }
>
> sif = udev_device_new_from_subsystem_sysname(udev_context, "usb", busid);
> if (!sif) {
> diff --git a/tools/usb/usbip/libsrc/usbip_host_common.c b/tools/usb/usbip/libsrc/usbip_host_common.c
> index 9d41522..6ff7b60 100644
> --- a/tools/usb/usbip/libsrc/usbip_host_common.c
> +++ b/tools/usb/usbip/libsrc/usbip_host_common.c
> @@ -40,13 +40,20 @@ struct udev *udev_context;
> static int32_t read_attr_usbip_status(struct usbip_usb_device *udev)
> {
> char status_attr_path[SYSFS_PATH_MAX];
> + int size;
> int fd;
> int length;
> char status;
> int value = 0;
>
> - snprintf(status_attr_path, SYSFS_PATH_MAX, "%s/usbip_status",
> - udev->path);
> + size = snprintf(status_attr_path, sizeof(status_attr_path),
> + "%s/usbip_status", udev->path);
> + if (size < 0 || (unsigned int)size >= sizeof(status_attr_path)) {
> + err("usbip_status path length %i >= %lu or < 0", size,
> + (long unsigned)sizeof(status_attr_path));
> + return -1;
> + }
> +
>
> fd = open(status_attr_path, O_RDONLY);
> if (fd < 0) {
> @@ -218,6 +225,7 @@ int usbip_export_device(struct usbip_exported_device *edev, int sockfd)
> {
> char attr_name[] = "usbip_sockfd";
> char sockfd_attr_path[SYSFS_PATH_MAX];
> + int size;
> char sockfd_buff[30];
> int ret;
>
> @@ -237,10 +245,20 @@ int usbip_export_device(struct usbip_exported_device *edev, int sockfd)
> }
>
> /* only the first interface is true */
> - snprintf(sockfd_attr_path, sizeof(sockfd_attr_path), "%s/%s",
> - edev->udev.path, attr_name);
> + size = snprintf(sockfd_attr_path, sizeof(sockfd_attr_path), "%s/%s",
> + edev->udev.path, attr_name);
> + if (size < 0 || (unsigned int)size >= sizeof(sockfd_attr_path)) {
> + err("exported device path length %i >= %lu or < 0", size,
> + (long unsigned)sizeof(sockfd_attr_path));
> + return -1;
> + }
>
> - snprintf(sockfd_buff, sizeof(sockfd_buff), "%d\n", sockfd);
> + size = snprintf(sockfd_buff, sizeof(sockfd_buff), "%d\n", sockfd);
> + if (size < 0 || (unsigned int)size >= sizeof(sockfd_buff)) {
> + err("socket length %i >= %lu or < 0", size,
> + (long unsigned)sizeof(sockfd_buff));
> + return -1;
> + }
>
> ret = write_sysfs_attribute(sockfd_attr_path, sockfd_buff,
> strlen(sockfd_buff));
>
next prev parent reply other threads:[~2017-03-16 15:07 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20170220205937epcas3p4e334a658cf4d67f4a7d5a4ae7ce10afc@epcas3p4.samsung.com>
2017-02-20 20:51 ` [PATCH 1/2] Fix format overflows Jonathan Dieter
2017-02-20 20:51 ` [PATCH 2/2] Fix implicit fallthrough warning Jonathan Dieter
2017-02-21 6:12 ` [PATCH 1/2] Fix format overflows Krzysztof Opasiak
2017-02-21 6:48 ` Jonathan Dieter
2017-02-21 17:50 ` Jonathan Dieter
2017-02-21 17:57 ` [PATCH v2 1/2] usbip: Fix-format-overflow Jonathan Dieter
2017-02-21 17:57 ` [PATCH v2 2/2] usbip: Fix implicit fallthrough warning Jonathan Dieter
2017-02-22 5:49 ` [PATCH v2 1/2] usbip: Fix-format-overflow Krzysztof Opasiak
2017-02-22 18:14 ` Jonathan Dieter
2017-02-22 18:17 ` [PATCH v3 " Jonathan Dieter
2017-02-22 18:18 ` [PATCH v3 2/2] usbip: Fix implicit fallthrough warning Jonathan Dieter
2017-02-27 8:31 ` [PATCH v4 1/2] usbip: Fix-format-overflow Jonathan Dieter
2017-02-27 8:31 ` [PATCH v4 2/2] usbip: Fix implicit fallthrough warning Jonathan Dieter
2017-03-16 7:47 ` [PATCH v4 1/2] usbip: Fix-format-overflow Jonathan Dieter
2017-03-16 15:04 ` Shuah Khan [this message]
2017-03-17 1:37 ` Greg Kroah-Hartman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=0dd8ccff-37c7-c7fd-0e33-84e6f69ff4d7@kernel.org \
--to=shuah@kernel.org \
--cc=gregkh@linuxfoundation.org \
--cc=jdieter@lesbg.com \
--cc=k.opasiak@samsung.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=peter.senna@gmail.com \
--cc=valentina.manea.m@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).