[patch] hid2hci check usb_init return value

[patch] hid2hci check usb_init return value

[Khem Raj]

[-- Attachment #1: Type: text/plain, Size: 597 bytes --]

Hi

Working on a system which did not have a USB in it. I was getting a
segfault with hid2hci. The problem tracked down was usb_init () was 
failing and we did not check for it and carried on with execution. 
As a result the next call to libusb failed because we passed in NULL for
ctx because during usb_init () this should have been malloc'ed if all
have gone correctly but in case of error usb_init () free's up the
allocated memory and hence the segfault. 

We should check for return value of usb_init () call and exit
immediately if it fails. Tested on 4.24 release. 

OK ?

Thanks

-Khem



[-- Attachment #2: hid2hci_usb_init.patch --]
[-- Type: text/x-diff, Size: 1108 bytes --]

# Signed-off-by: Khem Raj <raj.khem@gmail.com>
#
# Use the new usb1 API for usb_init() and check for fails from 
# usb_init (). Currently we see a crash on a system which does
# not have USB because usb_init() fails and it cleans up all initialized
# data (e.g. ctx) which is used in subsequent calls to libusb
# We return immediately if usb_init() fails for some reason.

Index: bluez-4.24/tools/hid2hci.c
===================================================================
--- bluez-4.24.orig/tools/hid2hci.c	2008-10-25 23:40:34.000000000 -0700
+++ bluez-4.24/tools/hid2hci.c	2008-12-25 01:24:12.000000000 -0800
@@ -337,7 +337,7 @@
 int main(int argc, char *argv[])
 {
 	struct device_info dev[16];
-	int i, opt, num, quiet = 0, mode = HCI;
+	int i, ret, opt, num, quiet = 0, mode = HCI;
 
 	while ((opt = getopt_long(argc, argv, "+01qh", main_options, NULL)) != -1) {
 		switch (opt) {
@@ -361,8 +361,9 @@
 	argc -= optind;
 	argv += optind;
 	optind = 0;
-
-	usb_init();
+	ret = usb_init();
+	if (ret < 0)
+		return ret;
 
 	num = find_devices(mode, dev, sizeof(dev) / sizeof(dev[0]));
 	if (num <= 0) {

Re: [patch] hid2hci check usb_init return value

[Marcel Holtmann]

Hi Khem,

> Working on a system which did not have a USB in it. I was getting a
> segfault with hid2hci. The problem tracked down was usb_init () was 
> failing and we did not check for it and carried on with execution. 
> As a result the next call to libusb failed because we passed in NULL for
> ctx because during usb_init () this should have been malloc'ed if all
> have gone correctly but in case of error usb_init () free's up the
> allocated memory and hence the segfault. 
> 
> We should check for return value of usb_init () call and exit
> immediately if it fails. Tested on 4.24 release. 

the problem is that usb_init() doesn't return any errors on the versions
that I have here:

ii  libusb-0.1-4   2:0.1.12-12    userspace USB programming library
ii  libusb-dev     2:0.1.12-12    userspace USB programming library

Applying your patch would break complication on multiple platforms.

Regards

Marcel

Re: [patch] hid2hci check usb_init return value

[Khem Raj]

[-- Attachment #1: Type: text/plain, Size: 1382 bytes --]

On (29/12/08 13:12), Marcel Holtmann wrote:
> Hi Khem,
> 
> > Working on a system which did not have a USB in it. I was getting a
> > segfault with hid2hci. The problem tracked down was usb_init () was 
> > failing and we did not check for it and carried on with execution. 
> > As a result the next call to libusb failed because we passed in NULL for
> > ctx because during usb_init () this should have been malloc'ed if all
> > have gone correctly but in case of error usb_init () free's up the
> > allocated memory and hence the segfault. 
> > 
> > We should check for return value of usb_init () call and exit
> > immediately if it fails. Tested on 4.24 release. 
> 
> the problem is that usb_init() doesn't return any errors on the versions
> that I have here:
> 
> ii  libusb-0.1-4   2:0.1.12-12    userspace USB programming library
> ii  libusb-dev     2:0.1.12-12    userspace USB programming library
> 
> Applying your patch would break complication on multiple platforms.
What you have is libusb-0.1 which has older API I suppose. There is 
libusb-compat which can be used as a wrapper over libusb1 to give
libusb0 like interfaces. 

Actually I was using libusb-1.0.0 API as mentioned here
http://libusb.sourceforge.net/api-1.0/group__lib.html
that also means that the patch I attached should have been using
libusb_init() instead. 

Here is updated patch

Thanks

-Khem


[-- Attachment #2: hid2hci_usb_init.patch --]
[-- Type: text/x-diff, Size: 1111 bytes --]

# Signed-off-by: Khem Raj <raj.khem@gmail.com>
#
# Use the new usb1 API for usb_init() and check for fails from 
# usb_init (). Currently we see a crash on a system which does
# not have USB because usb_init() fails and it cleans up all initialized
# data (e.g. ctx) which is used in subsequent calls to libusb
# We return immediately if usb_init() fails for some reason.

Index: bluez-4.24/tools/hid2hci.c
===================================================================
--- bluez-4.24.orig/tools/hid2hci.c	2008-10-25 23:40:34.000000000 -0700
+++ bluez-4.24/tools/hid2hci.c	2008-12-29 22:06:04.000000000 -0800
@@ -337,7 +337,7 @@
 int main(int argc, char *argv[])
 {
 	struct device_info dev[16];
-	int i, opt, num, quiet = 0, mode = HCI;
+	int i, ret, opt, num, quiet = 0, mode = HCI;
 
 	while ((opt = getopt_long(argc, argv, "+01qh", main_options, NULL)) != -1) {
 		switch (opt) {
@@ -361,8 +361,9 @@
 	argc -= optind;
 	argv += optind;
 	optind = 0;
-
-	usb_init();
+	ret = libusb_init();
+	if (ret < 0)
+		return ret;
 
 	num = find_devices(mode, dev, sizeof(dev) / sizeof(dev[0]));
 	if (num <= 0) {

Re: [patch] hid2hci check usb_init return value

[Marcel Holtmann]

Hi Khem,

> > > Working on a system which did not have a USB in it. I was getting a
> > > segfault with hid2hci. The problem tracked down was usb_init () was 
> > > failing and we did not check for it and carried on with execution. 
> > > As a result the next call to libusb failed because we passed in NULL for
> > > ctx because during usb_init () this should have been malloc'ed if all
> > > have gone correctly but in case of error usb_init () free's up the
> > > allocated memory and hence the segfault. 
> > > 
> > > We should check for return value of usb_init () call and exit
> > > immediately if it fails. Tested on 4.24 release. 
> > 
> > the problem is that usb_init() doesn't return any errors on the versions
> > that I have here:
> > 
> > ii  libusb-0.1-4   2:0.1.12-12    userspace USB programming library
> > ii  libusb-dev     2:0.1.12-12    userspace USB programming library
> > 
> > Applying your patch would break complication on multiple platforms.
> What you have is libusb-0.1 which has older API I suppose. There is 
> libusb-compat which can be used as a wrapper over libusb1 to give
> libusb0 like interfaces. 
> 
> Actually I was using libusb-1.0.0 API as mentioned here
> http://libusb.sourceforge.net/api-1.0/group__lib.html
> that also means that the patch I attached should have been using
> libusb_init() instead. 
> 
> Here is updated patch

this still breaks with a system that has libusb-0.1 installed like the
current Ubuntu 8.10 does. So either we switch to libusb-1.0 completely
or we leave it as it is.

Regards

Marcel

Re: [patch] hid2hci check usb_init return value

[David Sainty]

Marcel Holtmann wrote:
>> What you have is libusb-0.1 which has older API I suppose. There is 
>> libusb-compat which can be used as a wrapper over libusb1 to give
>> libusb0 like interfaces. 
>>
>> Actually I was using libusb-1.0.0 API as mentioned here
>> http://libusb.sourceforge.net/api-1.0/group__lib.html
>> that also means that the patch I attached should have been using
>> libusb_init() instead. 
>>
>> Here is updated patch
>>     
>
> this still breaks with a system that has libusb-0.1 installed like the
> current Ubuntu 8.10 does. So either we switch to libusb-1.0 completely
> or we leave it as it is.
>   

This looks like a job for autoconf?

Re: [patch] hid2hci check usb_init return value

[Marcel Holtmann]

Hi David,

> >> What you have is libusb-0.1 which has older API I suppose. There is 
> >> libusb-compat which can be used as a wrapper over libusb1 to give
> >> libusb0 like interfaces. 
> >>
> >> Actually I was using libusb-1.0.0 API as mentioned here
> >> http://libusb.sourceforge.net/api-1.0/group__lib.html
> >> that also means that the patch I attached should have been using
> >> libusb_init() instead. 
> >>
> >> Here is updated patch
> >>     
> >
> > this still breaks with a system that has libusb-0.1 installed like the
> > current Ubuntu 8.10 does. So either we switch to libusb-1.0 completely
> > or we leave it as it is.
> >   
> 
> This looks like a job for autoconf?

it could be, but I am only doing either libusb-0.1 or libusb-1.0. We can
have support for both, but these compile time options are a bad thing
and I don't want them.

Regards

Marcel

Re: [patch] hid2hci check usb_init return value

[Khem Raj]

On (06/01/09 03:54), Marcel Holtmann wrote:
> Hi Khem,
> 
> > > > Working on a system which did not have a USB in it. I was getting a
> > > > segfault with hid2hci. The problem tracked down was usb_init () was 
> > > > failing and we did not check for it and carried on with execution. 
> > > > As a result the next call to libusb failed because we passed in NULL for
> > > > ctx because during usb_init () this should have been malloc'ed if all
> > > > have gone correctly but in case of error usb_init () free's up the
> > > > allocated memory and hence the segfault. 
> > > > 
> > > > We should check for return value of usb_init () call and exit
> > > > immediately if it fails. Tested on 4.24 release. 
> > > 
> > > the problem is that usb_init() doesn't return any errors on the versions
> > > that I have here:
> > > 
> > > ii  libusb-0.1-4   2:0.1.12-12    userspace USB programming library
> > > ii  libusb-dev     2:0.1.12-12    userspace USB programming library
> > > 
> > > Applying your patch would break complication on multiple platforms.
> > What you have is libusb-0.1 which has older API I suppose. There is 
> > libusb-compat which can be used as a wrapper over libusb1 to give
> > libusb0 like interfaces. 
> > 
> > Actually I was using libusb-1.0.0 API as mentioned here
> > http://libusb.sourceforge.net/api-1.0/group__lib.html
> > that also means that the patch I attached should have been using
> > libusb_init() instead. 
> > 
> > Here is updated patch
> 
> this still breaks with a system that has libusb-0.1 installed like the
> current Ubuntu 8.10 does. So either we switch to libusb-1.0 completely
> or we leave it as it is.

Moving forward depending on libusb-1.0 seems a better idea to me. 

Thanks

-Khem

Re: [patch] hid2hci check usb_init return value

[Marcel Holtmann]

Hi Khem,

> > > > > Working on a system which did not have a USB in it. I was getting a
> > > > > segfault with hid2hci. The problem tracked down was usb_init () was 
> > > > > failing and we did not check for it and carried on with execution. 
> > > > > As a result the next call to libusb failed because we passed in NULL for
> > > > > ctx because during usb_init () this should have been malloc'ed if all
> > > > > have gone correctly but in case of error usb_init () free's up the
> > > > > allocated memory and hence the segfault. 
> > > > > 
> > > > > We should check for return value of usb_init () call and exit
> > > > > immediately if it fails. Tested on 4.24 release. 
> > > > 
> > > > the problem is that usb_init() doesn't return any errors on the versions
> > > > that I have here:
> > > > 
> > > > ii  libusb-0.1-4   2:0.1.12-12    userspace USB programming library
> > > > ii  libusb-dev     2:0.1.12-12    userspace USB programming library
> > > > 
> > > > Applying your patch would break complication on multiple platforms.
> > > What you have is libusb-0.1 which has older API I suppose. There is 
> > > libusb-compat which can be used as a wrapper over libusb1 to give
> > > libusb0 like interfaces. 
> > > 
> > > Actually I was using libusb-1.0.0 API as mentioned here
> > > http://libusb.sourceforge.net/api-1.0/group__lib.html
> > > that also means that the patch I attached should have been using
> > > libusb_init() instead. 
> > > 
> > > Here is updated patch
> > 
> > this still breaks with a system that has libusb-0.1 installed like the
> > current Ubuntu 8.10 does. So either we switch to libusb-1.0 completely
> > or we leave it as it is.
> 
> Moving forward depending on libusb-1.0 seems a better idea to me. 

feel free to submit patches for all utilities with USB support. Then we
can talk about switching.

Regards

Marcel